java中部分方式实现Map转为自定义对象

自定义类

/**
 * @date 2023/12/19 11:20
 */
public class Person {
    private String name;
    private String sex;

    public Person() {
    }

    public Person(String name, String sex) {
        this.name = name;
        this.sex = sex;
    }

    public String getName() {
        return name;
    }

    public String getSex() {
        return sex;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

工具方法

import com.alibaba.fastjson.JSON;
import org.apache.commons.beanutils.BeanUtils;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.util.HashMap;
import java.util.Map;

/**
 * Map转为自定义对象
 *
 * @date 2023/12/21 14:17
 */
public class MapToObjUtils {

    /**
     * Map转为自定义对象
     * <p>
     * fastJson方式
     *
     * @param map
     * @param clazz
     * @return
     */
    public static <T> T mapToObj1(Map<String, Object> map, Class<T> clazz) {
        T object = null;
        try {
            object = JSON.parseObject(JSON.toJSONString(map), clazz);
        } catch (Exception e) {
            // 异常处理
        }
        return object;
    }

    /**
     * Map转为自定义对象
     * <p>
     * BeanUtils.populate方式
     *
     * @param map
     * @param person
     * @return
     */
    public static void mapToObj2(Map<String, Object> map, Person person) {
        try {
            BeanUtils.populate(person, map);
        } catch (IllegalAccessException | InvocationTargetException e) {
            // 异常处理
        }
    }

    /**
     * Map转为自定义对象
     * <p>
     * 反射方式
     *
     * @param map
     * @param clazz
     * @return
     */
    public static <T> T mapToObj3(Map<String, Object> map, Class<T> clazz) {
        try {
            T object = clazz.getDeclaredConstructor().newInstance();
            for (Map.Entry<String, Object> entry : map.entrySet()) {
                String fieldName = entry.getKey();
                Object fieldValue = entry.getValue();

                Field field = clazz.getDeclaredField(fieldName);
                field.setAccessible(true);
                field.set(object, fieldValue);
            }
            return object;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public static void main(String[] args) throws InvocationTargetException, IllegalAccessException, NoSuchMethodException {
        Map<String, Object> results = new HashMap<>();
        results.put("name", "小明");
        results.put("sex", "m");

        long start1 = System.currentTimeMillis();
        Person person1 = MapToObjUtils.mapToObj1(results, Person.class);
        long end1 = System.currentTimeMillis();
        long start2 = System.currentTimeMillis();
        Person person2 = new Person();
        MapToObjUtils.mapToObj2(results, person2);
        long end2 = System.currentTimeMillis();
        long start3 = System.currentTimeMillis();
        Person person3 = MapToObjUtils.mapToObj3(results, Person.class);
        long end3 = System.currentTimeMillis();
        System.out.println("Map转为自定义对象 fastJson方式耗时 " + (end1 - start1) + " 毫秒");
        System.out.println("Map转为自定义对象 BeanUtils.populate方式耗时 " + (end2 - start2) + " 毫秒");
        System.out.println("Map转为自定义对象 反射方式耗时 " + (end3 - start3) + " 毫秒");
    }
}

结果：