Replacing Java 7 with Java 6

Currently I am running java 7 on Windows 7

C:\>java -version
 java version "1.7.0"
 Java(TM) SE Runtime Environment (build 1.7.0-b147)
 Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode)
 

How can i replace it with Java 6 ?? What is the best way ??

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