IDEA+Maven+Mybatis 巨坑：org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.rao.mapper.UserMapper.findAll

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.rao.mapper.UserMapper.findAll

    at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:227)
    at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:49)
    at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:65)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:58)
    at com.sun.proxy.$Proxy8.findAll(Unknown Source)
    at com.rao.UserTest.func02(UserTest.java:37)
    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:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:160)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

上面是错误信息，就是说UserMapper.java和UserMapper.xml不匹配，查了几个小时的资料，各种方法都试了，感觉最好的一篇是下面这一篇，各位可以看一下：

https://blog.csdn.net/ppppfly/article/details/46847299

不过这也没有解决我的问题，不管怎么查看，包名，类名，方法名，方法参数类型，所有的东西都配置对了，还是报错，后来我又在resources下建了一个包，结果出现了下面这种情况：

 发现com.rao.mapper和com.rao.pojo居然没有合在一起，说明这两个包的前两级目录没有重合，然后我就到项目的目录下区看，发现包的名称如下图所示：

 com.rao.pojo居然成了1个包，不是3个包！！！！！！！！！！！！！

以前在IDEA里面建包时，直接创建com.rao.pojo是被创建成三个包的：com　　rao　　pojo，结果这里就成了一个包，叫做 ：com.rao.pojo

这样建立包结构java和xml肯定不会匹配，后来把包分步建立，就成功了，不报错了，这里真的巨坑！！！！！！！！