Access restriction:The type JPEGCodec is not accessible due to restriction on required library C:\Program Files\Java\jre6\lib\rt.jar

解决方法： 
Project -> Properties -> libraries， 

先remove掉JRE System Library，然后再Add Library重新加入。

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在Eclipse中处理图片，需要引入两个包：
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
报错:
Access restriction: The type JPEGImageEncoder is not accessible due to restriction on required library C:\Java\jre1.6.0_07\lib\rt.jar

此时解决办法：
Eclipse 默认把这些受访问限制的API设成了ERROR。只要把Windows-Preferences-Java-Complicer- Errors/Warnings里面的Deprecated and restricted API中的Forbidden references(access rules)选为Warning就可以编译通过