diff --git a/cli/src/main/java/hudson/util/QuotedStringTokenizer.java b/cli/src/main/java/hudson/util/QuotedStringTokenizer.java
index 017016d7d8..b81de9194d 100644
--- a/cli/src/main/java/hudson/util/QuotedStringTokenizer.java
+++ b/cli/src/main/java/hudson/util/QuotedStringTokenizer.java
@@ -472,7 +472,7 @@ public class QuotedStringTokenizer
                                 (convertHexDigit((byte)s.charAt(i++))<<24)+
                                 (convertHexDigit((byte)s.charAt(i++))<<16)+
                                 (convertHexDigit((byte)s.charAt(i++))<<8)+
-                                (convertHexDigit((byte)s.charAt(i++)))
+                                convertHexDigit((byte)s.charAt(i++))
                                 )
                         );
                         break;
diff --git a/core/src/main/java/hudson/ExtensionList.java b/core/src/main/java/hudson/ExtensionList.java
index 9855ec9e1e..05eeaa872d 100644
--- a/core/src/main/java/hudson/ExtensionList.java
+++ b/core/src/main/java/hudson/ExtensionList.java
@@ -246,7 +246,7 @@ public class ExtensionList<T> extends AbstractList<T> implements OnMaster {
         return removed;
     }
 
-    private <T> boolean removeComponent(Collection<ExtensionComponent<T>> collection, Object t) {
+    private boolean removeComponent(Collection<ExtensionComponent<T>> collection, Object t) {
         for (ExtensionComponent<T> c : collection) {
             if (c.getInstance().equals(t)) {
                 return collection.remove(c);
diff --git a/core/src/main/java/hudson/ExtensionListView.java b/core/src/main/java/hudson/ExtensionListView.java
index 53a577522a..c361c1a620 100644
--- a/core/src/main/java/hudson/ExtensionListView.java
+++ b/core/src/main/java/hudson/ExtensionListView.java
@@ -144,7 +144,7 @@ public class ExtensionListView {
             }
 
             @Override
-            public <T> T[] toArray(T[] array) {
+            public <X> X[] toArray(X[] array) {
                 return storage().toArray(array);
             }
 
diff --git a/core/src/main/java/hudson/FilePath.java b/core/src/main/java/hudson/FilePath.java
index ff868a31c5..f4ded0b0cd 100644
--- a/core/src/main/java/hudson/FilePath.java
+++ b/core/src/main/java/hudson/FilePath.java
@@ -2023,6 +2023,7 @@ public final class FilePath implements SerializableOnlyOverRemoting {
      * List up files in this directory that matches the given Ant-style filter.
      *
      * @param includes
+     *      See {@link FileSet} for the syntax. String like "foo/*.zip" or "foo/*&#42;/*.xml"
      * @param excludes
      *      See {@link FileSet} for the syntax. String like "foo/*.zip" or "foo/*&#42;/*.xml"
      * @return
@@ -2038,6 +2039,7 @@ public final class FilePath implements SerializableOnlyOverRemoting {
      * List up files in this directory that matches the given Ant-style filter.
      *
      * @param includes
+     *      See {@link FileSet} for the syntax. String like "foo/*.zip" or "foo/*&#42;/*.xml"
      * @param excludes
      *      See {@link FileSet} for the syntax. String like "foo/*.zip" or "foo/*&#42;/*.xml"
      * @param defaultExcludes whether to use the ant default excludes
diff --git a/core/src/main/java/hudson/Functions.java b/core/src/main/java/hudson/Functions.java
index 96200deb4f..6756715726 100644
--- a/core/src/main/java/hudson/Functions.java
+++ b/core/src/main/java/hudson/Functions.java
@@ -236,8 +236,6 @@ public class Functions {
 
     /**
      * Returns a localized string for the specified date, not including time.
-     * @param date
-     * @return
      */
     @Restricted(NoExternalUse.class)
     public static String localDate(Date date) {
@@ -250,9 +248,6 @@ public class Functions {
 
     /**
      * Returns a human-readable string describing the time difference between now and the specified date.
-     *
-     * @param date
-     * @return
      */
     @Restricted(NoExternalUse.class)
     public static String getTimeSpanString(Date date) {
diff --git a/core/src/main/java/hudson/PluginStrategy.java b/core/src/main/java/hudson/PluginStrategy.java
index 0a4a6e7968..9645d9c780 100644
--- a/core/src/main/java/hudson/PluginStrategy.java
+++ b/core/src/main/java/hudson/PluginStrategy.java
@@ -70,8 +70,6 @@ public interface PluginStrategy extends ExtensionPoint {
 	/**
 	 * Optionally start services provided by the plugin. Should be called
 	 * when all plugins are loaded.
-	 * 
-	 * @param plugin
 	 */
 	void initializeComponents(PluginWrapper plugin);
 
diff --git a/core/src/main/java/hudson/PluginWrapper.java b/core/src/main/java/hudson/PluginWrapper.java
index 8afe949c97..0fee6b1ea2 100644
--- a/core/src/main/java/hudson/PluginWrapper.java
+++ b/core/src/main/java/hudson/PluginWrapper.java
@@ -721,7 +721,6 @@ public class PluginWrapper implements Comparable<PluginWrapper>, ModelObject {
 
     /**
      * Disable a plugin wihout checking any dependency. Only add the disable file.
-     * @throws IOException
      */
     private void disableWithoutCheck() throws IOException {
         try (OutputStream os = Files.newOutputStream(disableFile.toPath())) {
diff --git a/core/src/main/java/hudson/ProxyConfiguration.java b/core/src/main/java/hudson/ProxyConfiguration.java
index d04fad9ecb..3a48c857da 100644
--- a/core/src/main/java/hudson/ProxyConfiguration.java
+++ b/core/src/main/java/hudson/ProxyConfiguration.java
@@ -344,7 +344,6 @@ public final class ProxyConfiguration extends AbstractDescribableImpl<ProxyConfi
     /**
      * If the first URL we try to access with a HTTP proxy is HTTPS then the authentication cache will not have been
      * pre-populated, so we try to access at least one HTTP URL before the very first HTTPS url.
-     * @param proxy
      * @param url the actual URL being opened.
      */
     private void jenkins48775workaround(Proxy proxy, URL url) {
diff --git a/core/src/main/java/hudson/cli/CliTransportAuthenticator.java b/core/src/main/java/hudson/cli/CliTransportAuthenticator.java
index 1271074a71..3e865c15ad 100644
--- a/core/src/main/java/hudson/cli/CliTransportAuthenticator.java
+++ b/core/src/main/java/hudson/cli/CliTransportAuthenticator.java
@@ -30,7 +30,6 @@ public abstract class CliTransportAuthenticator implements ExtensionPoint {
      *      Protocol identifier that {@link #supportsProtocol(String)} returned true.
      * @param channel
      *      Communication channel to the client.
-     * @param con
      */
     public abstract void authenticate(String protocol, Channel channel, Connection con);
 
diff --git a/core/src/main/java/hudson/cli/declarative/MethodBinder.java b/core/src/main/java/hudson/cli/declarative/MethodBinder.java
index 069193c2f5..c63a50367a 100644
--- a/core/src/main/java/hudson/cli/declarative/MethodBinder.java
+++ b/core/src/main/java/hudson/cli/declarative/MethodBinder.java
@@ -52,9 +52,6 @@ class MethodBinder {
     private final Method method;
     private final Object[] arguments;
 
-    /**
-     * @param method
-     */
     MethodBinder(Method method, CLICommand command, CmdLineParser parser) {
         this.method = method;
         this.command = command;
diff --git a/core/src/main/java/hudson/model/AbstractItem.java b/core/src/main/java/hudson/model/AbstractItem.java
index b6153b4ced..c98604e41a 100644
--- a/core/src/main/java/hudson/model/AbstractItem.java
+++ b/core/src/main/java/hudson/model/AbstractItem.java
@@ -187,8 +187,6 @@ public abstract class AbstractItem extends Actionable implements Item, HttpDelet
      * This method exists so that the Job configuration pages can use 
      * getDisplayNameOrNull so that nothing is shown in the display name text
      * box if the display name is not set.
-     * @param displayName
-     * @throws IOException
      */
     public void setDisplayNameOrNull(String displayName) throws IOException {
         setDisplayName(displayName);
diff --git a/core/src/main/java/hudson/model/AbstractProject.java b/core/src/main/java/hudson/model/AbstractProject.java
index ba49050a04..ee6b22f6bf 100644
--- a/core/src/main/java/hudson/model/AbstractProject.java
+++ b/core/src/main/java/hudson/model/AbstractProject.java
@@ -1834,7 +1834,7 @@ public abstract class AbstractProject<P extends AbstractProject<P,R>,R extends A
     public DirectoryBrowserSupport doWs( StaplerRequest req, StaplerResponse rsp ) throws IOException, ServletException, InterruptedException {
         checkPermission(Item.WORKSPACE);
         FilePath ws = getSomeWorkspace();
-        if ((ws == null) || (!ws.exists())) {
+        if ((ws == null) || !ws.exists()) {
             // if there's no workspace, report a nice error message
             // Would be good if when asked for *plain*, do something else!
             // (E.g. return 404, or send empty doc.)
diff --git a/core/src/main/java/hudson/model/Actionable.java b/core/src/main/java/hudson/model/Actionable.java
index a986a5ab21..dbe8a80c40 100644
--- a/core/src/main/java/hudson/model/Actionable.java
+++ b/core/src/main/java/hudson/model/Actionable.java
@@ -319,7 +319,6 @@ public abstract class Actionable extends AbstractModelObject implements ModelObj
     /**
      * Gets the action (first instance to be found) of a specified type that contributed to this build.
      *
-     * @param type
      * @return The action or {@code null} if no such actions exist.
      * @see #getActions(Class)
      */
diff --git a/core/src/main/java/hudson/model/Computer.java b/core/src/main/java/hudson/model/Computer.java
index 0fa8f91a76..817c3460be 100644
--- a/core/src/main/java/hudson/model/Computer.java
+++ b/core/src/main/java/hudson/model/Computer.java
@@ -1506,7 +1506,7 @@ public /*transient*/ abstract class Computer extends Actionable implements Acces
             throw new ServletException("No such node " + nodeName);
         }
 
