question: @ Override public void visitFieldInsn ( int opcode , String owner , String name , String desc ) { if ( ! name . equals ( THIS$0 ) ) { String signInvoke = GGG_V ; Type fieldType = Type . getType ( desc ) ; if ( opcode == GETFIELD ) { mv . visitInsn ( DUP ) ; signInvoke = LGGG_V ; } if ( opcode == PUTFIELD ) { signInvoke = LGGG_V ; if ( fieldType . getSize ( ) == 1 ) stack . b1a1__b1a1b1 ( ) ; else if ( fieldType . getSize ( ) == 2 ) stack . b1a2__b1a2b1 ( ) ; else check ( false ) ; } stack . pushStrings ( owner , name , desc ) ; mv . visitMethodInsn ( INVOKESTATIC , VM_FQ , BYTECODE_NAME [ opcode ] , signInvoke ) ; } super . visitFieldInsn ( opcode , owner , name , desc ) ; }
target:  GETFIELD, PUTFIELD, GETSTATIC, PUTSTATIC http://java.sun.com/docs/books/jvms/second_edition/html/Instructions2. doc5.html#getfield http://java.sun.com/docs/books/jvms/second_edition/html /Instructions2.doc11.html#putfield