初学Android网络封装

前言：模拟用户登录，从安卓发送请求到服务端校验，再从服务端返回给安卓校验结果

1.在AndroidManifest.xml文件中添加网络权限

 所放位置如图所示：

 2.添加依赖，在app模块下的build.gradle中添加okhttp和json的依赖

implementation group: 'com.squareup.okhttp3', name: 'okhttp', version: '4.9.0'
implementation 'com.alibaba:fastjson:1.2.10'

 添加位置如图所示，添加之后点击进行编译引入。

 3.封装一个实体类，用于接收请求后的响应信息。（响应，包括响应码code和响应体body）

public class ResponseBody {
    private String code;//响应码
    private Object result;//响应体
    public String getCode() {
        return code;
    }
    public void setCode(String code) {
        this.code = code;
    }
    public Object getResult() {
        return result;
    }
    public void setResult(Object result) {
        this.result = result;
    }
}

4.封装一个实体类（User）

public class User {
    private int id;
    private String username;
    private String password;
    private String phone;
    private String name;
    private String sex;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
}

 5.定义OkHttp工具，包括get，post两种请求方式

import androidx.annotation.NonNull;
import com.alibaba.fastjson.JSONObject;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import okhttp3.Cookie;
import okhttp3.CookieJar;
import okhttp3.FormBody;
import okhttp3.HttpUrl;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class OkHttpUtils {
    private static final String BASE_URL = "http://192.168.10.104:8080/"; //地址
    private static OkHttpClient client = new OkHttpClient();
    private static ResponseBody responseBody;
/**
因为OkHttp自带cookie效果，在构造方法中进行初始化，使其生效
*/
    public OkHttpUtils(){
        final Map> cookieStore=new HashMap<>();
        client=new OkHttpClient.Builder().cookieJar(new CookieJar() {
            @Override
            public void saveFromResponse(@NonNull HttpUrl httpUrl, @NonNull List list) {
                cookieStore.put(httpUrl.host(),list);
            }
            @NonNull
            @Override
            public List loadForRequest(@NonNull HttpUrl httpUrl) {
                List cookies=cookieStore.get(httpUrl.host());
                return cookies==null?new ArrayList<>():cookies;
            }
        }).build();
    }
    /**
     * get请求，这里没加线程控制，如果有需要可以加一下
     */
    public static ResponseBody get(String url) {
        Request request = new Request.Builder().url(getAbsoluteUrl(url)).build();
        Response response = null;
        try {
            response = client.newCall(request).execute();
            responseBody= dealResponse(response.body().string());
        } catch (IOException e) {
            e.printStackTrace();
        }
        return responseBody;
    }
    /**
     * post请求，参数是通过map键值对形式传递过来的
     */
    public static  ResponseBody  post(String url, Map value) {
        FormBody formBody=dealFormBody(value);
        Request request = new Request.Builder().url(getAbsoluteUrl(url)).post(formBody).build();
        Response response;
        try {
                response = client.newCall(request).execute();
            responseBody= dealResponse(response.body().string());
        } catch (IOException e) {
            e.printStackTrace();
        }
        return responseBody;
    }
/**
将请求返回结果封装到ResponseBody 
*/
    public static ResponseBody dealResponse(String result){
        ResponseBody responseBody=new ResponseBody();
            JSONObject json = JSONObject.parseObject(result);
            responseBody.setCode(json.get("code")+"");
            responseBody.setResult(json.get("data"));
            return responseBody;
    }
/*
处理请求参数
*/
    public static FormBody dealFormBody(Map maps){
        FormBody.Builder builder = new FormBody.Builder();
        Set keySet=maps.keySet();
        for(Iterator iterator = keySet.iterator(); iterator.hasNext();)
        {
            String key=iterator.next();
            builder.add(key, maps.get(key)+"");
        }
        return builder.build();
    }
/*
将url拼接起来，封装成完整url
*/
    private static String getAbsoluteUrl(String relativeUrl) {
        return BASE_URL + relativeUrl;
    }
}

6.定义好之后，测试访问

我在MainActivity中添加按钮进行的测试，具体界面就不一一介绍了，测试代码如下：

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import androidx.appcompat.app.AppCompatActivity;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import java.util.HashMap;
import java.util.Map;
import okhttp3.OkHttpClient;
public class MainActivity extends AppCompatActivity {
    private OkHttpClient okHttpClient;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button login= findViewById(R.id.login);
//为界面上的按钮设置监听事件，点击就会调用下面的test方法
        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                test();
            }
        });
    }
/*

*/
    public void test(){
        new Thread(()-> {
            String url="user/info/getUser";
            Map maps=new HashMap<>();
//将请求参数添加到map中
            maps.put("username","zhangsan");
            maps.put("password","123456");
            ResponseBody result=OkHttpUtils.post(url,maps);//传url参数和map
            System.out.println(result.getCode());
            User user= dealJsonToObject(result);
            System.out.println(result.getResult());
            System.out.println(user.getPhone());
        }).start();
    }
   //处理json到实体类
public User dealJsonToObject(ResponseBody result){
    JSONArray arr= (JSONArray) JSONArray.parse(result.getResult().toString());
    JSONObject jsonObject = arr.getJSONObject(0);
    User user = JSON.toJavaObject(jsonObject,User.class);
        return user;
}
}

7.服务器是由java编写

一个简易的网络请求封装，日后有更好的还会继续优化，希望可以帮助到你