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Custom extensions can depend on Java libraries other than com.parasoft.api.jar. For example, assume that you want your extension to use an open-source Java library. In order for SOAtest or Virtualize to successfully load such an extension, it must also locate the dependencies. To enable loading of that extension, you must list any jars used by your extension (excluding com.parasoft.api.jar) in a "ClassPath" header in your extension jar's MANIFEST.MF file. The Java tutorial provides details about how to set up a jar to depend on other jars (see http://docs.oracle.com/javase/tutorial/deployment/jar/downman.html).
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Custom extensions should not depend on internal, non-public jars. This includes any jar that is installed by SOAtest or Virtualize, but but is not in com.parasoft.api.jar. Any extensions that depend on such jars are unsupported and may not function in a later release.