-        if ((!proposedName.equals(nodeName))
+        if (!proposedName.equals(nodeName)
                 && Jenkins.get().getNode(proposedName) != null) {
             throw new FormException(Messages.ComputerSet_SlaveAlreadyExists(proposedName), "name");
         }
diff --git a/core/src/main/java/hudson/model/Descriptor.java b/core/src/main/java/hudson/model/Descriptor.java
index c699bff536..8ccbf90a52 100644
--- a/core/src/main/java/hudson/model/Descriptor.java
+++ b/core/src/main/java/hudson/model/Descriptor.java
@@ -625,7 +625,7 @@ public abstract class Descriptor<T extends Describable<T>> implements Saveable,
     private static class NewInstanceBindInterceptor extends BindInterceptor {
 
         private final BindInterceptor oldInterceptor;
-        private final Map<JSONObject,Boolean> processed = new IdentityHashMap<>();
+        private final IdentityHashMap<JSONObject,Boolean> processed = new IdentityHashMap<>();
 
         NewInstanceBindInterceptor(BindInterceptor oldInterceptor) {
             LOGGER.log(Level.FINER, "new interceptor delegating to {0}", oldInterceptor);
diff --git a/core/src/main/java/hudson/model/FileParameterValue.java b/core/src/main/java/hudson/model/FileParameterValue.java
index 35d7a21639..562116328c 100644
--- a/core/src/main/java/hudson/model/FileParameterValue.java
+++ b/core/src/main/java/hudson/model/FileParameterValue.java
@@ -229,9 +229,6 @@ public class FileParameterValue extends ParameterValue {
 
     /**
      * Serve this file parameter in response to a {@link StaplerRequest}.
-     *
-     * @param request
-     * @param response
      */
     public DirectoryBrowserSupport doDynamic(StaplerRequest request, StaplerResponse response) {
         AbstractBuild build = (AbstractBuild)request.findAncestor(AbstractBuild.class).getObject();
diff --git a/core/src/main/java/hudson/model/Fingerprint.java b/core/src/main/java/hudson/model/Fingerprint.java
index 1a58caf458..a4809e5260 100644
--- a/core/src/main/java/hudson/model/Fingerprint.java
+++ b/core/src/main/java/hudson/model/Fingerprint.java
@@ -824,7 +824,7 @@ public class Fingerprint implements ModelObject, Saveable {
                               <end>1479</end>
                             </range>
                      */
-                    return new RangeSet((List<Range>)(collectionConv.unmarshal(reader,context)));
+                    return new RangeSet((List<Range>)collectionConv.unmarshal(reader,context));
                 } else {
                     return RangeSet.fromString(reader.getValue(),true);
                 }
diff --git a/core/src/main/java/hudson/model/ListView.java b/core/src/main/java/hudson/model/ListView.java
index 53ab1e44df..8d95f93dde 100644
--- a/core/src/main/java/hudson/model/ListView.java
+++ b/core/src/main/java/hudson/model/ListView.java
@@ -494,7 +494,6 @@ public class ListView extends View implements DirectlyModifiableView {
 
     /**
      * Deprecated see, {@link StatusFilter}
-     * @param statusFilter
      */
     @Deprecated
     @DataBoundSetter
diff --git a/core/src/main/java/hudson/model/Node.java b/core/src/main/java/hudson/model/Node.java
index 15d8099d24..47c44af19b 100644
--- a/core/src/main/java/hudson/model/Node.java
+++ b/core/src/main/java/hudson/model/Node.java
@@ -309,7 +309,6 @@ public abstract class Node extends AbstractModelObject implements Reconfigurable
      * Return all the labels assigned dynamically to this node.
      * This calls all the LabelFinder implementations with the node converts
      * the results into Labels.
-     * @return HashSet<Label>.
      */
     private HashSet<LabelAtom> getDynamicLabels() {
         HashSet<LabelAtom> result = new HashSet<>();
diff --git a/core/src/main/java/hudson/model/Queue.java b/core/src/main/java/hudson/model/Queue.java
index 8a19fef722..d6f9dbc9c1 100644
--- a/core/src/main/java/hudson/model/Queue.java
+++ b/core/src/main/java/hudson/model/Queue.java
@@ -611,7 +611,7 @@ public class Queue extends ResourceController implements Saveable {
                     shouldScheduleItem |= action.shouldSchedule(actions);
                 }
                 for (QueueAction action : Util.filter(actions, QueueAction.class)) {
-                    shouldScheduleItem |= action.shouldSchedule((new ArrayList<>(item.getAllActions())));
+                    shouldScheduleItem |= action.shouldSchedule(new ArrayList<>(item.getAllActions()));
                 }
                 if (!shouldScheduleItem) {
                     duplicatesInQueue.add(item);
@@ -2098,7 +2098,6 @@ public class Queue extends ResourceController implements Saveable {
          * Unique ID (per master) that tracks the {@link Task} as it moves through different stages
          * in the queue (each represented by different subtypes of {@link Item} and into any subsequent
          * {@link Run} instance (see {@link Run#getQueueId()}).
-         * @return
          * @since 1.601
          */
         @Exported
diff --git a/core/src/main/java/hudson/model/Run.java b/core/src/main/java/hudson/model/Run.java
index 9f91362e72..e569f7cfc7 100644
--- a/core/src/main/java/hudson/model/Run.java
+++ b/core/src/main/java/hudson/model/Run.java
@@ -1507,7 +1507,6 @@ public abstract class Run <JobT extends Job<JobT,RunT>,RunT extends Run<JobT,Run
      * Returns an input stream that reads from the log file.
      * It will use a gzip-compressed log file (log.gz) if that exists.
      *
-     * @throws IOException 
      * @return An input stream from the log file. 
      *   If the log file does not exist, the error message will be returned to the output.
      * @since 1.349
diff --git a/core/src/main/java/hudson/model/TransientViewActionFactory.java b/core/src/main/java/hudson/model/TransientViewActionFactory.java
index d5fa9dcfc2..87c96b9ac0 100644
--- a/core/src/main/java/hudson/model/TransientViewActionFactory.java
+++ b/core/src/main/java/hudson/model/TransientViewActionFactory.java
@@ -15,8 +15,6 @@ public abstract class TransientViewActionFactory implements ExtensionPoint {
 
 	/**
 	 * returns a list of (transient) actions never null, may be empty
-	 * 
-	 * @param v
 	 */
 	public abstract List<Action> createFor(View v);
 	
diff --git a/core/src/main/java/hudson/model/UpdateCenter.java b/core/src/main/java/hudson/model/UpdateCenter.java
index ff06c627c5..767d5bb512 100644
--- a/core/src/main/java/hudson/model/UpdateCenter.java
+++ b/core/src/main/java/hudson/model/UpdateCenter.java
@@ -1001,7 +1001,6 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
     /**
      * Returns a list of plugins that should be shown in the "available" tab, grouped by category.
      * A plugin with multiple categories will appear multiple times in the list.
-     * @deprecated
      */
     @Deprecated
     public PluginEntry[] getCategorizedAvailables() {
@@ -1092,10 +1091,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
      * browse to the instance.
      *
      * @return a list of {@link FormValidation} for each updated Update Site
-     * @throws ExecutionException
-     * @throws InterruptedException
      * @since 1.501
-     *
      */
     public List<FormValidation> updateAllSites() throws InterruptedException, ExecutionException {
         List <Future<FormValidation>> futures = new ArrayList<>();
@@ -1519,7 +1515,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
          * Immutable state of this job.
          */
          @Exported(inline=true)
-        public volatile RestartJenkinsJobStatus status = new Pending();
+        public volatile RestartJenkinsJobStatus status = new RestartJenkinsJob.Pending();
 
         /**
          * The name of the user that started this job
@@ -1530,8 +1526,8 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
          * Cancel job
          */
         public synchronized boolean cancel() {
-            if (status instanceof Pending) {
-                status = new Canceled();
+            if (status instanceof RestartJenkinsJob.Pending) {
+                status = new RestartJenkinsJob.Canceled();
                 return true;
             }
             return false;
@@ -1544,10 +1540,10 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
 
         @Override
         public synchronized void run() {
-            if (!(status instanceof Pending)) {
+            if (!(status instanceof RestartJenkinsJob.Pending)) {
                 return;
             }
-            status = new Running();
+            status = new RestartJenkinsJob.Running();
             try {
                 // safeRestart records the current authentication for the log, so set it to the managing user
                 try (ACLContext acl = ACL.as(User.get(authentication, false, Collections.emptyMap()))) {
@@ -1555,7 +1551,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 }
             } catch (RestartNotSupportedException exception) {
                 // ignore if restart is not allowed
-                status = new Failure();
+                status = new RestartJenkinsJob.Failure();
                 error = exception;
             }
         }
@@ -1702,7 +1698,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                         } catch (IOException e) {
                             LOGGER.log(Level.SEVERE, "Failed to enable " + plugin.getDisplayName(), e);
                             error = e;
-                            status = new Failure(e);
+                            status = new DownloadJob.Failure(e);
                         }
                         
                         if (dynamicLoad) {
@@ -1713,7 +1709,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                                 LOGGER.log(Level.SEVERE, "Failed to dynamically load " + plugin.getDisplayName(), e);
                                 error = e;
                                 requiresRestart = true;
-                                status = new Failure(e);
+                                status = new DownloadJob.Failure(e);
                             }
                         } else {
                             requiresRestart = true;
@@ -1724,10 +1720,10 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 LOGGER.log(Level.SEVERE, "An unexpected error occurred while attempting to enable " + plugin.getDisplayName(), e);
                 error = e;
                 requiresRestart = true;
-                status = new Failure(e);
+                status = new DownloadJob.Failure(e);
             }
-            if(status instanceof Pending) {
-                status = new Success();
+            if(status instanceof DownloadJob.Pending) {
+                status = new DownloadJob.Success();
             }
         }
     }
@@ -1742,7 +1738,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
         @Override
         public void run() {
             // do nothing
-            status = new Success();
+            status = new DownloadJob.Success();
         }
     }
 
@@ -1761,7 +1757,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
          * Immutable object representing the current state of this job.
          */
         @Exported(inline=true)
-        public volatile InstallationStatus status = new Pending();
+        public volatile InstallationStatus status = new DownloadJob.Pending();
 
         /**
          * Where to download the file from.
@@ -1854,7 +1850,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 _run();
 
