public String getVirtualMethodShortName(int classIdx, int methodIdx) {
   Integer i = new Integer(classIdx);
   ClassHolder classHolder = classMap.get(i);
   if (classHolder == null) return null;
   MethodHolder methodHolder = classHolder.virtualMethods[methodIdx];
   return DexMethodIdsBlock.getMethodName(dexMethodIdsBlock.getMethod(methodHolder.methodId));
 }