sun.misc.BASE64Encoder找不到jar包的解決方法
1.右鍵項目-》屬性-》java bulid path-》jre System Library-》access rules-》resolution選擇accessible，下面填上** 點擊確定即可！！！
2.
在MyEclipse中編寫Java代碼時，用到了BASE64Decoder，import sun.misc.BASE64Decoder；可是Eclipse提示：
Access restriction: The type BASE64Decoder is not accessible due to restriction on required library C:\Program
files\java\jre6\lib\rt.jar
Access restriction : The constructor BASE64Decoder() is not accessible due to restriction on required library C:\Program files\java\jre6\lib\rt.jar
解決方案1（推薦）：
只需要在project build path中先移除JRE System Library，再添加庫JRE System Library，重新編譯后就一切正常了。
解決方案2：
Windows -> Preferences -> Java -> Compiler -> Errors/Warnings ->
Deprecated and trstricted API -> Forbidden reference (access rules): -> change to warning
Access restriction: The type BASE64Decoder is not accessible due to restriction on required library C:\Program
files\java\jre6\lib\rt.jar
Access restriction : The constructor BASE64Decoder() is not accessible due to restriction on required library C:\Program files\java\jre6\lib\rt.jar
解決方案1（推薦）：
只需要在project build path中先移除JRE System Library，再添加庫JRE System Library，重新編譯后就一切正常了。
解決方案2：
Windows -> Preferences -> Java -> Compiler -> Errors/Warnings ->
Deprecated and trstricted API -> Forbidden reference (access rules): -> change to warning