Gson手动序列化POJO(工具类)

Posted 2020-08-11 字节

gson2.7版本

只是简单的工具类(练习所用):

package pojo;
import javax.xml.bind.annotation.XmlSeeAlso;

import com.google.gson.annotations.SerializedName;

public class User {
    public String name;
    public int age;
    @SerializedName(value="email_Address",alternate={"email"})
    public String emailAddress;
    public User() {
    }
    public User(String name, int age, String emailAddress) {
        super();
        this.name = name;
        this.age = age;
        this.emailAddress = emailAddress;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getEmailAddress() {
        return emailAddress;
    }
    public void setEmailAddress(String emailAddress) {
        this.emailAddress = emailAddress;
    }
    @Override
    public String toString() {
        return "User [name=" + name + ", age=" + age + ", emailAddress=" + emailAddress + "]";
    }
    
    
}

package utils;

import java.io.IOException;
import java.io.StringReader;
import java.lang.reflect.Field;

import com.google.gson.Gson;
import com.google.gson.stream.JsonReader;

import pojo.User;

/**
 * 处理json工具类
 * @Description:
 * @author zbs
 * @date 2016年9月30日 上午10:06:05
 */
public class JsonUtils {
    public static void main(String[] args) {
        String json="{\"name\":\"学学习\",\"age\":\"24\"}";
        User user = (User) getObjectFromJson(User.class, json);
        System.out.println(user);
    }
    /**
     * json-->pojo
     * @Description:序列化json
     * @param clazz
     * @param json
     * @return void 返回类型
     */
    @SuppressWarnings("all")
    public static  Object getObjectFromJson(Class clazz, String json) {
        JsonReader reader = new JsonReader(new StringReader(json));
        Field[] field = clazz.getDeclaredFields();
        Object obj = null;
        try {
            // 获取当前对象
            obj = clazz.newInstance();
            reader.beginObject();
            while (reader.hasNext()) {
                String name = reader.nextName();
                for (Field f : field) {
                    if (f.getName().equals(name)) {
                       if (f.getType() == int.class) {
                            f.setInt(obj, reader.nextInt());
                        }else if(f.getType() == Double.class){
                            f.setDouble(obj, reader.nextDouble());
                        }else if (f.getType() == Long.class) {
                            f.setLong(obj, reader.nextLong());
                        }else if (f.getType() == Boolean.class) {
                            f.setBoolean(obj, reader.nextBoolean());
                        }else{
                            f.set(obj, reader.nextString()); 
                        }
                    }
                }
            }
            reader.endObject();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return obj;
    }
}