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order of jar files in classpath

ben oliver
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Joined: Mar 28, 2006
Posts: 375
I was following an instruction to add some .jar files into classpath. After that I found I could not compile properly, then I realized that I added all the jar files but not in the order it specified. So I changed the order of the jar files (still the same jar files) and it compiled fine.

Does the sequence of jar files you add to classpath matter and why ?
Rob Spoor

Joined: Oct 27, 2005
Posts: 20273

This probably has something to do with classes that are in more than 1 JAR file. The system class loader checks the JAR files / folders on the class path in order of declaration. If one JAR has version A of a class and another JAR has version B of that same class, then you will use version A if the first JAR is first and version B if the second is first.

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