                 LOGGER.info("Installation successful: "+getName());
-                status = new Success();
+                status = new DownloadJob.Success();
                 onSuccess();
             } catch (InstallationStatus e) {
                 status = e;
@@ -1862,11 +1858,11 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 requiresRestart |= status.requiresRestart();
             } catch (MissingDependencyException e) {
                 LOGGER.log(Level.SEVERE, "Failed to install {0}: {1}", new Object[] { getName(), e.getMessage() });
-                status = new Failure(e);
+                status = new DownloadJob.Failure(e);
                 error = e;
             } catch (Throwable e) {
                 LOGGER.log(Level.SEVERE, "Failed to install "+getName(),e);
-                status = new Failure(e);
+                status = new DownloadJob.Failure(e);
                 error = e;
             }
         }
@@ -2186,12 +2182,12 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                     try {
                         pm.dynamicLoad(getDestination(), false, batch);
                     } catch (RestartRequiredException e) {
-                        throw new SuccessButRequiresRestart(e.message);
+                        throw new DownloadJob.SuccessButRequiresRestart(e.message);
                     } catch (Exception e) {
                         throw new IOException("Failed to dynamically deploy this plugin",e);
                     }
                 } else {
-                    throw new SuccessButRequiresRestart(Messages._UpdateCenter_DownloadButNotActivated());
+                    throw new DownloadJob.SuccessButRequiresRestart(Messages._UpdateCenter_DownloadButNotActivated());
                 }
             } finally {
                 synchronized(this) {
@@ -2199,7 +2195,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                     LOGGER.fine("Install complete for: " + plugin.getDisplayName() + "@" + plugin.version);
                     // some status other than Installing or Downloading needs to be set here
                     // {@link #isAlreadyInstalling()}, it will be overwritten by {@link DownloadJob#run()}
-                    status = new Skipped();
+                    status = new DownloadJob.Skipped();
                     notifyAll();
                 }
             }
@@ -2222,7 +2218,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                         if (ij.plugin.equals(plugin) && ij.plugin.version.equals(plugin.version)) {
                             // wait until other install is completed
                             synchronized(ij) {
-                                if(ij.status instanceof Installing || ij.status instanceof Pending) {
+                                if(ij.status instanceof DownloadJob.Installing || ij.status instanceof DownloadJob.Pending) {
                                     try {
                                         LOGGER.fine("Waiting for other plugin install of: " + plugin.getDisplayName() + "@" + plugin.version);
                                         ij.wait();
@@ -2231,7 +2227,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                                     }
                                 }
                                 // Must check for success, otherwise may have failed installation
-                                if (ij.status instanceof Success) {
+                                if (ij.status instanceof DownloadJob.Success) {
                                     return true;
                                 }
                             }
@@ -2294,7 +2290,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
         private final List<PluginWrapper> batch;
         private final long start;
         @Exported(inline = true)
-        public volatile CompleteBatchJobStatus status = new Pending();
+        public volatile CompleteBatchJobStatus status = new CompleteBatchJob.Pending();
 
         public CompleteBatchJob(List<PluginWrapper> batch, long start, UUID correlationId) {
             super(getCoreSource());
@@ -2306,12 +2302,12 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
         @Override
         public void run() {
             LOGGER.info("Completing installing of plugin batch…");
-            status = new Running();
+            status = new CompleteBatchJob.Running();
             try {
                 Jenkins.get().getPluginManager().start(batch);
-                status = new Success();
+                status = new CompleteBatchJob.Success();
             } catch (Exception x) {
-                status = new Failure(x);
+                status = new CompleteBatchJob.Failure(x);
                 LOGGER.log(Level.WARNING, "Failed to start some plugins", x);
             }
             LOGGER.log(INFO, "Completed installation of {0} plugins in {1}", new Object[] {batch.size(), Util.getTimeSpanString((System.nanoTime() - start) / 1_000_000)});
@@ -2405,7 +2401,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 onSuccess();
             } catch (Throwable e) {
                 LOGGER.log(Level.SEVERE, "Failed to downgrade "+getName(),e);
-                status = new Failure(e);
+                status = new DownloadJob.Failure(e);
                 error = e;
             }
         }
@@ -2478,7 +2474,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
 
         @Override
         protected void onSuccess() {
-            status = new Success();
+            status = new DownloadJob.Success();
         }
 
         @Override
@@ -2524,7 +2520,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
         }
         @Override
         protected void onSuccess() {
-            status = new Success();
+            status = new DownloadJob.Success();
         }
         @Override
         public void run() {
@@ -2534,11 +2530,11 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
                 _run();
 
                 LOGGER.info("Downgrading successful: "+getName());
-                status = new Success();
+                status = new DownloadJob.Success();
                 onSuccess();
             } catch (Throwable e) {
                 LOGGER.log(Level.SEVERE, "Failed to downgrade "+getName(),e);
-                status = new Failure(e);
+                status = new DownloadJob.Failure(e);
                 error = e;
             }
         }
diff --git a/core/src/main/java/hudson/model/UpdateSite.java b/core/src/main/java/hudson/model/UpdateSite.java
index 36667b82a6..dd3e434a31 100644
--- a/core/src/main/java/hudson/model/UpdateSite.java
+++ b/core/src/main/java/hudson/model/UpdateSite.java
@@ -1169,8 +1169,8 @@ public class UpdateSite {
             this.releaseTimestamp = date;
             this.categories = o.has("labels") ? internInPlace((String[])o.getJSONArray("labels").toArray(EMPTY_STRING_ARRAY)) : null;
             JSONArray ja = o.getJSONArray("dependencies");
-            int depCount = (int)(ja.stream().filter(IS_DEP_PREDICATE.and(IS_NOT_OPTIONAL)).count());
-            int optionalDepCount = (int)(ja.stream().filter(IS_DEP_PREDICATE.and(IS_NOT_OPTIONAL.negate())).count());
+            int depCount = (int)ja.stream().filter(IS_DEP_PREDICATE.and(IS_NOT_OPTIONAL)).count();
+            int optionalDepCount = (int)ja.stream().filter(IS_DEP_PREDICATE.and(IS_NOT_OPTIONAL.negate())).count();
             dependencies = getPresizedMutableMap(depCount);
             optionalDependencies = getPresizedMutableMap(optionalDepCount);
 
diff --git a/core/src/main/java/hudson/model/User.java b/core/src/main/java/hudson/model/User.java
index bb9b8c8e44..e14467c42e 100644
--- a/core/src/main/java/hudson/model/User.java
+++ b/core/src/main/java/hudson/model/User.java
@@ -868,7 +868,7 @@ public class User extends AbstractModelObject implements AccessControlled, Descr
         for (UserPropertyDescriptor d : UserProperty.all()) {
             UserProperty p = getProperty(d.clazz);
 
-            JSONObject o = json.optJSONObject("userProperty" + (i++));
+            JSONObject o = json.optJSONObject("userProperty" + i++);
             if (o != null) {
                 if (p != null) {
                     p = p.reconfigure(req, o);
diff --git a/core/src/main/java/hudson/model/View.java b/core/src/main/java/hudson/model/View.java
index e7fd152f58..26b1f2414f 100644
--- a/core/src/main/java/hudson/model/View.java
+++ b/core/src/main/java/hudson/model/View.java
@@ -959,8 +959,8 @@ public abstract class View extends AbstractModelObject implements AccessControll
         for(TopLevelItem item : items) {
             
             if(LOGGER.isLoggable(Level.FINE)) {
-                LOGGER.fine((String.format("Adding url=%s,displayName=%s",
-                            item.getSearchUrl(), item.getDisplayName())));
+                LOGGER.fine(String.format("Adding url=%s,displayName=%s",
+                            item.getSearchUrl(), item.getDisplayName()));
             }
             sib.add(item.getSearchUrl(), item.getDisplayName());
         }        
diff --git a/core/src/main/java/hudson/model/WorkspaceBrowser.java b/core/src/main/java/hudson/model/WorkspaceBrowser.java
index d0c0dac088..582e88bc14 100644
--- a/core/src/main/java/hudson/model/WorkspaceBrowser.java
+++ b/core/src/main/java/hudson/model/WorkspaceBrowser.java
@@ -45,7 +45,6 @@ public abstract class WorkspaceBrowser implements ExtensionPoint {
 
     /**
      * Provide access to job's workspace
-     * @param job
      * @return {@code null} if this WorkspaceBrowser don't have a workspace for this job
      */
     public abstract @CheckForNull FilePath getWorkspace(Job job);
diff --git a/core/src/main/java/hudson/model/WorkspaceListener.java b/core/src/main/java/hudson/model/WorkspaceListener.java
index 94d37d4144..1fce5b907d 100644
--- a/core/src/main/java/hudson/model/WorkspaceListener.java
+++ b/core/src/main/java/hudson/model/WorkspaceListener.java
@@ -8,7 +8,6 @@ public abstract class WorkspaceListener implements ExtensionPoint {
     
     /**
      * Called after a workspace is deleted successfully.
-     * @param project
      */
     public void afterDelete(AbstractProject project) {
         
@@ -16,9 +15,6 @@ public abstract class WorkspaceListener implements ExtensionPoint {
 
     /**
      * Called before a build uses a workspace. IE, before any SCM checkout.
-     * @param b
-     * @param workspace
-     * @param listener 
      */
     public void beforeUse(AbstractBuild b, FilePath workspace, BuildListener listener) {
         
diff --git a/core/src/main/java/hudson/security/GlobalSecurityConfiguration.java b/core/src/main/java/hudson/security/GlobalSecurityConfiguration.java
index 68dc386145..20c3e9a4b8 100644
--- a/core/src/main/java/hudson/security/GlobalSecurityConfiguration.java
+++ b/core/src/main/java/hudson/security/GlobalSecurityConfiguration.java
@@ -199,7 +199,6 @@ public class GlobalSecurityConfiguration extends ManagementLink implements Descr
     public static Predicate<Descriptor> FILTER = input -> input.getCategory() instanceof GlobalConfigurationCategory.Security;
 
     /**
-     * @return
      * @see Describable#getDescriptor()
      */
     @SuppressWarnings("unchecked")
diff --git a/core/src/main/java/hudson/security/csrf/CrumbIssuer.java b/core/src/main/java/hudson/security/csrf/CrumbIssuer.java
index 791d4cc29f..e9efcaf0a4 100644
--- a/core/src/main/java/hudson/security/csrf/CrumbIssuer.java
+++ b/core/src/main/java/hudson/security/csrf/CrumbIssuer.java
@@ -70,7 +70,6 @@ public abstract class CrumbIssuer implements Describable<CrumbIssuer>, Extension
 
