interface Interface {} abstract class Parent {} class Child extends Parent implements Interface {} public aspect pr102212 { // illegal modifier combination not caught by ajc public abstract synchronized void Parent._abstract(); public synchronized void Child._abstract() {} // the following is legal - it's a default implementation.... public /* implicit abstract */ synchronized void Interface._interface() {} // use Child to make java complain: "illegal modifiers: 0x421" // (this corresponds to "public abstract synchronized") public static void main(String[] args) { new Child(); } }