Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/mail/util/LineInputStream

如果你用myEclipse進行開發的話，運行時可能會出現以下的錯誤:
Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/mail/util/LineInputStream
原因是jar包版本不統一,解決方法如下:

刪除Java EE 5 Libraries/javaee.jar/mail裏的包有東西.

具體方法如下:
用rar打開X:/Program Files/MyEclipse 6.0/myeclipse/eclipse/plugins/com.genuitec.eclipse.j2eedt.core_6.0.1.zmyeclipse601200710/data/libraryset/EE_5/javaee.jar
,然後刪除mail,一切就ok了.