JDK7 CLASSPATH environment variable is not set yet

If that, after I manually put inside the jar package path CLASSPATH deleted , you can still compile and run the cmd inside , is not jdk7 CLASSPATH environment variable is not set up yet ?
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after 1.6 do not have to configure classpath , and only need to configure the path and java_home.
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1.7 do not have to configure the classpath default , as long as the configuration path java_home
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system default path so you have nothing to die deleted .
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default path is not already included in addition to all of the current directory jdk jar package ?
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I think it is such a system jdk jar package is % JAVA_HOME% \ jre \ lib \ rt.jar, do not specify the classpath in JDK7 before .
just JDK7 even " ; ." This does not need to specify the current directory .

However, when the introduction of other classes ( such as database-driven , etc. ) , or to specify the classpath .

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but when you are in a program which calls the package will be different pull .
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not need to configure
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understand.