mueclipse导入项目（或换了一个jdk版本）+　Implicit super constructor Object() is undefined for default constructor.

　Implicit super constructor Object() is undefined for default constructor. Must define an explicit constructor

解决方案：把java的类库加载进去，在工程上右键选择属性->Java Build Path的Libraries->Add Library选择JRE System Library->点击Next->选择Execution environment并选择版本或workspace default jre->点击Finish。

转自：https://www.cnblogs.com/kangyaping/p/7020814.html