     /**
      * Get a crumb value based on user specific information in the request.
-     * @param request
      */
     public String getCrumb(ServletRequest request) {
         String crumb = null;
@@ -99,9 +98,6 @@ public abstract class CrumbIssuer implements Describable<CrumbIssuer>, Extension
      *  <li>the salt value
      *  <li>an implementation specific guarded secret.
      * </ul>
-     *
-     * @param request
-     * @param salt
      */
     protected abstract String issueCrumb(ServletRequest request, String salt);
 
@@ -109,8 +105,6 @@ public abstract class CrumbIssuer implements Describable<CrumbIssuer>, Extension
      * Get a crumb from a request parameter and validate it against other data
      * in the current request. The salt and request parameter that is used is
      * defined by the current configuration.
-     *
-     * @param request
      */
     public boolean validateCrumb(ServletRequest request) {
         CrumbIssuerDescriptor<CrumbIssuer> desc = getDescriptor();
@@ -124,9 +118,6 @@ public abstract class CrumbIssuer implements Describable<CrumbIssuer>, Extension
      * Get a crumb from multipart form data and validate it against other data
      * in the current request. The salt and request parameter that is used is
      * defined by the current configuration.
-     *
-     * @param request
-     * @param parser
      */
     public boolean validateCrumb(ServletRequest request, MultipartFormDataParser parser) {
         CrumbIssuerDescriptor<CrumbIssuer> desc = getDescriptor();
@@ -139,8 +130,6 @@ public abstract class CrumbIssuer implements Describable<CrumbIssuer>, Extension
     /**
      * Validate a previously created crumb against information in the current request.
      *
-     * @param request
-     * @param salt
      * @param crumb The previously generated crumb to validate against information in the current request
      */
     public abstract boolean validateCrumb(ServletRequest request, String salt, String crumb);
diff --git a/core/src/main/java/hudson/security/csrf/CrumbIssuerDescriptor.java b/core/src/main/java/hudson/security/csrf/CrumbIssuerDescriptor.java
index 9e96dd0ff5..c6f1850317 100644
--- a/core/src/main/java/hudson/security/csrf/CrumbIssuerDescriptor.java
+++ b/core/src/main/java/hudson/security/csrf/CrumbIssuerDescriptor.java
@@ -39,7 +39,6 @@ public abstract class CrumbIssuerDescriptor<T extends CrumbIssuer> extends Descr
 
     /**
      * Set the salt value. Must not be null.
-     * @param salt
      */
     public void setCrumbSalt(String salt) {
         if (Util.fixEmptyAndTrim(salt) == null) {
@@ -59,8 +58,6 @@ public abstract class CrumbIssuerDescriptor<T extends CrumbIssuer> extends Descr
 
     /**
      * Set the request parameter name. Must not be null.
-     *
-     * @param requestField
      */
     public void setCrumbRequestField(String requestField) {
         if (Util.fixEmptyAndTrim(requestField) == null) {
diff --git a/core/src/main/java/hudson/triggers/SCMTrigger.java b/core/src/main/java/hudson/triggers/SCMTrigger.java
index 1d955c1c0a..a3b58ffb1a 100644
--- a/core/src/main/java/hudson/triggers/SCMTrigger.java
+++ b/core/src/main/java/hudson/triggers/SCMTrigger.java
@@ -170,7 +170,6 @@ public class SCMTrigger extends Trigger<Item> {
      * Run the SCM trigger with additional build actions. Used by SubversionRepositoryStatus
      * to trigger a build at a specific revision number.
      * 
-     * @param additionalActions
      * @since 1.375
      */
     public void run(Action[] additionalActions) {
diff --git a/core/src/main/java/hudson/util/ChartUtil.java b/core/src/main/java/hudson/util/ChartUtil.java
index 71f40a9427..e1c8f052c6 100644
--- a/core/src/main/java/hudson/util/ChartUtil.java
+++ b/core/src/main/java/hudson/util/ChartUtil.java
@@ -133,9 +133,11 @@ public class ChartUtil {
      * Generates the graph in PNG format and sends that to the response.
      *
      * @param defaultW
+     *      The size of the picture to be generated. These values can be overridden
+     *      by the query parameter 'width' in the request.
      * @param defaultH
      *      The size of the picture to be generated. These values can be overridden
-     *      by the query parameter 'width' and 'height' in the request.
+     *      by the query parameter 'height' in the request.
      * @deprecated as of 1.320
      *      Bind {@link Graph} to the URL space. See {@code hudson.tasks.junit.History} as an example (note that doing so involves
      *      a bit of URL structure change.)
diff --git a/core/src/main/java/hudson/util/ChunkedOutputStream.java b/core/src/main/java/hudson/util/ChunkedOutputStream.java
index d468b75c48..af2e0cedbc 100644
--- a/core/src/main/java/hudson/util/ChunkedOutputStream.java
+++ b/core/src/main/java/hudson/util/ChunkedOutputStream.java
@@ -69,7 +69,6 @@ public class ChunkedOutputStream extends OutputStream {
      * Wraps a stream and chunks the output.
      * @param stream to wrap
      * @param bufferSize minimum chunk size (excluding last chunk)
-     * @throws IOException
      *
      * @since 3.0
      */
@@ -81,8 +80,6 @@ public class ChunkedOutputStream extends OutputStream {
     /**
      * Wraps a stream and chunks the output. The default buffer size of 2048 was chosen because
      * the chunk overhead is less than 0.5%
-     * @param stream
-     * @throws IOException
      */
     public ChunkedOutputStream(OutputStream stream) throws IOException {
         this(stream, 2048);
@@ -91,7 +88,6 @@ public class ChunkedOutputStream extends OutputStream {
     // ----------------------------------------------------------- Internal methods
     /**
      * Writes the cache out onto the underlying stream
-     * @throws IOException
      *
      * @since 3.0
      */
@@ -108,10 +104,6 @@ public class ChunkedOutputStream extends OutputStream {
     /**
      * Writes the cache and bufferToAppend to the underlying stream
      * as one large chunk
-     * @param bufferToAppend
-     * @param off
-     * @param len
-     * @throws IOException
      *
      * @since 3.0
      */
@@ -135,7 +127,6 @@ public class ChunkedOutputStream extends OutputStream {
     // ----------------------------------------------------------- Public Methods
     /**
      * Must be called to ensure the internal cache is flushed and the closing chunk is written.
-     * @throws IOException
      *
      * @since 3.0
      */
@@ -167,8 +158,6 @@ public class ChunkedOutputStream extends OutputStream {
     /**
      * Writes the array. If the array does not fit within the buffer, it is
      * not split, but rather written out as one large chunk.
-     * @param b
-     * @throws IOException
      *
      * @since 3.0
      */
@@ -189,7 +178,6 @@ public class ChunkedOutputStream extends OutputStream {
 
     /**
      * Flushes the underlying stream, but leaves the internal buffer alone.
-     * @throws IOException
      */
     @Override
     public void flush() throws IOException {
@@ -199,7 +187,6 @@ public class ChunkedOutputStream extends OutputStream {
 
     /**
      * Finishes writing to the underlying stream, but does NOT close the underlying stream.
-     * @throws IOException
      */
     @Override
     public void close() throws IOException {
diff --git a/core/src/main/java/hudson/util/ConsistentHash.java b/core/src/main/java/hudson/util/ConsistentHash.java
index 1410e2eca3..e7f3b08024 100644
--- a/core/src/main/java/hudson/util/ConsistentHash.java
+++ b/core/src/main/java/hudson/util/ConsistentHash.java
@@ -157,7 +157,7 @@ public class ConsistentHash<T> {
                     if (!hasNext()) {
                         throw new NoSuchElementException();
                     }
-                    return (T) owner[(start + (pos++)) % owner.length];
+                    return (T) owner[(start + pos++) % owner.length];
                 }
 
                 @Override
diff --git a/core/src/main/java/hudson/util/CopyOnWriteList.java b/core/src/main/java/hudson/util/CopyOnWriteList.java
index 5f5b4565e1..6ee58f856a 100644
--- a/core/src/main/java/hudson/util/CopyOnWriteList.java
+++ b/core/src/main/java/hudson/util/CopyOnWriteList.java
@@ -142,7 +142,7 @@ public class CopyOnWriteList<E> implements Iterable<E> {
         this.core = new ArrayList<>();
     }
 
-    public <E> E[] toArray(E[] array) {
+    public <T> T[] toArray(T[] array) {
         return core.toArray(array);
     }
 
diff --git a/core/src/main/java/hudson/util/CyclicGraphDetector.java b/core/src/main/java/hudson/util/CyclicGraphDetector.java
index 88bb027890..2ebd5f19e5 100644
--- a/core/src/main/java/hudson/util/CyclicGraphDetector.java
+++ b/core/src/main/java/hudson/util/CyclicGraphDetector.java
@@ -65,9 +65,6 @@ public abstract class CyclicGraphDetector<N> {
     
     /**
      * React on detected cycles - default implementation throws an exception.
-     * @param q
-     * @param cycle
-     * @throws CycleDetectedException
      */
     protected void reactOnCycle(N q, List<N> cycle) throws CycleDetectedException{
         throw new CycleDetectedException(cycle);
diff --git a/core/src/main/java/hudson/util/FormValidation.java b/core/src/main/java/hudson/util/FormValidation.java
index d4423b2c47..5f92849a0e 100644
--- a/core/src/main/java/hudson/util/FormValidation.java
+++ b/core/src/main/java/hudson/util/FormValidation.java
@@ -534,7 +534,6 @@ public abstract class FormValidation extends IOException implements HttpResponse
 
