原因：项目buildpath不对
解决方案：
右键项目-------build path--------configuration build path
的选择libraries找到JRE（这个时候你会发现这个jre前面有！或者是红X）选中remove掉重新为该项目选择一个JRE选中项目
project----clean
The import org.apache cannot be resolved
What IDE are you using? If it's eclipse, right click on the project -> Build Path -> Configure Build Path -> Libraries -> Add External Jar's
