右击有main方法的类

===> Run as

===> Run Configurations

===>双击java application

===> 单击有main方法的类

===>选中classpath选项卡

===> remove掉Bootstrap Entries下的android.jar

===> 然后点击advanced

===> Add Library

===>JRE System Library

===>next

===>最后finish

===>Run