Android Studio运行报错，Cannot find System Java Compiler. Ensure that you have installed a JDK......

详细报错信息如下

Error:Execution failed for task ':app:compileDebugJavaWithJavac'.
> Cannot find System Java Compiler. Ensure that you have installed a JDK (not just a JRE) and configured your JAVA_HOME system variable to point to the according directory.

原因

  你要导入项目的gradle版本不对，要么过高要么过低，建议将gradle版本改为新建项目的gradle版本**

解决方案

  在找到project下面的build.gradle，修改gradle版本。如果不知道具体是哪个版本，可以直接复制新建项目的build.gradle版本。比如：将classpath ‘com.Android.tools.build:gradle:1.3.0’修改为classpath ‘com.android.tools.build:gradle:2.2.3’