(1)配置clean up，然后执行source -> clean up

window -> preferences -> java -> code style -> clean up -> code organize -> formatter -> remove trailing whitespace

(2)将删除行尾空格配置在save actions里面，save文件的时候自动完成

window -> preferences -> java -> editor -> save actions -> additional actions -> configure -> code organizing -> formatter -> remove trailing whitespace

eclipse 删除尾部空格