public abstract interface ClassFileTransformer
  Comment     Returned-by     Constructor-argument     Method-argument     Field-type     Type-bound     Links  

An agent provides an implementation of this interface in order to transform class files. The transformation occurs before the class is defined by the JVM.

Note the term class file is used as defined in section 3.1 of The Java™ Virtual Machine Specification, to mean a sequence of bytes in class file format, whether or not they reside in a file.

See also:
java.lang.instrument.Instrumentation, java.lang.instrument.Instrumentation.addTransformer, java.lang.instrument.Instrumentation.removeTransformer

Since:  1.5