Here you can find the source of toHash(Object obj)
private static String toHash(Object obj)
//package com.java2s; /*/* w w w. j a v a 2s . c o m*/ * Copyright 2015-2017 the original author or authors. * * All rights reserved. This program and the accompanying materials are * made available under the terms of the Eclipse Public License v2.0 which * accompanies this distribution and is available at * * http://www.eclipse.org/legal/epl-v20.html */ public class Main { private static String toHash(Object obj) { return (obj == null ? "" : "@" + Integer.toHexString(System.identityHashCode(obj))); } }