Unable to “Run on Server” a webapp from Eclipse

Question

When running my WebApp project from Eclipse most of times it run correctly. But if by mistake to stop server, I kill it in "Console" view on instead of "Stop" Server from "Servers" View. While running clean project I get this

java.lang.NullPointerException
at org.eclipse.wst.common.componentcore.internal.util.VirtualReferenceUtilities.getDefaultProjectArchiveName(VirtualReferenceUtilities.java:81)
at org.eclipse.jst.j2ee.componentcore.J2EEModuleVirtualComponent.getJavaClasspathReferences(J2EEModuleVirtualComponent.java:332)
at org.eclipse.jst.j2ee.componentcore.J2EEModuleVirtualComponent.getNonManifestRefs(J2EEModuleVirtualComponent.java:236)
at org.eclipse.jst.j2ee.componentcore.J2EEModuleVirtualComponent.getReferences(J2EEModuleVirtualComponent.java:160)
at org.eclipse.jst.j2ee.componentcore.J2EEModuleVirtualComponent.getReferences(J2EEModuleVirtualComponent.java:208)
at org.eclipse.jst.j2ee.componentcore.J2EEModuleVirtualComponent.getReferences(J2EEModuleVirtualComponent.java:201)
at org.eclipse.jst.common.internal.modulecore.SingleRootUtil.hasConsumableReferences(SingleRootUtil.java:217)
at org.eclipse.jst.common.internal.modulecore.SingleRootUtil.validateSingleRoot(SingleRootUtil.java:165)
at org.eclipse.jst.common.internal.modulecore.SingleRootUtil.isSingleRoot(SingleRootUtil.java:93)
at org.eclipse.jst.common.internal.modulecore.SingleRootExportParticipant.canOptimize(SingleRootExportParticipant.java:84)
at org.eclipse.wst.common.componentcore.internal.flat.FlatVirtualComponent.canOptimize(FlatVirtualComponent.java:136)
at org.eclipse.wst.common.componentcore.internal.flat.FlatVirtualComponent.cacheResources(FlatVirtualComponent.java:118)
at org.eclipse.wst.common.componentcore.internal.flat.FlatVirtualComponent.fetchResources(FlatVirtualComponent.java:101)
at org.eclipse.wst.web.internal.deployables.FlatComponentDeployable.members(FlatComponentDeployable.java:147)
at org.eclipse.wst.server.core.internal.ModulePublishInfo.hasDelta(ModulePublishInfo.java:418)
at org.eclipse.wst.server.core.internal.ServerPublishInfo.hasDelta(ServerPublishInfo.java:443)
at org.eclipse.wst.server.core.internal.Server.hasPublishedResourceDelta(Server.java:1539)
at org.eclipse.wst.server.core.internal.Server$ResourceChangeJob$1.visit(Server.java:214)
at org.eclipse.wst.server.core.internal.Server.visitModule(Server.java:2929)
at org.eclipse.wst.server.core.internal.Server.visit(Server.java:2913)
at org.eclipse.wst.server.core.internal.Server$ResourceChangeJob.run(Server.java:225)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

And while launching I get this

SEVERE: Error starting static Resources
java.lang.IllegalArgumentException: Document base D:\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\Webapp does not exist or is not a readable directory
    at org.apache.naming.resources.FileDirContext.setDocBase(FileDirContext.java:142)
    at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4319)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4488)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
    at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
    at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)

Please help recover from this.

Answer 1

I encountered the same issue and cleaning and recreating server does not help. But when I deployed another project, it was able to start successfully. After much comparison, I found differences in the .project files. So I copy the contents of the .project file of the working project into the one that has problem, add it back to the server and it works. Following is the contents of the .project file that works. Note that you need to change the name of the project accordingly:

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
<name>Project Name</name>
<comment></comment>
<projects>
</projects>
<buildSpec>
    <buildCommand>
        <name>org.eclipse.wst.jsdt.core.javascriptValidator</name>
        <arguments>
        </arguments>
    </buildCommand>
    <buildCommand>
        <name>org.eclipse.jdt.core.javabuilder</name>
        <arguments>
        </arguments>
    </buildCommand>
    <buildCommand>
        <name>org.eclipse.wst.common.project.facet.core.builder</name>
        <arguments>
        </arguments>
    </buildCommand>
    <buildCommand>
        <name>org.eclipse.wst.validation.validationbuilder</name>
        <arguments>
        </arguments>
    </buildCommand>
</buildSpec>
<natures>
    <nature>org.eclipse.jem.workbench.JavaEMFNature</nature>
    <nature>org.eclipse.wst.common.modulecore.ModuleCoreNature</nature>
    <nature>org.eclipse.wst.common.project.facet.core.nature</nature>
    <nature>org.eclipse.jdt.core.javanature</nature>
    <nature>org.eclipse.wst.jsdt.core.jsNature</nature>
</natures>

Answer 2

I suffered from this problem, but cause was different. Problem sprang from wrong server name([Project Name] != [Server Name]). I thought that i could figure out by recreate Server.

This Problem can solve by following below steps:

1. Remove Server : right click on [Severs] and remove server.
2. Delete Server : right click on [Project Explorer] and delete Server(you created).
3. Clean Project : menu[Project -> Clean]
4. Create Server : right click on [Severs] and new server.
5. Edit server.xml : Edit server.xml foor your web server.
6. Add Server : right click on [Severs] and remove server.

Answer 3

Just do maven -> Update project configuration and clean/build from your eclipse. Project will be loaded.

Answer 4

I have stopped using this method of running my webapp. I use mvn tomcat:run instead. Much easier. Though I don't know how to debug.

Answer 5

In my case it was enough to copy (from working project):

1. .settings
2. .classpath
3. .projects

Answer 6

This problem might be caused by your local project being out of sync with your code repository. I would suggest to refresh/synchronize your project.