diff --git a/core/src/main/java/hudson/PluginManager.java b/core/src/main/java/hudson/PluginManager.java
index 75e0873c43..56065582ae 100644
--- a/core/src/main/java/hudson/PluginManager.java
+++ b/core/src/main/java/hudson/PluginManager.java
@@ -1114,7 +1114,7 @@ public abstract class PluginManager extends AbstractModelObject implements OnMas
             
             try(final JarFile jarFile = jarURLConnection.getJarFile()) {
                 final JarEntry entry = (entryName != null && jarFile != null) ? jarFile.getJarEntry(entryName) : null;
-                if (entry != null && jarFile != null) {
+                if (entry != null) {
                     try(InputStream i = jarFile.getInputStream(entry)) {
                         byte[] manifestBytes = IOUtils.toByteArray(i);
                         in = new ByteArrayInputStream(manifestBytes);
diff --git a/core/src/main/java/hudson/model/StringParameterDefinition.java b/core/src/main/java/hudson/model/StringParameterDefinition.java
index 3573199a01..c992566558 100644
--- a/core/src/main/java/hudson/model/StringParameterDefinition.java
+++ b/core/src/main/java/hudson/model/StringParameterDefinition.java
@@ -132,7 +132,7 @@ public class StringParameterDefinition extends SimpleParameterDefinition {
 
     public ParameterValue createValue(String str) {
         StringParameterValue value = new StringParameterValue(getName(), str, getDescription());
-        if (isTrim() && value!=null) {
+        if (isTrim()) {
             value.doTrim();
         }
         return value;
diff --git a/core/src/main/java/hudson/util/ArgumentListBuilder.java b/core/src/main/java/hudson/util/ArgumentListBuilder.java
index 936a30a9c0..ac61eff9df 100644
--- a/core/src/main/java/hudson/util/ArgumentListBuilder.java
+++ b/core/src/main/java/hudson/util/ArgumentListBuilder.java
@@ -353,7 +353,7 @@ public class ArgumentListBuilder implements Serializable, Cloneable {
                 percent = (c == '%');
                 if (quoted) quotedArgs.append(c);
             }
-            if(i == 0 && quoted) quotedArgs.insert(0, '"'); else if (i == 0 && !quoted) quotedArgs.append('"');
+            if(i == 0 && quoted) quotedArgs.insert(0, '"'); else if (i == 0) quotedArgs.append('"');
             if (quoted) quotedArgs.append('"'); else quotedArgs.append(arg);
             
             windowsCommand.add(quotedArgs, mask.get(i));
diff --git a/core/src/main/java/hudson/util/SecretRewriter.java b/core/src/main/java/hudson/util/SecretRewriter.java
index 5a11e41847..7970f6cd70 100644
--- a/core/src/main/java/hudson/util/SecretRewriter.java
+++ b/core/src/main/java/hudson/util/SecretRewriter.java
@@ -197,7 +197,7 @@ public class SecretRewriter {
     }
 
     private static boolean isBase64(char ch) {
-        return 0<=ch && ch<128 && IS_BASE64[ch];
+        return ch<128 && IS_BASE64[ch];
     }
 
     private static boolean isBase64(String s) {
diff --git a/core/src/main/java/jenkins/widgets/HistoryPageFilter.java b/core/src/main/java/jenkins/widgets/HistoryPageFilter.java
index f152e6b05e..6026d11d56 100644
--- a/core/src/main/java/jenkins/widgets/HistoryPageFilter.java
+++ b/core/src/main/java/jenkins/widgets/HistoryPageFilter.java
@@ -210,7 +210,7 @@ public class HistoryPageFilter<T> {
                     }
                 }
             }
-        } else if (olderThan != null) {
+        } else {
             Iterator<ItemT> iter = items.iterator();
             while (iter.hasNext()) {
                 Object item = iter.next();