mybatis 报错

java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for com.xiu.recommender.web.mapper.ProductHitsDataMapper.findProductId
 at org.apache.ibatis.session.Configuration$StrictMap.get(Configuration.java:594)
 at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:436)
 at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:428)
 at org.apache.ibatis.binding.MapperMethod.setupCommandType(MapperMethod.java:188)
 at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:51)
 at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:37)
 at $Proxy22.findProductId(Unknown Source)
 at com.xiu.recommender.web.service.ProductHitsDataService.getCounts(ProductHitsDataService.java:22)
 at com.xiu.recommender.web.service.ProductHitsDataServiceTest.testGetCounts(ProductHitsDataServiceTest.java:25)
 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.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
 at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83)
 at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
 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.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
 at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
 at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
 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)

 

 在unit里测试怎么也通不过，最后终于找到问题，原来是命名空间没写对，如果使用mapper，则

<mapper namespace="com.xiu.recommender.web.mapper.ProductHitsDataMapper">

空间中一定要写上Mapper的名称，否则就会报错。