@ Override public void visitClassContext ( ClassContext classContext ) { try { JavaClass cls = classContext . getJavaClass ( ) ; int major = cls . getMajor ( ) ; if ( major >= Const . MAJOR_1_5 ) { stack = new OpcodeStack ( ) ; super . visitClassContext ( classContext ) ; } } finally { stack = null ; } }
implements the visitor to check for class file version 1 . 5 or better