Its always a tedious task to set path in java every time we restart our pc. Here is how to do that once so that u don't need to do this boring process again.
Steps :
1) Go to System Properties (Shortcut : Press Windows Key + Pause Break).
2) Now Go to "Advanced" Tab.
3) Click on Environment Variables... (See Image Below,Click to Enlarge ) .
4) Under "System Variables" scroll to "Path" and click "Edit".
5) Now what is present in that leave it as it is ( Don't delete any thing but just add after that) and add the following which is in quotes(without quotes) {As shown in image} :
";C:\Program Files\Java\jdk1.6.0\bin"
6)Note:Replace the above line with your path of jdk but add a semicolon first as i have done above
7)Click Ok,Again Ok,Again OK.
You are done.....