java.lang.NoClassDefFoundError: org/apache/ibatis/type/TypeReference
1、错误描述
java.lang.NoClassDefFoundError: org/apache/ibatis/type/TypeReference at java.lang.ClassLoader.findBootstrapClass(Native Method) at java.lang.ClassLoader.findBootstrapClassOrNull(ClassLoader.java:1070) at java.lang.ClassLoader.loadClass(ClassLoader.java:414) at java.lang.ClassLoader.loadClass(ClassLoader.java:412) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:191) at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:91) at org.apache.ibatis.io.Resources.classForName(Resources.java:229) at org.apache.ibatis.builder.xml.XMLConfigBuilder.typeAliasesElement(XMLConfigBuilder.java:81) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:61) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:55) at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.parseMybatisConfiguration(ProcessEngineConfigurationImpl.java:927) at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.initMybatisConfiguration(ProcessEngineConfigurationImpl.java:910) at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.initSqlSessionFactory(ProcessEngineConfigurationImpl.java:891) at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.init(ProcessEngineConfigurationImpl.java:620) at org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl.buildProcessEngine(ProcessEngineConfigurationImpl.java:590) at org.activiti.engine.impl.test.TestHelper.getProcessEngine(TestHelper.java:229) at org.activiti.engine.test.ActivitiRule.initializeProcessEngine(ActivitiRule.java:237) at org.activiti.engine.test.ActivitiRule.starting(ActivitiRule.java:205) at org.activiti.engine.test.ActivitiRule.startingQuietly(ActivitiRule.java:171) at org.activiti.engine.test.ActivitiRule.access$000(ActivitiRule.java:86) at org.activiti.engine.test.ActivitiRule$1.evaluate(ActivitiRule.java:124) at org.junit.rules.RunRules.evaluate(RunRules.java:20) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) 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:675) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) java.lang.NullPointerException at org.activiti.designer.test.ProcessTestMyProcess.startProcess(ProcessTestMyProcess.java:28) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.activiti.engine.test.ActivitiRule$1.evaluate(ActivitiRule.java:126) at org.junit.rules.RunRules.evaluate(RunRules.java:20) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) 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:675) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) org.activiti.engine.ActivitiException: Programmatic error: could not instantiate org.activiti.designer.test.ProcessTestMyProcess at org.activiti.engine.test.ActivitiRule.finished(ActivitiRule.java:269) at org.activiti.engine.test.ActivitiRule.finishedQuietly(ActivitiRule.java:179) at org.activiti.engine.test.ActivitiRule.access$400(ActivitiRule.java:86) at org.activiti.engine.test.ActivitiRule$1.evaluate(ActivitiRule.java:135) at org.junit.rules.RunRules.evaluate(RunRules.java:20) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) 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:675) 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/activiti/designer/test/ProcessTestMyProcess at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:190) at org.activiti.engine.test.ActivitiRule.finished(ActivitiRule.java:266) ... 19 more
2、错误原因
由错误提示可知，缺少ibatis有关的jar包，但是查询资料发现是缺Mybatis有关的jar
3、解决办法
在pom.xml中添加
<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.1</version>
</dependency>