原文：纯 java 实现 Http 资源读取工具，支持发送和接收数据，不依赖任何第三方 jar 包

源代码下载地址：http://www.zuidaima.com/share/1550463379950592.htm

纯 java 实现 Http 资源读取工具，支持发送和接收数据，不依赖任何第三方 jar 包

纯 Java 实现 Http 资源读取工具，支持发送和接收数据，不依赖任何第三方 jar 包

1. 抓取指定 URL 的资源，可以作为流，也可以作为 String

2. 向指定 URL POST 数据，模拟表单提交。

例如：你想模拟 XXX 自动登陆，然后再发表心情、签名之类的

3. 支持 URL 重定向

[java] view plain copy

print?

1. /* 
2.  *    Copyright 2012-2013 The Haohui Network Corporation 
3.  */  
4. package com.haohui.common.utils;  
5.   
6. /** 
7.  * @file HttpUtil.java 
8.  *  
9.  * @brief  
10.  * HttpUtil is a single class containing methods to conveniently perform HTTP  
11.  * requests. HttpUtil only uses regular java io and net functionality and does  
12.  * not depend on external libraries.  
13.  * The class contains methods to perform a get, post, put, and delete request, 
14.  * and supports posting forms. Optionally, one can provide headers. 
15.  * 
16.  * Example usage: 
17.  *  
18.  *     // get 
19.  *     String res = HttpUtil.get("http://www.zuidaima.com"); 
20.  *  
21.  *     // post 
22.  *     String res = HttpUtil.post("http://www.zuidaima.com/share/1550463379950592.htm", "This is the data"); 
23.  * 
24.  *     // post form 
25.  *     Map<String, String> params = new HashMap<String, String>(); 
26.  *     params.put("firstname", "Joe"); 
27.  *     params.put("lastname", "Smith"); 
28.  *     params.put("age", "28"); 
29.  *     String res = HttpUtil.postForm("http://site.com/newuser", params); 
30.  * 
31.  *     // append query parameters to url 
32.  *     String url = "http://mydatabase.com/users"; 
33.  *     Map<String, String> params = new HashMap<String, String>(); 
34.  *     params.put("orderby", "name"); 
35.  *     params.put("limit", "10"); 
36.  *     String fullUrl = HttpUtil.appendQueryParams(url, params); 
37.  *     // fullUrl = "http://mydatabase.com/user?orderby=name&limit=10" 
38.  * 
39.  * @license 
40.  * Licensed under the Apache License, Version 2.0 (the "License"); you may not 
41.  * use this file except in compliance with the License. You may obtain a copy  
42.  * of the License at 
43.  *  
44.  * http://www.apache.org/licenses/LICENSE-2.0 
45.  *  
46.  * Unless required by applicable law or agreed to in writing, software 
47.  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 
48.  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 
49.  * License for the specific language governing permissions and limitations under 
50.  * the License. 
51.  * 
52.  * Copyright (c) 2012 Almende B.V. 
53.  * 
54.  * @author  Jos de Jong, <[e-mail]> www.zuidaima.com 
55.  * @date      2012-05-14 
56.  */  
57.   
58. import java.io.IOException;  
59. import java.io.InputStream;  
60. import java.io.OutputStream;  
61. import java.net.HttpURLConnection;  
62. import java.net.URL;  
63. import java.net.URLDecoder;  
64. import java.net.URLEncoder;  
65. import java.util.HashMap;  
66. import java.util.Map;  
67.   
68. /** 
69.  * https://raw.github.com/wjosdejong/httputil/master/src/com/almende/util/HttpUtil.java 
70.  *  
71.  * @project baidamei 
72.  * @author cevencheng <[e-mail]> 
73.  * @create 2012-11-17 下午2:35:38 
74.  */  
75. public class HttpUtil {  
76.     /** 
77.      * Send a get request 
78.      * @param url 
79.      * @return response 
80.      * @throws IOException  
81.      */  
82.     static public String get(String url) throws IOException {  
83.         return get(url, null);  
84.     }  
85.   
86.     /** 
87.      * Send a get request 
88.      * @param url         Url as string 
89.      * @param headers     Optional map with headers 
90.      * @return response   Response as string 
91.      * @throws IOException  
92.      */  
93.     static public String get(String url,  
94.             Map<String, String> headers) throws IOException {  
95.         return fetch("GET", url, null, headers);  
96.     }  
97.   
98.     /** 
99.      * Send a post request 
100.      * @param url         Url as string 
101.      * @param body        Request body as string 
102.      * @param headers     Optional map with headers 
103.      * @return response   Response as string 
104.      * @throws IOException  
105.      */  
106.     static public String post(String url, String body,  
107.             Map<String, String> headers) throws IOException {  
108.         return fetch("POST", url, body, headers);  
109.     }  
110.   
111.     /** 
112.      * Send a post request 
113.      * @param url         Url as string 
114.      * @param body        Request body as string 
115.      * @return response   Response as string 
116.      * @throws IOException  
117.      */  
118.     static public String post(String url, String body) throws IOException {  
119.         return post(url, body, null);  
120.     }  
121.   
122.     /** 
123.      * Post a form with parameters 
124.      * @param url         Url as string 
125.      * @param params      map with parameters/values 
126.      * @return response   Response as string 
127.      * @throws IOException  
128.      */  
129.     static public String postForm(String url, Map<String, String> params)   
130.             throws IOException {  
131.         return postForm(url, params, null);  
132.     }  
133.   
134.     /** 
135.      * Post a form with parameters 
136.      * @param url         Url as string 
137.      * @param params      Map with parameters/values 
138.      * @param headers     Optional map with headers 
139.      * @return response   Response as string 
140.      * @throws IOException  
141.      */  
142.     static public String postForm(String url, Map<String, String> params,  
143.             Map<String, String> headers) throws IOException {  
144.         // set content type  
145.         if (headers == null) {  
146.             headers = new HashMap<String, String>();  
147.         }  
148.         headers.put("Content-Type", "application/x-www-form-urlencoded");  
149.   
150.         // parse parameters  
151.         String body = "";  
152.         if (params != null) {  
153.             boolean first = true;  
154.             for (String param : params.keySet()) {  
155.                 if (first) {  
156.                     first = false;  
157.                 }  
158.                 else {  
159.                     body += "&";  
160.                 }  
161.                 String value = params.get(param);  
162.                 body += URLEncoder.encode(param, "UTF-8") + "=";  
163.                 body += URLEncoder.encode(value, "UTF-8");  
164.             }  
165.         }  
166.   
167.         return post(url, body, headers);  
168.     }  
169.   
170.     /** 
171.      * Send a put request 
172.      * @param url         Url as string 
173.      * @param body        Request body as string 
174.      * @param headers     Optional map with headers 
175.      * @return response   Response as string 
176.      * @throws IOException  
177.      */  
178.     static public String put(String url, String body,  
179.             Map<String, String> headers) throws IOException {  
