再用 junit 測試MyBatis時發現的錯誤：
| org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.apache.ibatis.reflection.ReflectionException: There is no getter for property named 'ItemsCustom' in 'class com.pojo.OrderDetailCustom' ### The error may exist in com/dao/OrderDetailMapper.xml ### The error may involve com.dao.OrderDetailMapper.searchOrderDetailByIdForResultMap ### The error occurred while handling results ### SQL: select o.id , o.items_num , o.orders_id , o.items_id , i.name , i.createtime from orderDetail o left join items i on o.items_id = i.id where o.id = ? ### Cause: org.apache.ibatis.reflection.ReflectionException: There is no getter for property named 'ItemsCustom' in 'class com.pojo.OrderDetailCustom' at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:83) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) at com.sun.proxy.$Proxy6.searchOrderDetailByIdForResultMap(Unknown Source) at com.test.TestUser.testSearchOrderDetailByIdForResultMap(TestUser.java:251) 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:498) 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.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26) 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: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: org.apache.ibatis.reflection.ReflectionException: There is no getter for property named 'ItemsCustom' in 'class com.pojo.OrderDetailCustom' at org.apache.ibatis.reflection.Reflector.getGetInvoker(Reflector.java:419) at org.apache.ibatis.reflection.MetaClass.getGetInvoker(MetaClass.java:164) at org.apache.ibatis.reflection.wrapper.BeanWrapper.getBeanProperty(BeanWrapper.java:162) at org.apache.ibatis.reflection.wrapper.BeanWrapper.get(BeanWrapper.java:49) at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:122) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.instantiateCollectionPropertyIfAppropriate(DefaultResultSetHandler.java:1129) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.applyNestedResultMappings(DefaultResultSetHandler.java:961) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.getRowValue(DefaultResultSetHandler.java:918) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValuesForNestedResultMap(DefaultResultSetHandler.java:881) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValues(DefaultResultSetHandler.java:328) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSet(DefaultResultSetHandler.java:303) at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSets(DefaultResultSetHandler.java:196) at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:64) at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:326) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ... 30 more |
從上面看錯誤是我們在pojo的類里面提供ItemsCustom的getter方法，但是在檢查該類是，確實已經提供了getter/setter方法，而且是ide生成的，那么問題出在哪呢，是junit報錯有偏差嗎？明顯不是的，我們有一個習慣在xml文件中使用類是都是類名，卻會疏忽在ItemsCustom這是一個引用類型，是當前類的一個自定義屬性，幾位就是說他是一個類型名，而我們在xml文件中也先入為主的寫了類名，代碼如下：
| <resultMap type="OrderDetailCustom" id="OTM"> <id column="id" property="id"/> <result column="items_num" property="items_num"/> <result column="orders_id" property="orders_id"/> <result column="items_id" property="items_id"/> <association property="ItemsCustom" javaType="ItemsCustom"> <result column="name" property="name"/> <result column="createtime" property="createtime"/> </association> </resultMap> |
而在property標簽中，我們要寫的是屬性，而這個屬性並不是這個類型，二十這個屬性名，我的是itemsCustom,將property標簽中的屬性名修改正確后即解決問題，代碼如下：
| <resultMap type="OrderDetailCustom" id="OTM"> <id column="id" property="id"/> <result column="items_num" property="items_num"/> <result column="orders_id" property="orders_id"/> <result column="items_id" property="items_id"/> <association property="itemsCustom" javaType="ItemsCustom"> <result column="name" property="name"/> <result column="createtime" property="createtime"/> </association> </resultMap> |
菜鳥在努力，希望我踩過的坑，能成為諸位bug兄的墊腳石！