Pulse "silently" fails if a plugin compiled against an incompatible jdk is installed. In my case I compiled the plugin against 1.6x and installed it into Pulse using a 1.5 jvm. This errors out with a bad class version error (see below for stack trace). The only way to see the problem was by viewing the logs - the plugin admin page showed the plugin as installed even though it wasn't available.

It would be much nicer if in this case the plugin admin page were to indicate that the plugin was "broken" with some information as to why.

INFO | jvm 1 | 2008/09/10 11:13:59 | Wed Sep 10 11:13:59 PDT 2008 - [Worker-1] Bundle tracker is not set
INFO | jvm 1 | 2008/09/10 11:13:59 | java.lang.UnsupportedClassVersionError: Bad version number in .class file
INFO | jvm 1 | 2008/09/10 11:13:59 | at java.lang.ClassLoader.defineClass1(Native Method)
INFO | jvm 1 | 2008/09/10 11:13:59 | at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.defineClass(DefaultClassLoader.java:161)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClass(ClasspathManager.java:501)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findClassImpl(ClasspathManager.java:471)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClassImpl(ClasspathManager.java:430)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:413)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:189)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleLoader.findLocalClass(BundleLoader.java:340)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleLoader.findClassInternal(BundleLoader.java:408)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:369)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:357)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:83)
INFO | jvm 1 | 2008/09/10 11:13:59 | at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleLoader.loadClass(BundleLoader.java:289)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.BundleHost.loadClass(BundleHost.java:227)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadClass(AbstractBundle.java:1269)
INFO | jvm 1 | 2008/09/10 11:13:59 | at com.zutubi.pulse.plugins.AbstractExtensionManager.loadClass(AbstractExtensionManager.java:88)
INFO | jvm 1 | 2008/09/10 11:13:59 | at com.zutubi.pulse.core.plugins.PostProcessorExtensionManager.handleConfigurationElement(PostProcessorExtensionManager.java:39)
INFO | jvm 1 | 2008/09/10 11:13:59 | at com.zutubi.pulse.plugins.AbstractExtensionManager.addExtension(AbstractExtensionManager.java:70)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.dynamichelpers.ExtensionTracker.applyAdd(ExtensionTracker.java:167)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.dynamichelpers.ExtensionTracker.notify(ExtensionTracker.java:159)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.dynamichelpers.ExtensionTracker.doAdd(ExtensionTracker.java:171)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.dynamichelpers.ExtensionTracker.registryChanged(ExtensionTracker.java:124)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.internal.registry.ExtensionRegistry$2.run(ExtensionRegistry.java:803)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.internal.registry.ExtensionRegistry.processChangeEvent(ExtensionRegistry.java:801)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.runtime.spi.RegistryStrategy.processChangeEvent(RegistryStrategy.java:246)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.internal.registry.osgi.ExtensionEventDispatcherJob.run(ExtensionEventDispatcherJob.java:50)
INFO | jvm 1 | 2008/09/10 11:13:59 | at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)