     /**
      * Instances should be created via one of the factory methods above.
-     * @param kind
      */
     private FormValidation(Kind kind) {
         this.kind = kind;
diff --git a/core/src/main/java/hudson/util/PersistedList.java b/core/src/main/java/hudson/util/PersistedList.java
index 50fcd1ced3..b39c6239f8 100644
--- a/core/src/main/java/hudson/util/PersistedList.java
+++ b/core/src/main/java/hudson/util/PersistedList.java
@@ -237,7 +237,7 @@ public class PersistedList<T> extends AbstractList<T> {
      * Gets all the {@link Describable}s in an array.
      */
     @Override
-    public <T> T[] toArray(T[] array) {
+    public <X> X[] toArray(X[] array) {
         return data.toArray(array);
     }
 
diff --git a/core/src/main/java/hudson/util/Secret.java b/core/src/main/java/hudson/util/Secret.java
index e2800ab756..5f371085ba 100644
--- a/core/src/main/java/hudson/util/Secret.java
+++ b/core/src/main/java/hudson/util/Secret.java
@@ -141,11 +141,11 @@ public final class Secret implements Serializable {
             payload[pos++] = (byte)(iv.length >> 24);
             payload[pos++] = (byte)(iv.length >> 16);
             payload[pos++] = (byte)(iv.length >> 8);
-            payload[pos++] = (byte)(iv.length);
+            payload[pos++] = (byte)iv.length;
             payload[pos++] = (byte)(encrypted.length >> 24);
             payload[pos++] = (byte)(encrypted.length >> 16);
             payload[pos++] = (byte)(encrypted.length >> 8);
-            payload[pos++] = (byte)(encrypted.length);
+            payload[pos++] = (byte)encrypted.length;
             System.arraycopy(iv, 0, payload, pos, iv.length);
             pos+=iv.length;
             System.arraycopy(encrypted, 0, payload, pos, encrypted.length);
diff --git a/core/src/main/java/hudson/util/SecretRewriter.java b/core/src/main/java/hudson/util/SecretRewriter.java
index ec9206e865..ffb417a781 100644
--- a/core/src/main/java/hudson/util/SecretRewriter.java
+++ b/core/src/main/java/hudson/util/SecretRewriter.java
@@ -156,7 +156,7 @@ public class SecretRewriter {
             for (File child : children) {
                 String cn = child.getName();
                 if (cn.endsWith(".xml")) {
-                    if ((count++)%100==0)
+                    if (count++ % 100 == 0)
                         listener.getLogger().println("Scanning "+child);
                     try {
                         if (rewrite(child)) {
diff --git a/core/src/main/java/hudson/util/UnbufferedBase64InputStream.java b/core/src/main/java/hudson/util/UnbufferedBase64InputStream.java
index 638d439d22..54b46279f4 100644
--- a/core/src/main/java/hudson/util/UnbufferedBase64InputStream.java
+++ b/core/src/main/java/hudson/util/UnbufferedBase64InputStream.java
@@ -45,7 +45,7 @@ public class UnbufferedBase64InputStream extends FilterInputStream {
             pos = 0;
         }
 
-        return (decoded[pos++])&0xFF;
+        return decoded[pos++] & 0xFF;
     }
 
     @Override
diff --git a/core/src/main/java/hudson/util/jna/WINNT.java b/core/src/main/java/hudson/util/jna/WINNT.java
index ce484db6ce..bcfd651676 100644
--- a/core/src/main/java/hudson/util/jna/WINNT.java
+++ b/core/src/main/java/hudson/util/jna/WINNT.java
@@ -47,8 +47,8 @@ public interface WINNT {
   int KEY_NOTIFY             = 0x0010;
   int KEY_CREATE_LINK        = 0x0020;
 
-  int KEY_READ  = ((STANDARD_RIGHTS_READ | KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS | KEY_NOTIFY) & (~SYNCHRONIZE));
-  int KEY_WRITE = ((STANDARD_RIGHTS_WRITE | KEY_SET_VALUE | KEY_CREATE_SUB_KEY) & (~SYNCHRONIZE));
+  int KEY_READ  = ((STANDARD_RIGHTS_READ | KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS | KEY_NOTIFY) & ~SYNCHRONIZE);
+  int KEY_WRITE = ((STANDARD_RIGHTS_WRITE | KEY_SET_VALUE | KEY_CREATE_SUB_KEY) & ~SYNCHRONIZE);
 
   int REG_NONE                       = 0;   // No value type
   int REG_SZ                         = 1;   // Unicode nul terminated string
diff --git a/core/src/main/java/jenkins/PluginLocaleDrivenResourceProvider.java b/core/src/main/java/jenkins/PluginLocaleDrivenResourceProvider.java
index 03897b67c7..b13365eacb 100644
--- a/core/src/main/java/jenkins/PluginLocaleDrivenResourceProvider.java
+++ b/core/src/main/java/jenkins/PluginLocaleDrivenResourceProvider.java
@@ -40,7 +40,6 @@ public interface PluginLocaleDrivenResourceProvider extends ExtensionPoint {
      *
      * @see org.kohsuke.stapler.LocaleDrivenResourceProvider
      *
-     * @param s
      * @return URL to the localized resource, or {@code null} if inapplicable.
      */
     @CheckForNull
diff --git a/core/src/main/java/jenkins/install/InstallState.java b/core/src/main/java/jenkins/install/InstallState.java
index 367017dd06..d0e3a05ad6 100644
--- a/core/src/main/java/jenkins/install/InstallState.java
+++ b/core/src/main/java/jenkins/install/InstallState.java
@@ -346,8 +346,6 @@ public class InstallState implements ExtensionPoint {
 
     /**
      * Find an install state by name
-     * @param name
-     * @return
      */
     @CheckForNull
     public static InstallState valueOf(@NonNull String name) {
diff --git a/core/src/main/java/jenkins/install/InstallUtil.java b/core/src/main/java/jenkins/install/InstallUtil.java
index 64e366bc0e..1151e96c31 100644
--- a/core/src/main/java/jenkins/install/InstallUtil.java
+++ b/core/src/main/java/jenkins/install/InstallUtil.java
@@ -298,7 +298,6 @@ public class InstallUtil {
 
     /**
      * Persists a list of installing plugins; this is used in the case Jenkins fails mid-installation and needs to be restarted
-     * @param installingPlugins
      */
     public static synchronized void persistInstallStatus(List<UpdateCenterJob> installingPlugins) {
         File installingPluginsFile = getInstallingPluginsFile();
diff --git a/core/src/main/java/jenkins/model/GlobalBuildDiscarderStrategy.java b/core/src/main/java/jenkins/model/GlobalBuildDiscarderStrategy.java
index 124b26ef5e..4e2781ba4a 100644
--- a/core/src/main/java/jenkins/model/GlobalBuildDiscarderStrategy.java
+++ b/core/src/main/java/jenkins/model/GlobalBuildDiscarderStrategy.java
@@ -44,7 +44,6 @@ public abstract class GlobalBuildDiscarderStrategy extends AbstractDescribableIm
 
     /**
      * Returns true if and only if this strategy applies to the given job.
-     * @param job
      * @return true if and only if this strategy applies to the given job.
      */
     public abstract boolean isApplicable(Job<?, ?> job);
@@ -53,10 +52,6 @@ public abstract class GlobalBuildDiscarderStrategy extends AbstractDescribableIm
      * Applies this build discarder strategy to the given job, i.e. delete builds based on this strategy's configuration.
      *
      * The default implementation calls {@link #apply(Run)} on each build.
-     *
-     * @param job
-     * @throws IOException
-     * @throws InterruptedException
      */
     public void apply(Job<? extends Job, ? extends Run> job) throws IOException, InterruptedException {
         for (Run<? extends Job, ? extends Run> run : job.getBuilds()) {
@@ -70,10 +65,6 @@ public abstract class GlobalBuildDiscarderStrategy extends AbstractDescribableIm
 
     /**
      * Applies this build discarder strategy to the given run, i.e. delete builds based on this strategy's configuration.
-     *
-     * @param run
-     * @throws IOException
-     * @throws InterruptedException
      */
     public void apply(Run<?, ?> run) throws IOException, InterruptedException {
         // no-op by default
diff --git a/core/src/main/java/jenkins/model/IdStrategy.java b/core/src/main/java/jenkins/model/IdStrategy.java
index c46711355d..a672c095db 100644
--- a/core/src/main/java/jenkins/model/IdStrategy.java
+++ b/core/src/main/java/jenkins/model/IdStrategy.java
@@ -297,7 +297,7 @@ public abstract class IdStrategy extends AbstractDescribableImpl<IdStrategy> imp
         public String keyFor(@NonNull String id) {
             int index = id.lastIndexOf('@'); // The @ can be used in local-part if quoted correctly
             // => the last @ is the one used to separate the domain and local-part
-            return index == -1 ? id : id.substring(0, index) + (id.substring(index).toLowerCase(Locale.ENGLISH));
+            return index == -1 ? id : id.substring(0, index) + id.substring(index).toLowerCase(Locale.ENGLISH);
         }
 
         @Override
diff --git a/core/src/main/java/jenkins/model/Jenkins.java b/core/src/main/java/jenkins/model/Jenkins.java
index 484c5dec89..83f8325431 100644
--- a/core/src/main/java/jenkins/model/Jenkins.java
+++ b/core/src/main/java/jenkins/model/Jenkins.java
@@ -4946,7 +4946,7 @@ public class Jenkins extends AbstractCIBase implements DirectlyModifiableTopLeve
         }
 
         // TODO SlaveComputer.doSlaveAgentJnlp; there should be an annotation to request unprotected access
-        if ((isAgentJnlpPath(restOfPath, "jenkins") || (isAgentJnlpPath(restOfPath, "slave")))
+        if ((isAgentJnlpPath(restOfPath, "jenkins") || isAgentJnlpPath(restOfPath, "slave"))
             && "true".equals(Stapler.getCurrentRequest().getParameter("encrypt"))) {
             return false;
         }
@@ -4992,8 +4992,6 @@ public class Jenkins extends AbstractCIBase implements DirectlyModifiableTopLeve
      * unique. It does not check the displayName against the displayName of the
      * job that the user is configuring though to prevent a validation warning
      * if the user sets the displayName to what it currently is.
-     * @param displayName
-     * @param currentJobName
      */
     boolean isDisplayNameUnique(String displayName, String currentJobName) {
         Collection<TopLevelItem> itemCollection = items.values();
diff --git a/core/src/main/java/jenkins/model/Nodes.java b/core/src/main/java/jenkins/model/Nodes.java
index ddaf78060b..5e4ff79227 100644
--- a/core/src/main/java/jenkins/model/Nodes.java
+++ b/core/src/main/java/jenkins/model/Nodes.java
@@ -369,7 +369,6 @@ public class Nodes implements Saveable {
      * Returns the directory that the nodes are stored in.
      *
      * @return the directory that the nodes are stored in.
-     * @throws IOException
      */
     private File getNodesDir() throws IOException {
         final File nodesDir = new File(jenkins.getRootDir(), "nodes");
diff --git a/core/src/main/java/jenkins/mvn/SettingsProvider.java b/core/src/main/java/jenkins/mvn/SettingsProvider.java
index a84e6469bb..a87e2013b2 100644
--- a/core/src/main/java/jenkins/mvn/SettingsProvider.java
+++ b/core/src/main/java/jenkins/mvn/SettingsProvider.java
@@ -23,7 +23,6 @@ public abstract class SettingsProvider extends AbstractDescribableImpl<SettingsP
     /**
      * Configure maven launcher argument list with adequate settings path. Implementations should be aware that this method might get called multiple times during a build.
      * 
-     * @param build
      * @return the filepath to the provided file. {@code null} if no settings will be provided.
      */
     public abstract FilePath supplySettings(AbstractBuild<?, ?> build, TaskListener listener);
diff --git a/core/src/main/java/jenkins/security/QueueItemAuthenticatorProvider.java b/core/src/main/java/jenkins/security/QueueItemAuthenticatorProvider.java
index 4243406344..ec28c90ecc 100644
--- a/core/src/main/java/jenkins/security/QueueItemAuthenticatorProvider.java
+++ b/core/src/main/java/jenkins/security/QueueItemAuthenticatorProvider.java
@@ -36,7 +36,7 @@ public abstract class QueueItemAuthenticatorProvider implements ExtensionPoint {
 
