java原生发送http请求

根据技术选型总结常见的三种方式发送http请求，本问介绍jdk原生方式，其他两种如下链接

httpclient和okhttp

Springboot整合RestTemplate发送http请求

使用JDK原生提供的net包下的HttpURLConnection、URLConnection、Socket三个类都可实现，无需其他jar包

1、HttpURLConnection类实现

HttpURLConnection是URLConnection的子类，提供更多的方法，使用更方便。

比较原始的一种调用做法，这里把get请求和post请求都统一放在一个方法里面。

请求过程

1.  
   GET:
2.  
   1、创建远程连接
3.  
   2、设置连接方式（get、post、put。。。）
4.  
   3、设置连接超时时间
5.  
   4、设置响应读取时间
6.  
   5、发起请求
7.  
   6、获取请求数据
8.  
   7、关闭连接
9.  
    
10.  
    POST:
11.  
    1、创建远程连接
12.  
    2、设置连接方式（get、post、put。。。）
13.  
    3、设置连接超时时间
14.  
    4、设置响应读取时间
15.  
    5、当向远程服务器传送数据/写数据时，需要设置为true（setDoOutput）
16.  
    6、当前向远程服务读取数据时，设置为true，该参数可有可无（setDoInput）
17.  
    7、设置传入参数的格式:（setRequestProperty）
18.  
    8、设置鉴权信息：Authorization:（setRequestProperty）
19.  
    9、设置参数
20.  
    10、发起请求
21.  
    11、获取请求数据
22.  
    12、关闭连接

代码

1.  
   package com.riemann.springbootdemo.util.common.httpConnectionUtil;
2.  
    
3.  
   import org.springframework.lang.Nullable;
4.  
    
5.  
   import java.io.*;
6.  
   import java.net.HttpURLConnection;
7.  
   import java.net.MalformedURLException;
8.  
   import java.net.URL;
9.  
   import java.net.URLConnection;
10.  
     
11.  
     
12.  
    public class HttpURLConnectionUtil {
13.  
     
14.  
    /**
15.  
    * Http get请求
16.  
    * @param httpUrl 连接
17.  
    * @return 响应数据
18.  
    */
19.  
    public static String doGet(String httpUrl){
20.  
    //链接
21.  
    HttpURLConnection connection = null;
22.  
    InputStream is = null;
23.  
    BufferedReader br = null;
24.  
    StringBuffer result = new StringBuffer();
25.  
    try {
26.  
    //创建连接
27.  
    URL url = new URL(httpUrl);
28.  
    connection = (HttpURLConnection) url.openConnection();
29.  
    //设置请求方式
30.  
    connection.setRequestMethod("GET");
31.  
    //设置连接超时时间
32.  
    connection.setReadTimeout(15000);
33.  
    //开始连接
34.  
    connection.connect();
35.  
    //获取响应数据
36.  
    if (connection.getResponseCode() == 200) {
37.  
    //获取返回的数据
38.  
    is = connection.getInputStream();
39.  
    if (null != is) {
40.  
    br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
41.  
    String temp = null;
42.  
    while (null != (temp = br.readLine())) {
43.  
    result.append(temp);
44.  
    }
45.  
    }
46.  
    }
47.  
    } catch (IOException e) {
48.  
    e.printStackTrace();
49.  
    } finally {
50.  
    if (null != br) {
51.  
    try {
52.  
    br.close();
53.  
    } catch (IOException e) {
54.  
    e.printStackTrace();
55.  
    }
56.  
    }
57.  
    if (null != is) {
58.  
    try {
59.  
    is.close();
60.  
    } catch (IOException e) {
61.  
    e.printStackTrace();
62.  
    }
63.  
    }
64.  
    //关闭远程连接
65.  
    connection.disconnect();
66.  
    }
67.  
    return result.toString();
68.  
    }
69.  
     
70.  
    /**
71.  
    * Http post请求
72.  
    * @param httpUrl 连接
73.  
    * @param param 参数
74.  
    * @return
75.  
    */
76.  
    public static String doPost(String httpUrl, @Nullable String param) {
77.  
    StringBuffer result = new StringBuffer();
78.  
    //连接
79.  
    HttpURLConnection connection = null;
80.  
    OutputStream os = null;
81.  
    InputStream is = null;
82.  
    BufferedReader br = null;
83.  
    try {
84.  
    //创建连接对象
85.  
    URL url = new URL(httpUrl);
86.  
    //创建连接
87.  
    connection = (HttpURLConnection) url.openConnection();
88.  
    //设置请求方法
89.  
    connection.setRequestMethod("POST");
90.  
    //设置连接超时时间
91.  
    connection.setConnectTimeout(15000);
92.  
    //设置读取超时时间
93.  
    connection.setReadTimeout(15000);
94.  
    //DoOutput设置是否向httpUrlConnection输出，DoInput设置是否从httpUrlConnection读入，此外发送post请求必须设置这两个
95.  
    //设置是否可读取
96.  
    connection.setDoOutput(true);
97.  
    connection.setDoInput(true);
98.  
    //设置通用的请求属性
99.  
    connection.setRequestProperty("accept", "*/*");
100.  
     connection.setRequestProperty("connection", "Keep-Alive");
101.  
     connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
102.  
     connection.setRequestProperty("Content-Type", "application/json;charset=utf-8");
103.  
      
