java的反射实现：
判断发生了修改操作，判断两个对象是否发生属性值的变更，判断两个List集合内对象的属性值是否发生变更
今日份代码：
package com.sxd.streamTest; import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.serializer.SerializerFeature; import java.lang.reflect.Field; import java.util.*; /** * @ClassName Test * @Description 判断发生了修改操作，判断两个对象是否发生属性值的变更，判断两个List集合内对象的属性值是否发生变更 * @Author sxd * @Date 2020/02/14 10:07 * @Version 1.0 */ public class Test { //忽略的属性 List<String> ignoreFields = Arrays.asList("yn","id"); /** * 测试的入口方法，实例化几个对象 */ @org.junit.Test public void test(){ Date modifyTime = new Date(); Date modifyTime2 = new Date(); List<Long> list1 = new ArrayList<>(); list1.add(1L); list1.add(2L); List<Long> list2 = new ArrayList<>(); list1.add(1L); Student student1 = new Student(); student1.setAge(1); student1.setName("张三1"); student1.setModifyTime(modifyTime); student1.setStoreIdList(list1); student1.setYn(1); Student student2 = new Student(); student2.setAge(1); student2.setName("张三1"); student2.setModifyTime(modifyTime2); student2.setStoreIdList(list2); student2.setYn(-1); Student student3 = new Student(); student3.setAge(3); student3.setName("张三3"); student3.setModifyTime(modifyTime); student3.setYn(1); Student student4 = new Student(); student4.setAge(4); student4.setName("张三4"); student4.setModifyTime(modifyTime2); student4.setYn(-1); Student student5 = new Student(); student5.setAge(4); student5.setName("张三4"); student5.setModifyTime(modifyTime2); student5.setYn(11); List<Student> sList1 = Arrays.asList(student2,student1); List<Student> sList2 = Arrays.asList(student4,student3); System.out.println("List集合是否变更：" + listModifyContrast(sList2,sList1)); System.out.println("单个对象是否变更：" + objModifyContrast(student4,student5,false)); } /** * List数据变更对比 * 比较两个相同泛型的List集合中值是否相同 * @param newList * @param oldList * @return true有变更 false无变更 */ public Boolean listModifyContrast(List<? extends Object> newList, List<? extends Object> oldList){ boolean flag = false; if (newList != null && oldList != null){ if (newList.size() != oldList.size()){ flag = true; }else { int same = 0; for (Object newObj : newList) { for (Object oldObj : oldList) { if (isBaseType(newObj)){ if (newObj == oldObj){ same ++; } }else { if (!objModifyContrast(newObj,oldObj,false)){ same ++; } } } } if (same != newList.size()){ flag = true; } } }else { if (newList == null && oldList == null){ flag = false; }else { flag = true; } } return flag; } /** * 判断obj是否基本数据类型 * 这里Integer和int 都认定为基本类型 * @param obj * @return */ private boolean isBaseType(Object obj){ Class aClass = obj.getClass(); if (aClass == Integer.class || aClass ==Integer.TYPE || aClass == Byte.class || aClass == Byte.TYPE || aClass == Short.class || aClass == Short.TYPE || aClass == Character.class || aClass == Character.TYPE || aClass == Long.class || aClass == Long.TYPE || aClass == Double.class || aClass == Double.TYPE || aClass == Float.class || aClass == Float.TYPE || aClass == Boolean.class || aClass == Boolean.TYPE ){ return true; }else { return false; } } /** * 单个对象-属性修改对比 * 属性如果是集合类型，则要求泛型需要重写hashCode和equals方法 * @param newObj * @param oldObj * @param reset 是否重置属性 * @return true有变更 false无变更 */ public Boolean objModifyContrast(Object newObj,Object oldObj,boolean reset){ boolean flag = false; if (newObj != null && oldObj != null){ Map<String, Object> newMap = getReflexMap(newObj); Map<String, Object> oldMap = getReflexMap(oldObj); int diff = 0; for (String field : newMap.keySet()) { if (! ignoreFields.contains(field)){ Object newFieldValue = newMap.get(field); Object oldFieldValue = oldMap.get(field); if (newFieldValue != null && oldFieldValue != null){ if (newFieldValue.equals(oldFieldValue)){ if (reset){ newMap.put(field,null); oldMap.put(field,null); } }else { diff ++; } }else { if (!(newFieldValue == null && oldFieldValue == null)){ diff ++; } } } } if (diff > 0){ setReflexObj(newMap, newObj); setReflexObj(oldMap, oldObj); flag = true; }else { flag = false; } }else { if (newObj == null && oldObj == null){ flag = false; }else { flag = true; } } return flag; } /** * 获取对象的属性名 + 属性值 * @param obj * @return */ public Map<String,Object> getReflexMap(Object obj){ Map<String,Object> map = new HashMap<>(); Class<? extends Object> aClass = obj.getClass(); Field[] declaredFields = aClass.getDeclaredFields(); for (Field declaredField : declaredFields) { declaredField.setAccessible(true); String fieldName = declaredField.getName(); Object fieldValue = null; try { fieldValue = declaredField.get(obj); } catch (IllegalAccessException e) { e.printStackTrace(); } map.put(fieldName,fieldValue); } return map; } /** * 设置 对象的 属性名+属性值 * @param map * @return */ public Object setReflexObj(Map<String,Object> map,Object obj){ Set<String> fieldSet = map.keySet(); Class<? extends Object> aClass = obj.getClass(); for (String field : fieldSet) { try { Field declaredField = aClass.getDeclaredField(field); declaredField.setAccessible(true); declaredField.set(obj,map.get(field)); } catch (NoSuchFieldException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } } return obj; } }