同事讓我幫他找一個錯誤，他說明明寫的對的，怎麼老是報錯。其實，使用MyBaties在編寫sql配置文件時，都會遇到的一個小問題，問題雖小，對初學者可能都會碰到。
org.apache.ibatis.builder.IncompleteElementException: Could not find parameter map com.boco.fsmsys.amuse.dao.AmuseItemDao.amuseItem
at org.apache.ibatis.builder.MapperBuilderAssistant.setStatementParameterMap(MapperBuilderAssistant.java:326)
at org.apache.ibatis.builder.MapperBuilderAssistant.addMappedStatement(MapperBuilderAssistant.java:290)
at org.apache.ibatis.builder.xml.XMLStatementBuilder.parseStatementNode(XMLStatementBuilder.java:110)
at org.apache.ibatis.session.Configuration.buildAllStatements(Configuration.java:567)
at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:493)
at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:488)
at org.apache.ibatis.binding.MapperMethod.setupCommandType(MapperMethod.java:236)
at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:71)
at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:39)
at $Proxy9.find(Unknown Source)
at com.boco.fsmsys.amuse.service.impl.AmuseItemServiceImpl.find(AmuseItemServiceImpl.java:31)
at com.boco.fsmsys.amuse.service.impl.AmuseItemServiceImpl$$FastClassByCGLIB$$f42525b0.invoke(<generated>)
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:689)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:90)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:622)
at com.boco.fsmsys.amuse.service.impl.AmuseItemServiceImpl$$EnhancerByCGLIB$$b6a4972c.find(<generated>)
at com.boco.fsmsys.test.service.AmuseItemServiceTest.testFind(AmuseItemServiceTest.java:15)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
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.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
at org.junit.runners.BlockJUnit4Cla***unner.runChild(BlockJUnit4Cla***unner.java:73)
at org.junit.runners.BlockJUnit4Cla***unner.runChild(BlockJUnit4Cla***unner.java:46)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:180)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:41)
at org.junit.runners.ParentRunner$1.evaluate(ParentRunner.java:173)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
at org.junit.runners.ParentRunner.run(ParentRunner.java:220)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.IllegalArgumentException: Parameter Maps collection does not contain value for com.boco.fsmsys.amuse.dao.AmuseItemDao.amuseItem
at org.apache.ibatis.session.Configuration$StrictMap.get(Configuration.java:660)
at org.apache.ibatis.session.Configuration.getParameterMap(Configuration.java:442)
at org.apache.ibatis.builder.MapperBuilderAssistant.setStatementParameterMap(MapperBuilderAssistant.java:324)
... 45 more
從異常的提示發現是配置文件中，find這個方法的sql參數類型或者名稱寫錯了，但是你發現這個位置並沒有些寫錯。於是你很困惑，其實問題就在這個配置文件中，提示的也對，只是位置不對。mybaties中只要有任何一個地方報錯，都無法通過。最後發現是另個一個方法上將parameterType寫成了parameterMap了（
<select id="getClassByID" parameterMap="String" resultMap="cla***esultMap">
）。
再者之所以大家犯錯，有一個原因是在編寫配置文件時，會提示parameterMap ，但是這個在mybaties中已經不再用這個屬性了。所以大家寫配置文件時，要小心細心。