A ClassFileTransformer registered through an Instrumentation object is offered a chance to transform every class that is subsequently loaded or redefined. The final argument to transform( ) is a byte array that contains the raw bytes of the class file (or bytes returned by a previously invoked ClassFileTransformer ). If the TRansform( ) method wishes to transform the class, it should return the transformed bytes in a newly allocated array. The array passed to transform( ) should not be modified. If the transform( ) method does not wish to transform a given class, it should return null . public interface ClassFileTransformer { // Public Instance Methods byte[ ] transform (ClassLoader loader , String className , Class<?> classBeingRedefined , java.security.ProtectionDomain protectionDomain , byte[ ] classfileBuffer ) throws IllegalClassFormatException; } Passed ToInstrumentation.{addTransformer( ) , removeTransformer( )} |