180.         return fetch("PUT", url, body, headers);  
181.     }  
182.   
183.     /** 
184.      * Send a put request 
185.      * @param url         Url as string 
186.      * @return response   Response as string 
187.      * @throws IOException  
188.      */  
189.     static public String put(String url, String body) throws IOException {  
190.         return put(url, body, null);  
191.     }  
192.       
193.     /** 
194.      * Send a delete request 
195.      * @param url         Url as string 
196.      * @param headers     Optional map with headers 
197.      * @return response   Response as string 
198.      * @throws IOException  
199.      */  
200.     static public String delete(String url,  
201.             Map<String, String> headers) throws IOException {  
202.         return fetch("DELETE", url, null, headers);  
203.     }  
204.       
205.     /** 
206.      * Send a delete request 
207.      * @param url         Url as string 
208.      * @return response   Response as string 
209.      * @throws IOException  
210.      */  
211.     static public String delete(String url) throws IOException {  
212.         return delete(url, null);  
213.     }  
214.       
215.     /** 
216.      * Append query parameters to given url 
217.      * @param url         Url as string 
218.      * @param params      Map with query parameters 
219.      * @return url        Url with query parameters appended 
220.      * @throws IOException  
221.      */  
222.     static public String appendQueryParams(String url,   
223.             Map<String, String> params) throws IOException {  
224.         String fullUrl = new String(url);  
225.           
226.         if (params != null) {  
227.             boolean first = (fullUrl.indexOf('?') == -1);  
228.             for (String param : params.keySet()) {  
229.                 if (first) {  
230.                     fullUrl += '?';  
231.                     first = false;  
232.                 }  
233.                 else {  
234.                     fullUrl += '&';  
235.                 }  
236.                 String value = params.get(param);  
237.                 fullUrl += URLEncoder.encode(param, "UTF-8") + '=';  
238.                 fullUrl += URLEncoder.encode(value, "UTF-8");  
239.             }  
240.         }  
241.           
242.         return fullUrl;  
243.     }  
244.       
245.     /** 
246.      * Retrieve the query parameters from given url 
247.      * @param url         Url containing query parameters 
248.      * @return params     Map with query parameters 
249.      * @throws IOException  
250.      */  
251.     static public Map<String, String> getQueryParams(String url)   
252.             throws IOException {  
253.         Map<String, String> params = new HashMap<String, String>();  
254.       
255.         int start = url.indexOf('?');  
256.         while (start != -1) {  
257.             // read parameter name  
258.             int equals = url.indexOf('=', start);  
259.             String param = "";  
260.             if (equals != -1) {  
261.                 param = url.substring(start + 1, equals);  
262.             }  
263.             else {  
264.                 param = url.substring(start + 1);  
265.             }  
266.               
267.             // read parameter value  
268.             String value = "";  
269.             if (equals != -1) {  
270.                 start = url.indexOf('&', equals);  
271.                 if (start != -1) {  
272.                     value = url.substring(equals + 1, start);  
273.                 }  
274.                 else {  
275.                     value = url.substring(equals + 1);  
276.                 }  
277.             }  
278.               
279.             params.put(URLDecoder.decode(param, "UTF-8"),   
280.                 URLDecoder.decode(value, "UTF-8"));  
281.         }  
282.           
283.         return params;  
284.     }  
285.   
286.     /** 
287.      * Returns the url without query parameters 
288.      * @param url         Url containing query parameters 
289.      * @return url        Url without query parameters 
290.      * @throws IOException  
291.      */  
292.     static public String removeQueryParams(String url)   
293.             throws IOException {  
294.         int q = url.indexOf('?');  
295.         if (q != -1) {  
296.             return url.substring(0, q);  
297.         }  
298.         else {  
299.             return url;  
300.         }  
301.     }  
302.       
303.     /** 
304.      * Send a request 
305.      * @param method      HTTP method, for example "GET" or "POST" 
306.      * @param url         Url as string 
307.      * @param body        Request body as string 
308.      * @param headers     Optional map with headers 
309.      * @return response   Response as string 
310.      * @throws IOException  
311.      */  
312.     static public String fetch(String method, String url, String body,  
313.             Map<String, String> headers) throws IOException {  
314.         // connection  
315.         URL u = new URL(url);  
316.         HttpURLConnection conn = (HttpURLConnection)u.openConnection();  
317.         conn.setConnectTimeout(10000);  
318.         conn.setReadTimeout(10000);  
319.   
320.         // method  
321.         if (method != null) {  
322.             conn.setRequestMethod(method);  
323.         }  
324.   
325.         // headers  
326.         if (headers != null) {  
327.             for(String key : headers.keySet()) {  
328.                 conn.addRequestProperty(key, headers.get(key));  
329.             }  
330.         }  
331.   
332.         // body  
333.         if (body != null) {  
334.             conn.setDoOutput(true);  
335.             OutputStream os = conn.getOutputStream();  
336.             os.write(body.getBytes());  
337.             os.flush();  
338.             os.close();  
339.         }  
340.           
341.         // response  
342.         InputStream is = conn.getInputStream();  
343.         String response = streamToString(is);  
344.         is.close();  
345.           
346.         // handle redirects  
347.         if (conn.getResponseCode() == 301) {  
348.             String location = conn.getHeaderField("Location");  
349.             return fetch(method, location, body, headers);  
350.         }  
351.           
352.         return response;  
353.     }  
354.       
355.     /** 
356.      * Read an input stream into a string 
357.      * @param in 
358.      * @return 
359.      * @throws IOException 
360.      */  
361.     static public String streamToString(InputStream in) throws IOException {  
362.         StringBuffer out = new StringBuffer();  
363.         byte[] b = new byte[4096];  
364.         for (int n; (n = in.read(b)) != -1;) {  
365.             out.append(new String(b, 0, n));  
366.         }  
367.         return out.toString();  
368.     }  
369. }  
370.   
371.                       

