How to set classpath in java?

[prashantttt darekarrrr]

I want to know how to set classpath in java.I have installed SDK 1.5.0.So can someone guide me about it?

[Jesper de Jong]

You don't need to set the classpath, unless your Java program needs classes that are not in the current directory. If you're for example using classes in a third-party JAR file, then use "-cp" or "-classpath" options on the command line to include those classes in the classpath.

To compile:
javac -cp SomeJarFile.jar;. MyProgram.java

To run:
java -cp SomeJarFile.jar;. MyProgram

[Mandar Khire]

Jesper Young tells us very right answer, but i think this way is to write every time at compilation & running of program.But i think you can set class path which will be third party but you needed your certain program, in System properties.If you using WinXP then In
System properties-->Advanced-->Environment Variables
set variable as class path & Value as your desire jar file's lib path.
Then i think you should not write every time

To compile:
javac -cp SomeJarFile.jar;. MyProgram.java

To run:
java -cp SomeJarFile.jar;. MyProgram

.
Try this.

[Campbell Ritchie]

You don't need to set the classpath permanently; in fact if you do it will gradually become cluttered with unnecessary folder references.
You can repeat the line with the up and down arrows on command prompt or a shell. There is probably some way you can write something which will set the classpath for your session. I did a Google search and this came up first. Those instructions appear to apply to pre-XP Windows� but will probably work on XP too.