1 package sample.duplicate; 2 3 import javassist.tools.reflect.*; 4 5 public class DuplicatedObject extends Metaobject { 6 private DuplicatedObject backup; 7 8 // if a base-level object is created, this metaobject creates 9 // a copy of the base-level object. 10 11 public DuplicatedObject(Object self, Object[] args) { 12 super(self, args); 13 ClassMetaobject clazz = getClassMetaobject(); 14 if (clazz.isInstance(args[0])) 15 backup = null; // self is a backup object. 16 else { 17 Object[] args2 = new Object[1]; 18 args2[0] = self; 19 try { 20 Metalevel m = (Metalevel)clazz.newInstance(args2); 21 backup = (DuplicatedObject)m._getMetaobject(); 22 } 23 catch (CannotCreateException e) { 24 backup = null; 25 } 26 } 27 } 28 29 public Object trapMethodcall(int identifier, Object[] args) 30 throws Throwable 31 { 32 Object obj = super.trapMethodcall(identifier, args); 33 if (backup != null) 34 backup.trapMethodcall(identifier, args); 35 36 return obj; 37 } 38 } 39