         @Override
         public boolean hasNext() {
-            while ((delegate == null || !delegate.hasNext()) && (providers.hasNext())) {
+            while ((delegate == null || !delegate.hasNext()) && providers.hasNext()) {
                 final QueueItemAuthenticatorProvider provider = providers.next();
                 if (provider == null) {
                     continue;
diff --git a/core/src/test/java/hudson/FilePathTest.java b/core/src/test/java/hudson/FilePathTest.java
index 09cf44312e..146198acd1 100644
--- a/core/src/test/java/hudson/FilePathTest.java
+++ b/core/src/test/java/hudson/FilePathTest.java
@@ -31,6 +31,7 @@ import hudson.remoting.VirtualChannel;
 import hudson.slaves.WorkspaceList;
 import hudson.util.NullStream;
 import hudson.util.StreamTaskListener;
+import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.output.NullOutputStream;
 import org.apache.tools.ant.Project;
@@ -168,7 +169,7 @@ public class FilePathTest {
                 public Integer call() throws Exception {
                     class Sink extends OutputStream {
                         private Exception closed;
-                        private volatile int count;
+                        private final AtomicInteger count = new AtomicInteger();
 
                         private void checkNotClosed() throws IOException {
                             if (closed != null)
@@ -177,19 +178,19 @@ public class FilePathTest {
 
                         @Override
                         public void write(int b) throws IOException {
-                            count++;
+                            count.incrementAndGet();
                             checkNotClosed();
                         }
 
                         @Override
                         public void write(byte[] b) throws IOException {
-                            count+=b.length;
+                            count.addAndGet(b.length);
                             checkNotClosed();
                         }
 
                         @Override
                         public void write(byte[] b, int off, int len) throws IOException {
-                            count+=len;
+                            count.addAndGet(len);
                             checkNotClosed();
                         }
 
@@ -204,7 +205,7 @@ public class FilePathTest {
                     FilePath f = new FilePath(channels.french, file.getPath());
                     Sink sink = new Sink();
                     f.copyTo(sink);
-                    return sink.count;
+                    return sink.count.get();
                 }
             });
         }
diff --git a/core/src/test/java/hudson/FunctionsTest.java b/core/src/test/java/hudson/FunctionsTest.java
index 05b636718d..3d50a00f5d 100644
--- a/core/src/test/java/hudson/FunctionsTest.java
+++ b/core/src/test/java/hudson/FunctionsTest.java
@@ -521,7 +521,7 @@ public class FunctionsTest {
         stack2.cause(stack1);
         //Format changed in 11.0.9 / 8.0.272 (JDK-8226809 / JDK-8252444 / JDK-8252489)
 
-        if ((getVersion().isNewerThanOrEqualTo(new VersionNumber("11.0.9"))) ||
+        if (getVersion().isNewerThanOrEqualTo(new VersionNumber("11.0.9")) ||
                 (getVersion().getDigitAt(0) == 8 && getVersion().isNewerThanOrEqualTo(new VersionNumber("8.0.272")))) {
             assertPrintThrowable(stack1,
                     "p.Exc1\n" +
diff --git a/core/src/test/java/hudson/util/ArgumentListBuilderTest.java b/core/src/test/java/hudson/util/ArgumentListBuilderTest.java
index 40d3562224..3571dc8155 100644
--- a/core/src/test/java/hudson/util/ArgumentListBuilderTest.java
+++ b/core/src/test/java/hudson/util/ArgumentListBuilderTest.java
@@ -32,8 +32,8 @@ import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
+import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
@@ -171,15 +171,14 @@ public class ArgumentListBuilderTest {
         assertThat("The mask array was incorrect", array, is(builder.toMaskArray()));
     }
     
-    private static final Map<String, String> KEY_VALUES = new LinkedHashMap<String, String>() {{
-        put("key1", "value1");
-        put("key2", "value2");
-        put("key3", "value3");
-    }};
+    private static final Map<String, String> KEY_VALUES = new LinkedHashMap<>();
+    static {
+        KEY_VALUES.put("key1", "value1");
+        KEY_VALUES.put("key2", "value2");
+        KEY_VALUES.put("key3", "value3");
+    }
 
-    private static final Set<String> MASKS = new HashSet<String>() {{
-        add("key2");
-    }};
+    private static final Set<String> MASKS = Collections.singleton("key2");
     
     @Test
     public void assertKeyValuePairsWithMask() {
diff --git a/core/src/test/java/hudson/util/SecretRewriterTest.java b/core/src/test/java/hudson/util/SecretRewriterTest.java
index 817c83c43e..1f2c004f25 100644
--- a/core/src/test/java/hudson/util/SecretRewriterTest.java
+++ b/core/src/test/java/hudson/util/SecretRewriterTest.java
@@ -4,7 +4,6 @@ import hudson.FilePath;
 import hudson.Functions;
 import hudson.model.TaskListener;
 import java.io.File;
-import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
@@ -87,11 +86,7 @@ public class SecretRewriterTest {
         for (String p : dirs) {
             File d = new File(t, p);
             d.mkdir();
-            try {
-                FileUtils.write(new File(d, "foo.xml"), payload, Charset.defaultCharset());
-            } catch (IOException x) {
-                assert false : x;
-            }
+            FileUtils.write(new File(d, "foo.xml"), payload, Charset.defaultCharset());
         }
 
         // stuff outside
diff --git a/core/src/test/java/jenkins/model/RunIdMigratorTest.java b/core/src/test/java/jenkins/model/RunIdMigratorTest.java
index 0922091e79..02378ef6e6 100644
--- a/core/src/test/java/jenkins/model/RunIdMigratorTest.java
+++ b/core/src/test/java/jenkins/model/RunIdMigratorTest.java
@@ -37,6 +37,7 @@ import java.util.logging.ConsoleHandler;
 import java.util.logging.Handler;
 import java.util.logging.Level;
 import org.apache.commons.io.FileUtils;
+import org.junit.AfterClass;
 import org.junit.Test;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -53,9 +54,16 @@ public class RunIdMigratorTest {
 
     @Rule public TemporaryFolder tmp = new TemporaryFolder();
 
+    private static TimeZone defaultTimezone;
+
     /** Ensures that legacy timestamps are interpreted in a predictable time zone. */
     @BeforeClass public static void timezone() {
-        TimeZone.setDefault(TimeZone.getTimeZone("EST"));
+        defaultTimezone = TimeZone.getDefault();
+        TimeZone.setDefault(TimeZone.getTimeZone("America/New_York"));
+    }
+
+    @AfterClass public static void tearDown() {
+        TimeZone.setDefault(defaultTimezone);
     }
 
     // TODO could use LoggerRule only if it were extracted to an independent library
diff --git a/core/src/test/java/jenkins/util/AtmostOneTaskExecutorTest.java b/core/src/test/java/jenkins/util/AtmostOneTaskExecutorTest.java
index 2bd586227d..5028900d8b 100644
--- a/core/src/test/java/jenkins/util/AtmostOneTaskExecutorTest.java
+++ b/core/src/test/java/jenkins/util/AtmostOneTaskExecutorTest.java
@@ -27,7 +27,7 @@ public class AtmostOneTaskExecutorTest {
             try {
                 lock.block();
             } catch (InterruptedException x) {
-                assert false : x;
+                throw new RuntimeException(x);
             }
             return null;
         });
diff --git a/test/src/test/java/hudson/PluginManagerTest.java b/test/src/test/java/hudson/PluginManagerTest.java
index eb3447aa6f..74a07bb931 100644
--- a/test/src/test/java/hudson/PluginManagerTest.java
+++ b/test/src/test/java/hudson/PluginManagerTest.java
@@ -254,9 +254,6 @@ public class PluginManagerTest {
     
     /**
      * call org.jenkinsci.plugins.dependencytest.depender.Depender.getValue().
-     * 
-     * @return
-     * @throws Exception
      */
     private String callDependerValue() throws Exception {
         Class<?> c = r.jenkins.getPluginManager().uberClassLoader.loadClass("org.jenkinsci.plugins.dependencytest.depender.Depender");
@@ -267,8 +264,6 @@ public class PluginManagerTest {
     /**
      * Load "dependee" and then load "depender".
      * Asserts that "depender" can access to "dependee".
-     * 
-     * @throws Exception
      */
     @Test public void installDependingPluginWithoutRestart() throws Exception {
         // Load dependee.
@@ -301,8 +296,6 @@ public class PluginManagerTest {
     /**
      * Load "depender" and then load "dependee".
      * Asserts that "depender" can access to "dependee".
-     * 
-     * @throws Exception
      */
     @Issue("JENKINS-19976")
     @Test public void installDependedPluginWithoutRestart() throws Exception {
@@ -342,8 +335,6 @@ public class PluginManagerTest {
     /**
      * Load "optional-depender" and then load "dependee".
      * Asserts that "depender" can access to "dependee".
-     *
-     * @throws Exception
      */
     @Issue("JENKINS-60449")
     @WithPlugin("variant.hpi")
@@ -545,8 +536,8 @@ public class PluginManagerTest {
                 if(job instanceof UpdateCenter.DownloadJob) {
 		    UpdateCenter.DownloadJob j = (UpdateCenter.DownloadJob)job;
 		    assertFalse(j.status instanceof UpdateCenter.DownloadJob.Failure);
-                    done &= !(((j.status instanceof UpdateCenter.DownloadJob.Pending) || 
-			(j.status instanceof UpdateCenter.DownloadJob.Installing)));
+                    done &= !((j.status instanceof UpdateCenter.DownloadJob.Pending) || 
+			(j.status instanceof UpdateCenter.DownloadJob.Installing));
                 }		
             }
         } while(!done);
diff --git a/test/src/test/java/hudson/cli/QuietDownCommandTest.java b/test/src/test/java/hudson/cli/QuietDownCommandTest.java
index ca69dce2c1..ae391ef59d 100644
--- a/test/src/test/java/hudson/cli/QuietDownCommandTest.java
+++ b/test/src/test/java/hudson/cli/QuietDownCommandTest.java
@@ -506,7 +506,6 @@ public class QuietDownCommandTest {
 
