OkHttp 请求

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什么是Okhttp

常见的网络请求

• get请求
• 普通的post form请求
  Content-Type：application/x-www-form-urlencoded
  • 支持问价上传的post form请求
    Content-Type：multipart/form-data;boundary=
  • post jsoon字符串请求
    常用用于APP与server
• 请求中携带自定义header信息

OkHttp的使用流程

• 创建请求：Request.Builder() Request对象
• 通过Request得到Call对象：client.newCall(Request) Call对象
• 执行Call
  • 同步 call.execute(
  • 异步 call.enqueue()
• 得到Response对象

封装参考

• https://www.jianshu.com/p/99b878783292
• https://zhuanlan.zhihu.com/p/627994145
• https://blog.csdn.net/weixin_45533623/article/details/104983842 很好的
• 请求参数 ：https://blog.csdn.net/qq_32583189/article/details/53785808?utm_medium=distribute.pc_relevant.none-task-blog-2~default~baidujs_baidulandingword~default-0-53785808-blog-134094372.235^v43^pc_blog_bottom_relevance_base3&spm=1001.2101.3001.4242.1&utm_relevant_index=3
• OKhttp FormBody和RequestBody的不同 https://blog.csdn.net/EUEHEUEN/article/details/86359852

下面是一个封装好的okhttp 类

package com.example.okhttpdemo02;

import okhttp3.Headers;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public class OKHttpUtil {
    private static  final OkHttpClient client = new OkHttpClient();

    //get 同步请求
    public static String getSync(String url) throws Exception{
        Request request = new Request.Builder().url(url).build();
        try (Response response = client.newCall(request).execute()) {
            return response.body().string();
        }
    }
    //post 同步
    public static String post(String url, String json) throws Exception {
        RequestBody body = RequestBody.create(json, okhttp3.MediaType.get("application/json"));
        Request request = new Request.Builder().url(url).post(body).build();
        try (Response response = client.newCall(request).execute()) {
            return response.body().string();
        }
    }

    //get  异步请求
    public static void getAsync(String url, Headers headers, okhttp3.Callback callback) {
        Request request = null;
        if(headers!=null){
            request = new Request.Builder().headers(headers).url(url).build();
        }else{
            request = new Request.Builder().url(url).build();
        }
        client.newCall(request).enqueue(callback);
    }

    //post 异步
    public static void postAsync(String url, String json,  Headers headers,okhttp3.Callback callback) {
        RequestBody body = RequestBody.create(json, okhttp3.MediaType.get("application/json"));
        Request request=null;
        if(headers !=null){
            request = new Request.Builder().url(url).headers(headers).post(body).build();
        }else{
            request = new Request.Builder().url(url).post(body).build();
        }
        client.newCall(request).enqueue(callback);
    }
}

  package com.example.okhttpdemo325;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;

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

public class MainActivity extends AppCompatActivity {
    private OkHttpClient okHttpClient;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        okHttpClient =new OkHttpClient();

        //get请求
//        new Thread(new Runnable() {
//            @Override
//            public void run() {
//                String urlStr="https://postman-echo.com/get?aaa=123&bbb=456";
//                Request request = new Request.Builder().url(urlStr).build();
//                Call call = okHttpClient.newCall(request);
//                try {
//                    Response response = call.execute();
//                    JSONObject jsonObject = new JSONObject(response.body().string());
//                    Log.e("OUT",jsonObject.optJSONObject("args").optString("aaa"));
//
//                } catch (Exception e) {
//                    e.printStackTrace();
//                }
//            }
//        }).start();

        //post请求  发送 json数据   MediaType.parse("application/json")
        new Thread(new Runnable() {
            @Override
            public void run() {
                String urlStr="https://postman-echo.com/post";
                JSONObject jsonObject =new JSONObject();
                try {
                    jsonObject.put("uname1","jack1");
                    jsonObject.put("uname2","jack2");
                    jsonObject.put("uname3","jack3");
                    RequestBody body = RequestBody.create(MediaType.parse("application/json"), jsonObject.toString());
                    Request request = new Request.Builder().url(urlStr).post(body).build();
                    Call call = okHttpClient.newCall(request);
                    Response response = call.execute();
                    //JSONObject out = new JSONObject(response.body().string());
                    Log.e("OUT",response.body().string());

                } catch (Exception e) {
                    e.printStackTrace();
                }

            }
        }).start();

        //post请求  发送 form数据
//        new Thread(new Runnable() {
//            @Override
//            public void run() {
//                String urlStr="https://postman-echo.com/post";
//                try {
//                    FormBody.Builder builder = new FormBody.Builder();
//                    builder.add("name1","jacke1");
//                    builder.add("name2","jacke2");
//                    RequestBody body = builder.build();
//                    Request request = new Request.Builder().url(urlStr).post(body).build();
//                    Call call = okHttpClient.newCall(request);
//                    Response response = call.execute();
//                    //JSONObject out = new JSONObject(response.body().string());
//                    Log.e("OUT",response.body().string());
//
//                } catch (Exception e) {
//                    e.printStackTrace();
//                }
//
//
//            }
//        }).start();

    }
}

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