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                        /后端开发
                        
                            /Java
                        
                        /Hibernate初探之单表映射

请问为什么出错了错在哪

java.lang.NoClassDefFoundError: org/dom4j/DocumentException

at test.test.nint(test.java:25)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.lang.reflect.Method.invoke(Unknown Source)

at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)

at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)

at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)

at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:27)

at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)

at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)

at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)

at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)

at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)

at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)

at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)

at org.junit.runners.ParentRunner.run(ParentRunner.java:236)

at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)

at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

Caused by: java.lang.ClassNotFoundException: org.dom4j.DocumentException

at java.net.URLClassLoader.findClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

... 25 more

java.lang.NullPointerException

at test.test.destory(test.java:35)