code: @Override
      public void visitClassContext(ClassContext classContext) {
          try {
              if ((invocationHandlerClass != null) && classContext.getJavaClass().implementationOf(invocationHandlerClass)) {
                  return;
              }
              iConst0Looped = new BitSet();
              stack = new OpcodeStack();
              super.visitClassContext(classContext);
          } catch (ClassNotFoundException cnfe) {
              bugReporter.reportMissingClass(cnfe);
          } finally {
              iConst0Looped = null;
              stack = null;
          }
      }
docs: implements the visitor to create and clear the const0loop set
  
  @param classContext
  the context object of the currently parsed class