Page History

public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
   // readRead instance fields
   this.name = (String)in.readObject();
   this.UID = in.readInt();
   //...
}

public synchronized void readExternal(ObjectInput in)
 throws IOException, ClassNotFoundException {
  if (!initialized) {
    // readRead instance fields
    this.name = (String)in.readObject();
    this.UID = in.readInt();
    //...  
    initialized = true;
  } else {
    throw new IllegalStateException();
  }
}