Jetty8怎么配置DataSource？在jetty-maven-plugin中:配置报错 

求指导，求救谢谢~！
我用的是jetty 8.1.15.v20140411
pom.xml的配置如下：

jetty-env.xml配置如下：

web.xml的配置如下：
<resource-ref> <description>My DataSource Reference</description> <res-ref-name>jdbc/osworkflow</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Container</res-auth> </resource-ref>
但是當我mvn jetty:run的時候，卻出現如下錯誤：

java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        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 org.eclipse.jetty.webapp.IterativeDescriptorProcessor.visit(IterativeDescriptorProcessor.java:85)
        at org.eclipse.jetty.webapp.IterativeDescriptorProcessor.process(IterativeDescriptorProcessor.java:72)
        at org.eclipse.jetty.webapp.MetaData.resolve(MetaData.java:367)
        at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1240)
        at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:717)
        at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:494)
        at org.mortbay.jetty.plugin.JettyWebAppContext.doStart(JettyWebAppContext.java:298)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:172)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:95)
        at org.eclipse.jetty.server.Server.doStart(Server.java:282)
        at org.mortbay.jetty.plugin.JettyServer.doStart(JettyServer.java:65)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.mortbay.jetty.plugin.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:520)
        at org.mortbay.jetty.plugin.AbstractJettyMojo.execute(AbstractJettyMojo.java:365)
        at org.mortbay.jetty.plugin.JettyRunMojo.execute(JettyRunMojo.java:523)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:133)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:108)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:76)
        at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:116)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:361)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:155)
        at org.apache.maven.cli.MavenCli.execute(MavenCli.java:584)
        at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:213)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:157)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        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 org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by:
java.lang.IllegalStateException: Nothing to bind for name javax.sql.DataSource/default
        at org.eclipse.jetty.plus.webapp.PlusDescriptorProcessor.bindEntry(PlusDescriptorProcessor.java:895)
        at org.eclipse.jetty.plus.webapp.PlusDescriptorProcessor.bindResourceRef(PlusDescriptorProcessor.java:812)
        at org.eclipse.jetty.plus.webapp.PlusDescriptorProcessor.visitResourceRef(PlusDescriptorProcessor.java:252)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        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 org.eclipse.jetty.webapp.IterativeDescriptorProcessor.visit(IterativeDescriptorProcessor.java:85)
        at org.eclipse.jetty.webapp.IterativeDescriptorProcessor.process(IterativeDescriptorProcessor.java:72)
        at org.eclipse.jetty.webapp.MetaData.resolve(MetaData.java:367)
        at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1240)
        at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:717)
        at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:494)
        at org.mortbay.jetty.plugin.JettyWebAppContext.doStart(JettyWebAppContext.java:298)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:172)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:95)
        at org.eclipse.jetty.server.Server.doStart(Server.java:282)
        at org.mortbay.jetty.plugin.JettyServer.doStart(JettyServer.java:65)
        at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
        at org.mortbay.jetty.plugin.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:520)
        at org.mortbay.jetty.plugin.AbstractJettyMojo.execute(AbstractJettyMojo.java:365)
        at org.mortbay.jetty.plugin.JettyRunMojo.execute(JettyRunMojo.java:523)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:133)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:108)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:76)
        at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:116)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:361)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:155)
        at org.apache.maven.cli.MavenCli.execute(MavenCli.java:584)
        at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:213)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:157)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        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 org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)