     /**
      * Asserts if Jenkins is in quiet mode, retrying for some time before failing.
-     * @throws TimeoutException
      */
     public static void assertJenkinsInQuietMode(final JenkinsRule j) {
         await().pollInterval(250, TimeUnit.MILLISECONDS)
@@ -516,7 +515,6 @@ public class QuietDownCommandTest {
 
     /**
      * Asserts if Jenkins is <strong>not</strong> in quiet mode, retrying for some time before failing.
-     * @throws TimeoutException
      */
     public static void assertJenkinsNotInQuietMode(final JenkinsRule j) {
         await().pollInterval(250, TimeUnit.MILLISECONDS)
diff --git a/test/src/test/java/hudson/cli/UpdateViewCommandTest.java b/test/src/test/java/hudson/cli/UpdateViewCommandTest.java
index 57a0a35040..857b67f352 100644
--- a/test/src/test/java/hudson/cli/UpdateViewCommandTest.java
+++ b/test/src/test/java/hudson/cli/UpdateViewCommandTest.java
@@ -71,8 +71,6 @@ public class UpdateViewCommandTest {
     /**
      * This test shows that updating a view using an XML that will be
      * converted by XStream via an alias will rightfully succeed.
-     *
-     * @throws Exception
      */
     @Test public void updateViewWithRenamedClass() throws Exception {
         ListView tv  = new ListView("tView");
diff --git a/test/src/test/java/hudson/console/ConsoleAnnotatorTest.java b/test/src/test/java/hudson/console/ConsoleAnnotatorTest.java
index 729f7969c0..541e284c1f 100644
--- a/test/src/test/java/hudson/console/ConsoleAnnotatorTest.java
+++ b/test/src/test/java/hudson/console/ConsoleAnnotatorTest.java
@@ -219,7 +219,7 @@ public class ConsoleAnnotatorTest {
         @Override
         public ConsoleAnnotator annotate(Object build, MarkupText text) {
             if (text.getText().startsWith("line"))
-                text.addMarkup(0,5,"<b tag="+(n++)+">","</b>");
+                text.addMarkup(0, 5, "<b tag=" + n++ + ">", "</b>");
             return this;
         }
     }
diff --git a/test/src/test/java/hudson/model/AbstractBuildTest.java b/test/src/test/java/hudson/model/AbstractBuildTest.java
index d2711e98b9..e026fe9316 100644
--- a/test/src/test/java/hudson/model/AbstractBuildTest.java
+++ b/test/src/test/java/hudson/model/AbstractBuildTest.java
@@ -303,9 +303,10 @@ public class AbstractBuildTest {
             public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
                 if (build.number == 1) {
                     e1.signal();  // signal that build #1 is in publisher
+                } else if (build.number == 2) {
+                    e2.signal();  // signal that build #2 is in publisher
                 } else {
-                    assert build.number == 2;
-                    e2.signal();
+                    throw new IllegalArgumentException("unexpected build number: " + build.number);
                 }
 
                 done.block();
diff --git a/test/src/test/java/hudson/model/ComputerConfigDotXmlTest.java b/test/src/test/java/hudson/model/ComputerConfigDotXmlTest.java
index 423238afa8..faf7bb5368 100644
--- a/test/src/test/java/hudson/model/ComputerConfigDotXmlTest.java
+++ b/test/src/test/java/hudson/model/ComputerConfigDotXmlTest.java
@@ -276,6 +276,16 @@ public class ComputerConfigDotXmlTest {
                 return inner.read();
             }
 
+            @Override
+            public int read(byte[] b) throws IOException {
+                return inner.read(b);
+            }
+
+            @Override
+            public int read(byte[] b, int off, int len) throws IOException {
+                return inner.read(b, off, len);
+            }
+
             @Override
             public boolean isFinished() {
                 return false;
diff --git a/test/src/test/java/hudson/model/DescriptorVisibilityFilterTest.java b/test/src/test/java/hudson/model/DescriptorVisibilityFilterTest.java
index b014e52ea0..207a7c6677 100644
--- a/test/src/test/java/hudson/model/DescriptorVisibilityFilterTest.java
+++ b/test/src/test/java/hudson/model/DescriptorVisibilityFilterTest.java
@@ -77,7 +77,7 @@ public class DescriptorVisibilityFilterTest {
         public static final class HideDescriptor extends DescriptorVisibilityFilter {
             @Override
             public boolean filter(@CheckForNull Object context, @NonNull Descriptor descriptor) {
-                return !(descriptor instanceof DescriptorImpl);
+                return !(descriptor instanceof TestSecurityRealm.DescriptorImpl);
             }
         }
     }
@@ -105,7 +105,7 @@ public class DescriptorVisibilityFilterTest {
         public static final class HideDescriptor extends DescriptorVisibilityFilter {
             @Override
             public boolean filter(@CheckForNull Object context, @NonNull Descriptor descriptor) {
-                return !(descriptor instanceof DescriptorImpl);
+                return !(descriptor instanceof TestAuthStrategy.DescriptorImpl);
             }
         }
     }
diff --git a/test/src/test/java/hudson/model/ListViewTest.java b/test/src/test/java/hudson/model/ListViewTest.java
index 6ab4647dce..7437b88d6d 100644
--- a/test/src/test/java/hudson/model/ListViewTest.java
+++ b/test/src/test/java/hudson/model/ListViewTest.java
@@ -400,6 +400,15 @@ public class ListViewTest {
             return inner.read();
         }
         @Override
+        public int read(byte[] b) throws IOException {
+            return inner.read(b);
+        }
+
+        @Override
+        public int read(byte[] b, int off, int len) throws IOException {
+            return inner.read(b, off, len);
+        }
+        @Override
         public boolean isFinished() {
             throw new UnsupportedOperationException();
         }
diff --git a/test/src/test/java/hudson/model/ProjectTest.java b/test/src/test/java/hudson/model/ProjectTest.java
index 34691d7a30..2a181abe87 100644
--- a/test/src/test/java/hudson/model/ProjectTest.java
+++ b/test/src/test/java/hudson/model/ProjectTest.java
@@ -556,7 +556,7 @@ public class ProjectTest {
             fail("User should not have permission to build project");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         } 
@@ -575,7 +575,7 @@ public class ProjectTest {
             fail("User should not have permission to build project");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         } 
@@ -612,7 +612,7 @@ public class ProjectTest {
             fail("User should not have permission to build project");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         } 
@@ -650,7 +650,7 @@ public class ProjectTest {
             fail("User should not have permission to build project");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         } 
@@ -688,7 +688,7 @@ public class ProjectTest {
             fail("User should not have permission to build project");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         } 
@@ -711,7 +711,6 @@ public class ProjectTest {
     
     /**
      * Job is un-restricted (no nabel), this is submitted to queue, which spawns an on demand slave
-     * @throws Exception 
      */
     @Test
     public void testJobSubmittedShouldSpawnCloud() throws Exception {
@@ -741,7 +740,6 @@ public class ProjectTest {
     
     /**
      * Job is restricted, but label can not be provided by any cloud, only normal agents. Then job will not submit, because no slave is available.
-     * @throws Exception
      */
     @Test
     public void testUnrestrictedJobNoLabelByCloudNoQueue() throws Exception {
@@ -786,7 +784,6 @@ public class ProjectTest {
     
     /**
      * Job is restricted. Label is on slave that can be started in cloud. Job is submitted to queue, which spawns an on demand slave.
-     * @throws Exception 
      */
     @Test
     public void testRestrictedLabelOnSlaveYesQueue() throws Exception {        
diff --git a/test/src/test/java/hudson/model/UpdateSiteTest.java b/test/src/test/java/hudson/model/UpdateSiteTest.java
index e31c344dde..20b935ac9b 100644
--- a/test/src/test/java/hudson/model/UpdateSiteTest.java
+++ b/test/src/test/java/hudson/model/UpdateSiteTest.java
@@ -86,7 +86,6 @@ public class UpdateSiteTest {
 
