Map集合 & 实体类对象的相互转换

一、Map转实体类

1. fastjson工具类

导入依赖

<dependency>
   <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.54</version>
</dependency>

代码实现 

   Map<String, Object> authorMap = new HashMap<>();
        authorMap.put("id", 10L);
        authorMap.put("name", "蜡笔小新");
        authorMap.put("category", "分类");
        authorMap.put("score", 90);
        authorMap.put("intro", "简介");
        Book book = JSON.parseObject(JSON.toJSONString(authorMap), Book.class);
        System.out.println(book);

2. Jackson工具类

导入依赖

<!-- Jackson 核心库 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.12.5</version>
</dependency>

<!-- Jackson 数据绑定库 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.5</version>
</dependency>

代码实现

import com.fasterxml.jackson.databind.ObjectMapper;

Map<String, Object> personMap = new HashMap<>();
personMap.put("name", "John");
personMap.put("age", 20);

ObjectMapper mapper = new ObjectMapper();
Person person = mapper.convertValue(personMap, Person.class);

3. apache.commons.beanutils工具类

导入依赖

<dependency>
     <groupId>commons-beanutils</groupId>
     <artifactId>commons-beanutils</artifactId>
     <version>1.8.0</version>
     <scope>compile</scope>
</dependency>

代码实现

Map<String, Object> map = new HashMap<>();
map.put("id", 1);
map.put("name", "John");
map.put("age", 25);
Person person = new Person();
BeanUtils.populate(person, map);

二、实体类转Map

1. fastjson工具类

导入依赖

<dependency>
   <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.54</version>
</dependency>

代码实现

        Book book1 = new Book();
        book1.setId(1l);
        book1.setName("风间");
        book1.setCategory("分类");
        book1.setIntro("简介");
        book1.setScore(100);
        Map map = JSON.parseObject(JSON.toJSONString(book1), Map.class);
        System.out.println(map);

2. Jackson工具类

导入依赖

<!-- Jackson 核心库 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.12.5</version>
</dependency>

<!-- Jackson 数据绑定库 -->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.5</version>
</dependency>

代码实现

import com.fasterxml.jackson.databind.ObjectMapper;

Person person = new Person("John", 20);

ObjectMapper mapper = new ObjectMapper();
Map<String, Object> personMap = mapper.convertValue(person, Map.class);

3. apache.commons.beanutils工具类

导入依赖

<dependency>
     <groupId>commons-beanutils</groupId>
     <artifactId>commons-beanutils</artifactId>
     <version>1.8.0</version>
     <scope>compile</scope>
</dependency>

代码实现

Map<String, String> map = BeanUtils.describe(person);
map.remove("class");