java记录一个对象改动前后哪些属性发生了变化

package com.haoyihang.test.invoke;

import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
public class CompareObj1 {

	public static void main(String[] args) {
		ObjectTest obj1=new ObjectTest("张三","1",null);
		ObjectTest obj2=new ObjectTest("李四","11",null);
		String[] ignoreArr= {"name","age","size"};
		String result=compareFields(obj1,obj2,ignoreArr);
		System.out.println(result);
	}
	
	 public static String compareFields(Object obj1, Object obj2, String[] ignoreArr) {
	        try {
	 
	            HashMap<String,Object> json = new HashMap<String,Object>();
	            List<String> ignoreList = null;
	            if (ignoreArr != null && ignoreArr.length > 0) {
	                ignoreList = Arrays.asList(ignoreArr);
	            }
	            if (obj1 == null && obj2 == null) {
	            }
	            if (obj1 == null) {
		            HashMap<String,Object> json1 = new HashMap<String,Object>();
	                Class clazz = obj2.getClass();
	                //获取object的属性描述
	                PropertyDescriptor[] pds = Introspector.getBeanInfo(clazz, Object.class).getPropertyDescriptors();
	                for (PropertyDescriptor pd : pds) {
	                    String name = pd.getName();
	                    if (ignoreList != null && ignoreList.contains(name)) {
	                        continue;
	                    }
	                    Method readMethod = pd.getReadMethod();//获取属性的get方法
	                    //在obj2上调用get方法等同于获得obj2的属性值
	                    Object o2 = readMethod.invoke(obj2);
	                    //不一致
	                    json1.put("变更后", o2);
	                    json.put(name, json1);
	                    continue;
	 
	                }
	                return json.toString();
	            } else if (obj2 == null) {
		            HashMap<String,Object> json1 = new HashMap<String,Object>();
	                Class clazz = obj1.getClass();
	                //获取object的属性描述
	                PropertyDescriptor[] pds = Introspector.getBeanInfo(null, Object.class).getPropertyDescriptors();
	                for (PropertyDescriptor pd : pds) {
	                    String name = pd.getName();
	                    if (ignoreList != null && ignoreList.contains(name)) {
	                        continue;
	                    }
	                    Method readMethod = pd.getReadMethod();//获取属性的get方法
	                    //在obj1上调用get方法等同于获得obj1的属性值
	                    Object o1 = readMethod.invoke(obj1);
	                    //不一致
	                    json1.put("变更前", o1);
	                    json.put(name, json1);
	                    continue;
	                }
	                return json.toString();
	            }
	            if (obj1.getClass() == obj2.getClass()) {
	                Class clazz = obj1.getClass();
	                //获取object的属性描述
	                Field[] fields = obj1.getClass().getDeclaredFields();//获得属性
	                for (Field field : fields) {
	                    PropertyDescriptor pd = new PropertyDescriptor(field.getName(),clazz);
	                    Method method = pd.getReadMethod();//获得get方法
	                    String name = pd.getName();
	                    //在obj1上调用get方法等同于获得obj1的属性值
	                    Object o1 = method.invoke(obj1);
	                    //在obj2上调用get方法等同于获得obj2的属性值
	                    Object o2 = method.invoke(obj2);
	                    if (o1 == null && o2 == null) {
	                        continue;
	                    }//比较时短路
	                    if (o1 == null || o2 == null || !o1.equals(o2)) {
	        	            HashMap<String,Object> json1 = new HashMap<String,Object>();
	                        json1.put("变更后", o2);
	                        json1.put("变更前", o1);
	                        json.put(name, json1);
	                    }
	                }
	                return json.toString();
	            }
	            return json.toString();
	        } catch (Exception e) {
	            e.printStackTrace();
	            return null;
	        }
	    }
}