package com.example.core.mydemo.TypeAdapter;

import com.google.gson.FieldNamingStrategy;

import com.google.gson.Gson;

import com.google.gson.GsonBuilder;

import com.google.gson.annotations.SerializedName;

import java.lang.reflect.Field;

/**

 * 打印输出结果：

 jsonStr={"Result":null,"id":1,"data":null}

 bean=result:null id:1 data:null

 bean2=result:-1 id:1 data:null

 jsonStr2={"Result":-1,"id":1,"DATA":"Empty"}

 */

public class UserBean {

    @SerializedName("Result")

    public Integer result;

    public Long id;

    public String data;

    @Override

    public String toString() {

        return "result:"+result+" id:"+id+" data:"+data;

    }

    public static void main(String[] args) {

//        Gson gson = new Gson();

        //serializeNulls输出null

        Gson gson = new GsonBuilder().serializeNulls().create();

        UserBean userBean = new UserBean();

        userBean.setId(1);

//        userBean.setData(null);

//        userBean.setResult(null);

        String jsonStr = gson.toJson(userBean);

        System.out.println("jsonStr=" + jsonStr);

        UserBean bean = gson.fromJson(jsonStr,UserBean.class);

        System.out.println("bean=" + bean.toString());

        Gson gson2 = new GsonBuilder()

                .registerTypeAdapter(String.class,new StringAdapter())

                .registerTypeAdapter(Integer.class,new IntegerAdapter())

                .registerTypeAdapter(int.class,new IntegerAdapter())

                .setFieldNamingStrategy(new FirstLowerCaseStrategy())

                .create();

        UserBean bean2 = gson2.fromJson(jsonStr,UserBean.class);

        System.out.println("bean2=" + bean2.toString());

        System.out.println("jsonStr2=" + gson2.toJson(bean2));

    }

    public int getResult() {

        return result;

    }

    public void setResult(Integer result) {

        this.result = result;

    }

    public long getId() {

        return id;

    }

    public void setId(long id) {

        this.id = id;

    }

    public String getData() {

        return data;

    }

    public void setData(String data) {

        this.data = data;

    }

    public static class FirstLowerCaseStrategy implements FieldNamingStrategy {

        @Override

        public String translateName(Field f) {

//            System.out.println("name=" + f.getName());

            if("data".equalsIgnoreCase(f.getName())){

//                return f.getName().toLowerCase();

//                System.out.println("upper=" + f.getName().toUpperCase());

                return f.getName().toUpperCase();

            }else{

                return f.getName();

            }

        }

    }

}