java工具类-bean转map

工作常常遇到将java的Bean对象转化为Map，或者将Map转为Bean对象。

常见的手段

通过json工具，将Bean转json，再将json转Map

效率低

jdk的反射，获取类的属性，进行转化

比较麻烦，书写代码比较多

通过工具类BeanMap来完成

效率高，底层也是基于反射，不过做了些优化，比如缓存等手段 (推荐)

通过Apache的BeanUtils来完成

bean转化map是Map类型

循环转化1w次，对比下BeanMap和BeanUtils的耗时(毫秒)

方式bean转mapmap转beanBeanMap593364BeanUtils12542430

由上测试结果，我们可以看出BeanMap效率高，所以推荐使用BeanMap

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1.BeanMap方式

BeanMap是org.springframework.cglib.beans.BeanMap，在springcore中

1-1.工具类BeanMapTool

package com.iworkh.test.restassured.utils;

import org.springframework.cglib.beans.BeanMap;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

/**

* bean和map互转

*

* @author: iworkh-沐雨云楼

* @date: 2020-06-18

*/

public class BeanMapTool {

public static Map beanToMap(T bean) {

BeanMap beanMap = BeanMap.create(bean);

Map map = new HashMap<>();

beanMap.forEach((key, value) -> {

map.put(String.valueOf(key), value);

});

return map;

}

public static T mapToBean(Map map, Class clazz)

throws IllegalAccessException, InstantiationException {

T bean = clazz.newInstance();

BeanMap beanMap = BeanMap.create(bean);

beanMap.putAll(map);

return bean;

}

public static List> objectsToMaps(List objList) {

List> list = new ArrayList<>();

if (objList != null && objList.size() > 0) {

Map map = null;

T bean = null;

for (int i = 0, size = objList.size(); i < size; i++) {

bean = objList.get(i);

map = beanToMap(bean);

list.add(map);

}

}

return list;

}

public static List mapsToObjects(List> maps, Class clazz)

throws InstantiationException, IllegalAccessException {

List list = new ArrayList<>();

if (maps != null && maps.size() > 0) {

Map map = null;

for (int i = 0, size = maps.size(); i < size; i++) {

map = maps.get(i);

T bean = mapToBean(map, clazz);

list.add(bean);

}

}

return list;

}

}

1-2.调用

public class BeanMapToolTest {

@Test

public void testBeanToMap() {

String[] hobbies = {"football", "sing"};

UserVo user = new UserVo(1, "zhangsan", System.currentTimeMillis(), false, Arrays.asList(hobbies));

Map map = BeanMapTool.beanToMap(user);

System.out.println(map.get("name"));

}

@Test

public void testMapToBean() {

String[] hobbies = {"football", "sing"};

Map map = new HashMap<>();

map.put("id", 1);

map.put("name", "zhangsan");

map.put("birthday", System.currentTimeMillis());

map.put("vip", false);

map.put("hobbies", Arrays.asList(hobbies));

try {

UserVo userVo = BeanMapTool.mapToBean(map, UserVo.class);

System.out.println(userVo.getHobbies());

} catch (IllegalAccessException | InstantiationException e) {

e.printStackTrace();

}

}

}

2.BeanUtils方式

导入pom依赖

commons-beanutils

commons-beanutils

1.9.3

2-1.工具类BeanUtilsTool

package com.iworkh.test.restassured.utils;

import org.apache.commons.beanutils.BeanUtils;

import java.lang.reflect.InvocationTargetException;

import java.util.Map;

/**

* Apache BeanUtils工具类

*

* @author: iworkh-沐雨云楼

* @date: 2020-06-19

*/

public class BeanUtilsTool {

public static Map beanToMap(T bean)

throws IllegalAccessException, NoSuchMethodException, InvocationTargetException {

return BeanUtils.describe(bean);

}

public static T mapToBean(Map map, Class bean)

throws IllegalAccessException, InstantiationException, InvocationTargetException {

T t = bean.newInstance();

BeanUtils.populate(t, map);

return t;

}

}

2-2.调用

public class BeanUtilsToolTest {

@Test

public void testBeanToMap() {

String[] hobbies = {"football", "sing"};

UserVo user = new UserVo(1, "zhangsan", System.currentTimeMillis(), false, Arrays.asList(hobbies));

try {

Map map = BeanUtilsTool.beanToMap(user);

System.out.println(map.get("name"));

} catch (IllegalAccessException | NoSuchMethodException | InvocationTargetException e) {

e.printStackTrace();

}

}

@Test

public void testMapToBean() {

String[] hobbies = {"football", "sing"};

Map map = new HashMap<>();

map.put("id", 1);

map.put("name", "zhangsan");

map.put("birthday", System.currentTimeMillis());

map.put("vip", false);

map.put("hobbies", Arrays.asList(hobbies));

try {

UserVo userVo = BeanUtilsTool.mapToBean(map, UserVo.class);

System.out.println(userVo.getHobbies());

} catch (IllegalAccessException | InstantiationException | InvocationTargetException e) {

e.printStackTrace();

}

}

}

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