104.  
     //拼装参数
105.  
     if (null != param && param.equals("")) {
106.  
     //设置参数
107.  
     os = connection.getOutputStream();
108.  
     //拼装参数
109.  
     os.write(param.getBytes("UTF-8"));
110.  
     }
111.  
     //设置权限
112.  
     //设置请求头等
113.  
     //开启连接
114.  
     //connection.connect();
115.  
     //读取响应
116.  
     if (connection.getResponseCode() == 200) {
117.  
     is = connection.getInputStream();
118.  
     if (null != is) {
119.  
     br = new BufferedReader(new InputStreamReader(is, "GBK"));
120.  
     String temp = null;
121.  
     while (null != (temp = br.readLine())) {
122.  
     result.append(temp);
123.  
     result.append("\r\n");
124.  
     }
125.  
     }
126.  
     }
127.  
      
128.  
     } catch (MalformedURLException e) {
129.  
     e.printStackTrace();
130.  
     } catch (IOException e) {
131.  
     e.printStackTrace();
132.  
     } finally {
133.  
     //关闭连接
134.  
     if(br!=null){
135.  
     try {
136.  
     br.close();
137.  
     } catch (IOException e) {
138.  
     e.printStackTrace();
139.  
     }
140.  
     }
141.  
     if(os!=null){
142.  
     try {
143.  
     os.close();
144.  
     } catch (IOException e) {
145.  
     e.printStackTrace();
146.  
     }
147.  
     }
148.  
     if(is!=null){
149.  
     try {
150.  
     is.close();
151.  
     } catch (IOException e) {
152.  
     e.printStackTrace();
153.  
     }
154.  
     }
155.  
     //关闭连接
156.  
     connection.disconnect();
157.  
     }
158.  
     return result.toString();
159.  
     }
160.  
      
161.  
     public static void main(String[] args) {
162.  
     String message = doPost("https://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071", "");
163.  
     System.out.println(message);
164.  
     }
165.  
     }

2、URLConnection类实现

1.  
   package uRLConnection;
2.  
    
3.  
   import java.io.BufferedReader;
4.  
   import java.io.InputStream;
5.  
   import java.io.InputStreamReader;
6.  
   import java.net.HttpURLConnection;
7.  
   import java.net.URL;
8.  
   import java.net.URLConnection;
9.  
    
10.  
    public class URLConnectionHelper {
11.  
     
12.  
    public static String sendRequest(String urlParam) {
13.  
     
14.  
    URLConnection con = null;
15.  
     
16.  
    BufferedReader buffer = null;
17.  
    StringBuffer resultBuffer = null;
18.  
     
19.  
    try {
20.  
    URL url = new URL(urlParam);
21.  
    con = url.openConnection();
22.  
     
23.  
    //设置请求需要返回的数据类型和字符集类型
24.  
    con.setRequestProperty("Content-Type", "application/json;charset=GBK");
25.  
    //允许写出
26.  
    con.setDoOutput(true);
27.  
    //允许读入
28.  
    con.setDoInput(true);
29.  
    //不使用缓存
30.  
    con.setUseCaches(false);
31.  
    //得到响应流
32.  
    InputStream inputStream = con.getInputStream();
33.  
    //将响应流转换成字符串
34.  
    resultBuffer = new StringBuffer();
35.  
    String line;
36.  
    buffer = new BufferedReader(new InputStreamReader(inputStream, "GBK"));
37.  
    while ((line = buffer.readLine()) != null) {
38.  
    resultBuffer.append(line);
39.  
    }
40.  
    return resultBuffer.toString();
41.  
     
42.  
    }catch(Exception e) {
43.  
    e.printStackTrace();
44.  
    }
45.  
     
46.  
    return "";
47.  
    }
48.  
    public static void main(String[] args) {
49.  
    String url ="http://int.dpool.sina.com.cn/iplookup/iplookup.php?ip=120.79.75.96";
50.  
    System.out.println(sendRequest(url));
51.  
    }
52.  
    }

3、Socket类实现

1.  
   package socket;
2.  
   import java.io.BufferedInputStream;
3.  
   import java.io.BufferedReader;
4.  
   import java.io.BufferedWriter;
5.  
   import java.io.IOException;
6.  
   import java.io.InputStreamReader;
7.  
   import java.io.OutputStreamWriter;
8.  
   import java.net.Socket;
9.  
   import java.net.URLEncoder;
10.  
     
