OkHttp在安卓中的使用

implementation 'com.squareup.okhttp3:okhttp:3.10.0'

<uses-permission android:name="android.permission.INTERNET"/>

package com.xxx.utils;

import android.os.Handler;
import android.os.Message;
import android.util.Log;
import java.io.IOException;
import java.util.Map;
import java.util.Set;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public class OkHttp3Utils<T> {

    public static final MediaType JSON = MediaType.parse("application/json;charset=utf-8");
    private static final MediaType URLENCODED=MediaType.parse("application/x-www-form-urlencoded;charset=utf-8");


    private OkHttpClient myOkHttpClient;



    //回调接口
    public interface AnsyCallback<T> {
        public void AnsyLoader(int what,T loder);
    }




    //get、post封装方法
    public void get(final String url,final AnsyCallback<T> ansyCallback){
        sendRequestWithOkHttp( url,null,ansyCallback,URLENCODED);
    }
    public void post(final String url,String body,final AnsyCallback<T> ansyCallback){
        sendRequestWithOkHttp( url,body,ansyCallback,URLENCODED);
    }





    /**
     * 将Map<String, String> 转换为 name=value&name=value 形式的字符串
     * @param map
     * @return
     */
     public static String map2NamVal(Map<String, String> map){
         StringBuilder str = new StringBuilder();
         Set<String> set = map.keySet();
         for (String key : set) {
             str.append(key).append("=").append(map.get(key)).append("&");
         }
         return str.toString().substring(0, str.lastIndexOf("&"));
     }



    /**
     * @param url 访问链接
     * @param body 请求参数
     * @param ansyCallback 回调接口
     * @param mime MIME类型
     */
    private void sendRequestWithOkHttp(final String url,String body,
                                final AnsyCallback<T> ansyCallback,MediaType mime){

        final Handler handler = new Handler() {
            @Override
            public void handleMessage(Message msg) {
                ansyCallback.AnsyLoader(msg.what,(T)msg.obj);
            }
        };

        myOkHttpClient = new OkHttpClient();
        Request.Builder requestBuilder = new Request.Builder().url(url);
        Request request;
        if (body != null) {
            RequestBody requestBody = RequestBody.create(mime,body);
            System.out.printf("******body*%s%s*******",mime,body);
            request = requestBuilder.post(requestBody).build();
        } else {
            request = requestBuilder.get().build();
        }
        Call mycall = myOkHttpClient.newCall(request);

//        发送异步请求
        mycall.enqueue(new Callback() {

            @Override
            public void onFailure(Call call, IOException e) {
                Message message = handler.obtainMessage(0,e.getStackTrace());
                handler.sendMessage(message);
            }

            @Override
            public void onResponse(Call call, Response response) throws IOException {
                if (!response.isSuccessful()) {
                    throw new IOException("请求失败: " + response.body().toString());
                }else {
                    if (null != response.cacheResponse()) {
                        String data = response.cacheResponse().toString();
                        handler.sendMessage(handler.obtainMessage(1, data));
                        System.out.println("****print****"+data);
                        Log.i("****Request****", "cache---" + data);
                    } else {
                        String data = response.body().string();
                        String str = response.networkResponse().toString();
                        Message message = handler.obtainMessage(1, data);
                        handler.sendMessage(message);
                        System.out.println("****print****"+data);
                        Log.i("****Request****", "network---" + str);
                    }
                }
            }
        });
    }

}

OkHttp3Utils<String> okHttp3 = new OkHttp3Utils<>();
Map<String, String> map=new HashMap<>();
map.put("username",id.getText().toString());
map.put("password", passwd.getText().toString());
map.put("isMax","false");
String databody=okHttp3.map2NamVal(map);

okHttp3.post(loginUrl,databody, new OkHttp3Utils.AnsyCallback<String>() {
    @Override
    public void AnsyLoader(int what,String loder) {
        try {
            JSONObject obj = new JSONObject(loder);
            if("1".equals(obj.get("status").toString())) {
                Intent intent = new Intent(StartActivity.this, Demo3ActivityWithFragment.class);
                startActivity(intent);
                Toast.makeText(getApplicationContext(), "登录成功", Toast.LENGTH_SHORT).show();
            }else{
                Toast.makeText(getApplicationContext(), "用户名或密码错误", Toast.LENGTH_SHORT).show();
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
});