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Q) What is “CLASS PATH”?




A)
->CLASSPATH is an environmental variable used by java compiler and JVM to locate class files.(they may be user defined class file or library class file).

How to set this CLASSPATH :

->for J2SE platform, all library class file are located in the fallowing place
C:\program files\java jdk1.6.0\jre\rt.jar
->we need to place 2 locations in general in CLASS PATH environmental variable.
->Temporary: SET CLASS PATH = c:\program files\java\jdk1.6.0\jre\rt.jar
(Temporary setting the path on command prompt)
-> “.” Indicates current working directory that is recognized by JVM.
->Permanent: right click on my computer->properties->advanced->environmental variable->select CLASSPATH->click edit->go to beginning of the path put; and click ok.
->this is the permanent CLASSPATH setting
->whenever we set the temporary classpath we using dos permanent one it is exit then permanent classpath is used automatically when dos prompt is opened

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