11.  
    import javax.net.ssl.SSLSocket;
12.  
    import javax.net.ssl.SSLSocketFactory;
13.  
     
14.  
    public class SocketForHttpTest {
15.  
     
16.  
    private int port;
17.  
    private String host;
18.  
    private Socket socket;
19.  
    private BufferedReader bufferedReader;
20.  
    private BufferedWriter bufferedWriter;
21.  
     
22.  
    public SocketForHttpTest(String host,int port) throws Exception{
23.  
     
24.  
    this.host = host;
25.  
    this.port = port;
26.  
     
27.  
    /**
28.  
    * http协议
29.  
    */
30.  
    // socket = new Socket(this.host, this.port);
31.  
     
32.  
    /**
33.  
    * https协议
34.  
    */
35.  
    socket = (SSLSocket)((SSLSocketFactory)SSLSocketFactory.getDefault()).createSocket(this.host, this.port);
36.  
     
37.  
     
38.  
    }
39.  
     
40.  
    public void sendGet() throws IOException{
41.  
    //String requestUrlPath = "/z69183787/article/details/17580325";
42.  
    String requestUrlPath = "/";
43.  
     
44.  
    OutputStreamWriter streamWriter = new OutputStreamWriter(socket.getOutputStream());
45.  
    bufferedWriter = new BufferedWriter(streamWriter);
46.  
    bufferedWriter.write("GET " requestUrlPath " HTTP/1.1\r\n");
47.  
    bufferedWriter.write("Host: " this.host "\r\n");
48.  
    bufferedWriter.write("\r\n");
49.  
    bufferedWriter.flush();
50.  
     
51.  
    BufferedInputStream streamReader = new BufferedInputStream(socket.getInputStream());
52.  
    bufferedReader = new BufferedReader(new InputStreamReader(streamReader, "utf-8"));
53.  
    String line = null;
54.  
    while((line = bufferedReader.readLine())!= null){
55.  
    System.out.println(line);
56.  
    }
57.  
    bufferedReader.close();
58.  
    bufferedWriter.close();
59.  
    socket.close();
60.  
     
61.  
    }
62.  
     
63.  
     
64.  
    public void sendPost() throws IOException{
65.  
    String path = "/";
66.  
    String data = URLEncoder.encode("name", "utf-8") "=" URLEncoder.encode("张三", "utf-8") "&"
67.  
    URLEncoder.encode("age", "utf-8") "=" URLEncoder.encode("32", "utf-8");
68.  
    // String data = "name=zhigang_jia";
69.  
    System.out.println(">>>>>>>>>>>>>>>>>>>>>" data);
70.  
    OutputStreamWriter streamWriter = new OutputStreamWriter(socket.getOutputStream(), "utf-8");
71.  
    bufferedWriter = new BufferedWriter(streamWriter);
72.  
    bufferedWriter.write("POST " path " HTTP/1.1\r\n");
73.  
    bufferedWriter.write("Host: " this.host "\r\n");
74.  
    bufferedWriter.write("Content-Length: " data.length() "\r\n");
75.  
    bufferedWriter.write("Content-Type: application/x-www-form-urlencoded\r\n");
76.  
    bufferedWriter.write("\r\n");
77.  
    bufferedWriter.write(data);
78.  
     
79.  
    bufferedWriter.write("\r\n");
80.  
    bufferedWriter.flush();
81.  
     
82.  
    BufferedInputStream streamReader = new BufferedInputStream(socket.getInputStream());
83.  
    bufferedReader = new BufferedReader(new InputStreamReader(streamReader, "utf-8"));
84.  
    String line = null;
85.  
    while((line = bufferedReader.readLine())!= null)
86.  
    {
87.  
    System.out.println(line);
88.  
    }
89.  
    bufferedReader.close();
90.  
    bufferedWriter.close();
91.  
    socket.close();
92.  
    }
93.  
     
94.  
    public static void main(String[] args) throws Exception {
95.  
    /**
96.  
    * http协议测试
97.  
    */
98.  
    //SocketForHttpTest forHttpTest = new SocketForHttpTest("www.百度.com", 80);
99.  
    /**
100.  
     * https协议测试
101.  
     */
102.  
     SocketForHttpTest forHttpTest = new SocketForHttpTest("www.百度.com", 443);
103.  
     try {
104.  
     forHttpTest.sendGet();
105.  
     // forHttpTest.sendPost();
106.  
     } catch (IOException e) {
107.  
      
108.  
     e.printStackTrace();
109.  
     }
110.  
     }
111.  
      
112.  
     }

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