     /**
      * Startup a web server to access resources via HTTP.
-     * @throws Exception 
      */
     @Before
     public void setUpWebServer() throws Exception {
diff --git a/test/src/test/java/hudson/model/UsageStatisticsTest.java b/test/src/test/java/hudson/model/UsageStatisticsTest.java
index 4db0536d64..2c48648ebe 100644
--- a/test/src/test/java/hudson/model/UsageStatisticsTest.java
+++ b/test/src/test/java/hudson/model/UsageStatisticsTest.java
@@ -135,8 +135,6 @@ public class UsageStatisticsTest {
      * a background update of that cache.
      * <p/>
      * <p>This method triggers that update and waits until the cache is filled during roughly 1 second max.</p>
-     *
-     * @throws InterruptedException
      */
     private void warmUpNodeMonitorCache() throws InterruptedException {
         ArchitectureMonitor.DescriptorImpl descriptor = j.jenkins.getDescriptorByType(ArchitectureMonitor.DescriptorImpl.class);
diff --git a/test/src/test/java/hudson/model/UserTest.java b/test/src/test/java/hudson/model/UserTest.java
index 1a0afc80a2..e409bb8c85 100644
--- a/test/src/test/java/hudson/model/UserTest.java
+++ b/test/src/test/java/hudson/model/UserTest.java
@@ -416,7 +416,7 @@ public class UserTest {
             fail("User should not have permission to configure another user.");
         }
         catch(Exception e){
-            if(!(e.getClass().isAssignableFrom(AccessDeniedException3.class))){
+            if(!e.getClass().isAssignableFrom(AccessDeniedException3.class)){
                fail("AccessDeniedException should be thrown.");
             }
         }
diff --git a/test/src/test/java/hudson/model/listeners/ItemListenerTest.java b/test/src/test/java/hudson/model/listeners/ItemListenerTest.java
index 415320088d..d75da79ce2 100644
--- a/test/src/test/java/hudson/model/listeners/ItemListenerTest.java
+++ b/test/src/test/java/hudson/model/listeners/ItemListenerTest.java
@@ -61,7 +61,7 @@ public class ItemListenerTest {
     @Test
     public void onCreatedViaCLI() throws Exception {
         CLICommandInvoker.Result result = new CLICommandInvoker(j, "create-job").
-                withStdin(new ByteArrayInputStream(("<project><actions/><builders/><publishers/><buildWrappers/></project>").getBytes())).
+                withStdin(new ByteArrayInputStream("<project><actions/><builders/><publishers/><buildWrappers/></project>".getBytes())).
                 invokeWithArgs("testJob");
         assertThat(result, CLICommandInvoker.Matcher.succeeded());
         assertNotNull("job should be created: " + result, j.jenkins.getItem("testJob"));
diff --git a/test/src/test/java/hudson/scm/ChangeLogSetTest.java b/test/src/test/java/hudson/scm/ChangeLogSetTest.java
index 0f8aa10fa1..0bc61e0624 100644
--- a/test/src/test/java/hudson/scm/ChangeLogSetTest.java
+++ b/test/src/test/java/hudson/scm/ChangeLogSetTest.java
@@ -28,7 +28,7 @@ public class ChangeLogSetTest {
         } catch (Throwable t) {
             fail(t.getMessage());
         }
-        assertEquals((new FakeChangeLogSCM.EntryImpl()).getMsg(), change.getMsg());
+        assertEquals(new FakeChangeLogSCM.EntryImpl().getMsg(), change.getMsg());
     }
 
     @Extension
diff --git a/test/src/test/java/hudson/slaves/EnvironmentVariableNodePropertyTest.java b/test/src/test/java/hudson/slaves/EnvironmentVariableNodePropertyTest.java
index a86125db76..503ffe0fa4 100644
--- a/test/src/test/java/hudson/slaves/EnvironmentVariableNodePropertyTest.java
+++ b/test/src/test/java/hudson/slaves/EnvironmentVariableNodePropertyTest.java
@@ -83,7 +83,6 @@ public class EnvironmentVariableNodePropertyTest {
 	/**
 	 * Agent and master properties and parameters are available.
 	 * Priority: parameters > agent > master
-	 * @throws Exception
 	 */
 	@Test
 	public void testSlaveAndMasterPropertyAndParameterOnSlave()
diff --git a/test/src/test/java/hudson/util/XStream2Security383Test.java b/test/src/test/java/hudson/util/XStream2Security383Test.java
index 614ddde757..940309d736 100644
--- a/test/src/test/java/hudson/util/XStream2Security383Test.java
+++ b/test/src/test/java/hudson/util/XStream2Security383Test.java
@@ -125,6 +125,14 @@ public class XStream2Security383Test {
             return inner.read();
         }
         @Override
+        public int read(byte[] b) throws IOException {
+            return inner.read(b);
+        }
+        @Override
+        public int read(byte[] b, int off, int len) throws IOException {
+            return inner.read(b, off, len);
+        }
+        @Override
         public boolean isFinished() {
             throw new UnsupportedOperationException();
         }
diff --git a/test/src/test/java/jenkins/AgentProtocolTest.java b/test/src/test/java/jenkins/AgentProtocolTest.java
index c8b5d7f079..68984dc3e4 100644
--- a/test/src/test/java/jenkins/AgentProtocolTest.java
+++ b/test/src/test/java/jenkins/AgentProtocolTest.java
@@ -73,7 +73,7 @@ public class AgentProtocolTest {
         Set<String> agentProtocols = jenkins.getAgentProtocols();
         List<String> failedChecks = new ArrayList<>();
         for (String protocol : protocolNames) {
-            if (shouldBeEnabled && !(agentProtocols.contains(protocol))) {
+            if (shouldBeEnabled && !agentProtocols.contains(protocol)) {
                 failedChecks.add(protocol);
             }
             if (!shouldBeEnabled && agentProtocols.contains(protocol)) {
diff --git a/test/src/test/java/jenkins/security/Security857Test.java b/test/src/test/java/jenkins/security/Security857Test.java
index f62a20cb46..d81f4a87b3 100644
--- a/test/src/test/java/jenkins/security/Security857Test.java
+++ b/test/src/test/java/jenkins/security/Security857Test.java
@@ -25,7 +25,6 @@ public class Security857Test {
 
     /**
      * Test that a jelly is escaped right thanks to the CustomJellyContext.ESCAPE_BY_DEFAULT field. Its default value is true.
-     * @throws Exception
      */
     @Issue("SECURITY-857")
     @Test
@@ -35,7 +34,6 @@ public class Security857Test {
 
     /**
      * Test that a jelly is not escaped when the escape-by-default='false' directive is set in it.
-     * @throws Exception
      */
     @Issue("SECURITY-857")
     @Test
@@ -46,7 +44,6 @@ public class Security857Test {
 
     /**
      * Test that a jelly is escaped when the escape-by-default='true' directive is set in it.
-     * @throws Exception
      */
     @Issue("SECURITY-857")
     @Test
diff --git a/test/src/test/java/jenkins/security/stapler/DoActionFilterTest.java b/test/src/test/java/jenkins/security/stapler/DoActionFilterTest.java
index 47d5900c77..5025e8d32d 100644
--- a/test/src/test/java/jenkins/security/stapler/DoActionFilterTest.java
+++ b/test/src/test/java/jenkins/security/stapler/DoActionFilterTest.java
@@ -45,7 +45,6 @@ import java.net.URL;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Enumeration;
-import java.util.HashMap;
 import java.util.Map;
 
 import static org.junit.Assert.assertEquals;
@@ -166,9 +165,7 @@ public class DoActionFilterTest extends StaplerAbstractTest {
         
         @JsonResponse // does not support list
         public Map<String, Object> doAnnotatedJsonResponse() {
-            return new HashMap<String, Object>() {{
-                put("a", "b");
-            }};
+            return Collections.singletonMap("a", "b");
         }
         
         @LimitedTo("admin")
@@ -387,9 +384,7 @@ public class DoActionFilterTest extends StaplerAbstractTest {
         // WebClient forces us to use POST to have the possibility to send requestBody
         settings.setHttpMethod(HttpMethod.POST);
         settings.setAdditionalHeader("Content-Type", "application/json");
-        settings.setRequestBody(JSONObject.fromObject(new HashMap<String, Object>() {{
-            put("name", "Test");
-        }}).toString());
+        settings.setRequestBody(JSONObject.fromObject(Collections.singletonMap("name", "Test")).toString());
         assertReachableWithSettings(settings);
     }
     
@@ -401,9 +396,7 @@ public class DoActionFilterTest extends StaplerAbstractTest {
         settings.setRequestParameters(Collections.singletonList(
                 new NameValuePair(
                         "json",
-                        JSONObject.fromObject(new HashMap<String, Object>() {{
-                            put("name", "Test");
-                        }}).toString()
+                        JSONObject.fromObject(Collections.singletonMap("name", "Test")).toString()
                 )
         ));
         assertReachableWithSettings(settings);
diff --git a/test/src/test/java/jenkins/security/stapler/GetterMethodFilterTest.java b/test/src/test/java/jenkins/security/stapler/GetterMethodFilterTest.java
index fe98b31eb3..8ef9b3a49d 100644
--- a/test/src/test/java/jenkins/security/stapler/GetterMethodFilterTest.java
+++ b/test/src/test/java/jenkins/security/stapler/GetterMethodFilterTest.java
@@ -35,7 +35,6 @@ import org.jvnet.hudson.test.TestExtension;
 import java.awt.Point;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -172,9 +171,7 @@ public class GetterMethodFilterTest extends StaplerAbstractTest {
         }
         
         public Map<String, Renderable> getMap() {
-            return new HashMap<String, Renderable>() {{
-                put("a", new Renderable());
-            }};
+            return Collections.singletonMap("a", new Renderable());
         }
     }
     
diff --git a/test/src/test/java/jenkins/tasks/SimpleBuildWrapperTest.java b/test/src/test/java/jenkins/tasks/SimpleBuildWrapperTest.java
index 13a6f0c775..d75a2d0f97 100644
--- a/test/src/test/java/jenkins/tasks/SimpleBuildWrapperTest.java
+++ b/test/src/test/java/jenkins/tasks/SimpleBuildWrapperTest.java
@@ -167,7 +167,7 @@ public class SimpleBuildWrapperTest {
             private static final long serialVersionUID = 1;
             private int tearDownCount = 0;
             @Override public void tearDown(Run<?,?> build, FilePath workspace, Launcher launcher, TaskListener listener) throws IOException, InterruptedException {
-                listener.getLogger().println("ran DisposerImpl #" + (++tearDownCount));
+                listener.getLogger().println("ran DisposerImpl #" + ++tearDownCount);
             }
         }
         @TestExtension({ "disposer", "failedJobWithInterruptedDisposer" }) public static class DescriptorImpl extends BuildWrapperDescriptor {
diff --git a/test/src/test/java/lib/form/RepeatableTest.java b/test/src/test/java/lib/form/RepeatableTest.java
index a68bf025e7..ac836d13a4 100644
--- a/test/src/test/java/lib/form/RepeatableTest.java
+++ b/test/src/test/java/lib/form/RepeatableTest.java
@@ -99,8 +99,6 @@ public class RepeatableTest {
 
     /**
      * Test count of buttons in form
-     *
-     * @throws Exception
      */
     @Test
     public void testSimpleCheckNumberOfButtons() throws Exception {
@@ -118,8 +116,6 @@ public class RepeatableTest {
     
     /**
      * Test count of buttons in form
-     *
-     * @throws Exception
      */
     @Test
     public void testSimpleCheckNumberOfButtonsEnabledTopButton() throws Exception {