diff --git a/changelog.html b/changelog.html
index c926905eb5..c121a698e2 100644
--- a/changelog.html
+++ b/changelog.html
@@ -60,7 +60,9 @@ Upcoming changes
- -
+
-
+ Proactively watch out for incomplete extensions to avoid cryptic NPE.
+ (issue 8866)
diff --git a/core/src/main/java/hudson/PluginManager.java b/core/src/main/java/hudson/PluginManager.java
index b4b843fc07..c275fa0e5c 100644
--- a/core/src/main/java/hudson/PluginManager.java
+++ b/core/src/main/java/hudson/PluginManager.java
@@ -455,6 +455,20 @@ public abstract class PluginManager extends AbstractModelObject {
return result;
}
+ /**
+ * Return the {@link PluginWrapper} that loaded the given class 'c'.
+ *
+ * @since 1.402.
+ */
+ public PluginWrapper whichPlugin(Class c) {
+ ClassLoader cl = c.getClassLoader();
+ for (PluginWrapper p : activePlugins) {
+ if (p.classLoader==cl)
+ return p;
+ }
+ return null;
+ }
+
/**
* Orderly terminates all the plugins.
*/
diff --git a/core/src/main/java/hudson/diagnosis/NullIdDescriptorMonitor.java b/core/src/main/java/hudson/diagnosis/NullIdDescriptorMonitor.java
new file mode 100644
index 0000000000..b54355f620
--- /dev/null
+++ b/core/src/main/java/hudson/diagnosis/NullIdDescriptorMonitor.java
@@ -0,0 +1,80 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2011, CloudBees, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson.diagnosis;
+
+import hudson.Extension;
+import hudson.PluginWrapper;
+import hudson.init.Initializer;
+import hudson.model.AdministrativeMonitor;
+import hudson.model.Descriptor;
+import hudson.model.Hudson;
+
+import java.text.MessageFormat;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.logging.Logger;
+
+import static hudson.init.InitMilestone.EXTENSIONS_AUGMENTED;
+
+/**
+ * Some old descriptors apparently has the getId() method that's used in different ways
+ * and that's causing errors like JENKINS-8866, so detect and report that.
+ *
+ * @author Kohsuke Kawaguchi
+ * @since 1.402
+ */
+@Extension
+public class NullIdDescriptorMonitor extends AdministrativeMonitor {
+
+ private final List problems = new ArrayList();
+
+ @Override
+ public boolean isActivated() {
+ return !problems.isEmpty();
+ }
+
+ public List getProblems() {
+ return Collections.unmodifiableList(problems);
+ }
+
+ private void verify() {
+ Hudson h = Hudson.getInstance();
+ for (Descriptor d : h.getExtensionList(Descriptor.class)) {
+ if (d.getId()==null) {
+ PluginWrapper p = h.getPluginManager().whichPlugin(d.getClass());
+ LOGGER.severe(MessageFormat.format("Descriptor {0} from plugin {1} with display name {2} has null ID",
+ d, p==null?"???":p.getLongName(), d.getDisplayName()));
+ problems.add(d);
+ }
+ }
+ }
+
+ @Initializer(after=EXTENSIONS_AUGMENTED)
+ public static void verifyId() {
+ AdministrativeMonitor.all().get(NullIdDescriptorMonitor.class).verify();
+ }
+
+ private static final Logger LOGGER = Logger.getLogger(NullIdDescriptorMonitor.class.getName());
+}
diff --git a/core/src/main/java/hudson/model/Descriptor.java b/core/src/main/java/hudson/model/Descriptor.java
index 5ad77d0862..183ba785a0 100644
--- a/core/src/main/java/hudson/model/Descriptor.java
+++ b/core/src/main/java/hudson/model/Descriptor.java
@@ -30,6 +30,8 @@ import hudson.BulkChange;
import hudson.Util;
import static hudson.Functions.jsStringEscape;
import hudson.diagnosis.OldDataMonitor;
+import hudson.init.InitMilestone;
+import hudson.init.Initializer;
import hudson.model.listeners.SaveableListener;
import hudson.util.ReflectionUtils;
import hudson.util.ReflectionUtils.Parameter;
@@ -41,12 +43,14 @@ import org.springframework.util.StringUtils;
import org.jvnet.tiger_types.Types;
import org.apache.commons.io.IOUtils;
+import static hudson.init.InitMilestone.EXTENSIONS_AUGMENTED;
import static javax.servlet.http.HttpServletResponse.SC_NOT_FOUND;
import javax.servlet.ServletException;
import javax.servlet.RequestDispatcher;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
+import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashMap;
diff --git a/core/src/main/java/hudson/model/Hudson.java b/core/src/main/java/hudson/model/Hudson.java
index 3975a337bf..54eb95f5a9 100644
--- a/core/src/main/java/hudson/model/Hudson.java
+++ b/core/src/main/java/hudson/model/Hudson.java
@@ -1682,7 +1682,7 @@ public final class Hudson extends Node implements ItemGroup, Stapl
public static final DescriptorImpl INSTANCE = new DescriptorImpl();
public String getDisplayName() {
- throw new UnsupportedOperationException();
+ return "";
}
@Override
diff --git a/core/src/main/resources/hudson/diagnosis/NullIdDescriptorMonitor/message.jelly b/core/src/main/resources/hudson/diagnosis/NullIdDescriptorMonitor/message.jelly
new file mode 100644
index 0000000000..3717859576
--- /dev/null
+++ b/core/src/main/resources/hudson/diagnosis/NullIdDescriptorMonitor/message.jelly
@@ -0,0 +1,36 @@
+
+
+
+
+ ${%blurb}
+
+
+ -
+ ${%problem(d, d.displayName, app.pluginManager.whichPlugin(d.getClass()))}
+
+
+
+