java.lang.RuntimeException: Couldn't find that class Can't find resource rulesets/java/strings.xml. Make sure the resource is a valid file or URL or is on the CLASSPATH
   at net.sourceforge.pmd.RuleSetFactory.parseRuleSetNode(RuleSetFactory.java:229)
   at net.sourceforge.pmd.RuleSetFactory.createRuleSet(RuleSetFactory.java:157)
Caused: java.lang.reflect.InvocationTargetException
   at sun.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:0)
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:483)
   at pmd.config.ConfigUtils.getAllAvailableRules(ConfigUtils.java:154)
   at pmd.config.ConfigUtils.createRuleList(ConfigUtils.java:77)
   at pmd.config.PMDOptionsSettings.getRuleList(PMDOptionsSettings.java:166)
   at pmd.RunPMDAction.constructRuleSets(RunPMDAction.java:300)
   at pmd.RunPMDAction.performScan(RunPMDAction.java:160)
   at pmd.RunPMDAction.performAction(RunPMDAction.java:268)
   at org.openide.util.actions.NodeAction$DelegateAction$1.run(NodeAction.java:586)
   at org.openide.util.actions.ActionInvoker$1.run(ActionInvoker.java:95)
   at org.openide.util.actions.ActionInvoker$ActionRunnable.actionPerformed(ActionInvoker.java:162)
   at org.netbeans.core.ModuleActions.invokeAction(ModuleActions.java:109)
   at org.netbeans.modules.openide.actions.ActionsBridgeImpl.invokeAction(ActionsBridgeImpl.java:60)
   at org.openide.util.actions.ActionInvoker$ActionRunnable.doRun(ActionInvoker.java:153)
   at org.openide.util.actions.ActionInvoker$2.run(ActionInvoker.java:110)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1423)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)