Java 调用 Restful 接口

package com.chq.demo.test;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;


/**
 * 请求restful接口
 *
 * @author CHQ
 * @create 2019-04-03 10:33
 **/
public class HttpRestfulUtils {

    public static String doRestfulPost(String url, String json) {
        String result = "";
        try {
            URL targetUrl = new URL(url);
            HttpURLConnection httpConnection = (HttpURLConnection) targetUrl.openConnection();
            httpConnection.setDoOutput(true);
            httpConnection.setRequestMethod("POST");
            httpConnection.setRequestProperty("Content-Type", "application/json");
            OutputStream outputStream = httpConnection.getOutputStream();
            outputStream.write(json.getBytes());
            outputStream.flush();
            if (httpConnection.getResponseCode() != 200) {
                throw new RuntimeException("Failed : HTTP error code : "
                        + httpConnection.getResponseCode());
            }
            BufferedReader responseBuffer = new BufferedReader(new InputStreamReader((httpConnection.getInputStream())));
            String output;
            while ((output = responseBuffer.readLine()) != null) {
                result = output;
            }
            httpConnection.disconnect();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    public static String doRestfulGet(String url, String json) {
        String result = "";
        try {
            URL restServiceURL = new URL(url);
            HttpURLConnection httpConnection = (HttpURLConnection) restServiceURL.openConnection();
            httpConnection.setDoOutput(true);
            httpConnection.setRequestMethod("GET");
            httpConnection.setRequestProperty("Accept", "application/json");
            OutputStream outputStream = httpConnection.getOutputStream();
            outputStream.write(json.getBytes());
            outputStream.flush();
            if (httpConnection.getResponseCode() != 200) {
                throw new RuntimeException("HTTP GET Request Failed with Error code : "
                        + httpConnection.getResponseCode());
            }
            BufferedReader responseBuffer = new BufferedReader(new InputStreamReader(
                    (httpConnection.getInputStream())));
            String output;
            System.out.println("Output from Server:  \n");
            while ((output = responseBuffer.readLine()) != null) {
                System.out.println(output);
            }
            httpConnection.disconnect();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }


    public static void main(String[] args) {
        String url = "";
        String json = "{\"channel\":\"1003\",\"customerId\":\"12\"}";
        String result = doRestfulGet(url, json);
        System.out.println(result);
    }
}