接上文 除掉错误了 但是有个警告
Build path specifies execution environment J2SE-1.5. There are no JREs installed in the workspace that are strictly compatible with this environment.
project
-> properties
-> java build path : Libraries
Remove the “JRE System Library[J2SE 1.5]”
-> click “Add Library” button -> JRE System Library
-> select the new “Executin Environment” or Workspace default JRE