public static VM_Method getUniqueImplementation(VM_Method foo) {
public static synchronized VM_Method getUniqueImplementation(VM_Method foo) {
  public static VM_Method getUniqueImplementation(VM_Method foo) {    VM_Class I = foo.getDeclaringClass();    java.util.HashSet classes = allImplementors(I);    VM_Method firstMethod = null;    VM_Atom name = foo.getName();    VM_Atom desc = foo.getDescriptor();    for (java.util.Iterator i = classes.iterator(); i.hasNext(); ) {      VM_Class klass = (VM_Class)i.next();      VM_Method m = klass.findDeclaredMethod(name,desc);      if (firstMethod == null)         firstMethod = m;      if (m != firstMethod)        return null;    }    return firstMethod;  }