【异常】项目启动报UnsupportedClassVersionError

问题描述：

项目启动时，报UnsupportedClassVersionError异常

java.lang.UnsupportedClassVersionError: class in bundle[com.jiuqi.AssessmentOfStaff.ui] has unsupported class version: com.jiuqi.AssessmentOfStaff.ui.pageui2

at com.jiuqi.dna.core.impl.BundleStub.loadClass(BundleStub.java:137)

at com.jiuqi.dna.ui.wt.internal.UIEntryInfo.<init>(UIEntryFactory.java:65)

at com.jiuqi.dna.ui.wt.internal.UIEntryFactory.parseElement(UIEntryFactory.java:47)

at com.jiuqi.dna.ui.wt.internal.UIEntryFactory.parseElement(UIEntryFactory.java:1)

at com.jiuqi.dna.core.spi.publish.NamedFactory.parseElement(NamedFactory.java:1)

at com.jiuqi.dna.core.impl.PublishedElementGatherer.gatherElement(PublishedElementGatherer.java:51)

at com.jiuqi.dna.core.impl.PublishedElementGathererGroup.gatherElement(PublishedElementGathererGroup.java:33)

at com.jiuqi.dna.core.impl.BundleStub.gatherElement(BundleStub.java:66)

at com.jiuqi.dna.core.impl.Site.doInit(Site.java:107)

at com.jiuqi.dna.core.impl.Site.active(Site.java:200)

at com.jiuqi.dna.core.impl.ApplicationImpl.<init>(ApplicationImpl.java:368)

at com.jiuqi.dna.core.impl.ApplicationImpl.startApp(ApplicationImpl.java:684)

at com.jiuqi.dna.core.impl.ApplicationLauncherImpl.launch(ApplicationLauncherImpl.java:28)

at com.jiuqi.dna.core.impl.ApplicationLauncherImpl.launch(ApplicationLauncherImpl.java:1)

at com.jiuqi.dna.core.jetty.AppLauncherTracker.addingService(AppLauncherTracker.java:29)

at com.jiuqi.dna.core.jetty.AppLauncherTracker.addingService(AppLauncherTracker.java:1)

at org.osgi.util.tracker.ServiceTracker$Tracked.customizerAdding(ServiceTracker.java:932)

at org.osgi.util.tracker.ServiceTracker$Tracked.customizerAdding(ServiceTracker.java:1)

at org.osgi.util.tracker.AbstractTracked.trackAdding(AbstractTracked.java:256)

at org.osgi.util.tracker.AbstractTracked.trackInitial(AbstractTracked.java:183)

at org.osgi.util.tracker.ServiceTracker.open(ServiceTracker.java:317)

at org.osgi.util.tracker.ServiceTracker.open(ServiceTracker.java:261)

at com.jiuqi.dna.core.jetty.Activator.start(Activator.java:30)

at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:711)

at java.security.AccessController.doPrivileged(Native Method)

at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:702)

at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:683)

at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381)

at org.eclipse.osgi.framework.internal.core.AbstractBundle.resume(AbstractBundle.java:390)

at org.eclipse.osgi.framework.internal.core.Framework.resumeBundle(Framework.java:1177)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:559)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:544)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.incFWSL(StartLevelManager.java:457)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.doSetStartLevel(StartLevelManager.java:243)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:438)

at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:1)

at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)

at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:340)