[FELIX-4572] Web Console may cause NPE on refresh packages

• Type: Bug
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: webconsole-4.2.2
• Fix Version/s: webconsole-4.2.4
• Component/s: Web Console
• Assignee: Valentin Valchev
• Reporter: Valentin Valchev
• Created: 22/Jul/14 07:13
• Updated: 16/Mar/15 08:17
• Resolved: 22/Jul/14 07:17

Description

If you try to refresh packages on the webconsole or it's dependencies (like the fileupload) bundle, the following exception will be printed in the log file:

 [ERROR]8 : [HTTP] Problem while making answer to request /system/console/bundles/19 from client address 127.0.0.1:63063

java.lang.NullPointerException
        at org.osgi.util.tracker.ServiceTracker.<init>(ServiceTracker.java:207)
        at org.apache.felix.webconsole.SimpleWebConsolePlugin.getService(SimpleWebConsolePlugin.java:196)
        at org.apache.felix.webconsole.internal.core.BundlesServlet.getPackageAdmin(BundlesServlet.java:1403)
        at org.apache.felix.webconsole.internal.core.BundlesServlet.isFragmentBundle(BundlesServlet.java:715)
        at org.apache.felix.webconsole.internal.core.BundlesServlet.doPost(BundlesServlet.java:358)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:815)
        at org.apache.felix.webconsole.internal.servlet.OsgiManager.service(OsgiManager.java:493)
        at org.apache.felix.webconsole.internal.servlet.OsgiManager.service(OsgiManager.java:418)

The reason is that the refresh will cause the webconsole bundle to be restarted. Here is what happens:

1. doPost entered
2. sent package refresh
3. webconsole bundle is stopped
4. web console tries to access a service
5. NPE
6. doPost leaving

To prevent that, the bundle plugin should simply check if the bundleContext is null