JSP——【报错】——The type java.io.ObjectInputStream cannot be resolved. It is indirectly referenced from r

出现The type java.io.ObjectInputStream cannot be resolved. It is indirectly referenced from required .class files的错误提示，如下图所示：

位置：package前

原因：jdk版本不一致

解决方法：

右击该项目工程->
Build Path->
Configure Build Path->
选中左侧的Java Build Path->
Add library->
选择JRE System Library
->在Alternate JRE按钮中下拉找到其自带的sun jdk 1.6->
点击finish完成