/* *    Copyright 2012-2013 The Haohui Network Corporation */package com.haohui.common.utils;/** * @file HttpUtil.java *  * @brief  * HttpUtil is a single class containing methods to conveniently perform HTTP  * requests. HttpUtil only uses regular java io and net functionality and does  * not depend on external libraries.  * The class contains methods to perform a get, post, put, and delete request, * and supports posting forms. Optionally, one can provide headers. * * Example usage: *  *     // get *     String res = HttpUtil.get("http://www.zuidaima.com"); *  *     // post *     String res = HttpUtil.post("http://www.zuidaima.com/share/1550463379950592.htm", "This is the data"); * *     // post form *     Map<String, String> params = new HashMap<String, String>(); *     params.put("firstname", "Joe"); *     params.put("lastname", "Smith"); *     params.put("age", "28"); *     String res = HttpUtil.postForm("http://site.com/newuser", params); * *     // append query parameters to url *     String url = "http://mydatabase.com/users"; *     Map<String, String> params = new HashMap<String, String>(); *     params.put("orderby", "name"); *     params.put("limit", "10"); *     String fullUrl = HttpUtil.appendQueryParams(url, params); *     // fullUrl = "http://mydatabase.com/user?orderby=name&limit=10" * * @license * Licensed under the Apache License, Version 2.0 (the "License"); you may not * use this file except in compliance with the License. You may obtain a copy  * of the License at *  * http://www.apache.org/licenses/LICENSE-2.0 *  * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations under * the License. * * Copyright (c) 2012 Almende B.V. * * @author Jos de Jong, <[e-mail]> www.zuidaima.com * @date  2012-05-14 */import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.net.HttpURLConnection;import java.net.URL;import java.net.URLDecoder;import java.net.URLEncoder;import java.util.HashMap;import java.util.Map;/** * https://raw.github.com/wjosdejong/httputil/master/src/com/almende/util/HttpUtil.java *  * @project baidamei * @author cevencheng <[e-mail]> * @create 2012-11-17 下午2:35:38 */public class HttpUtil {/** * Send a get request * @param url * @return response * @throws IOException  */static public String get(String url) throws IOException {return get(url, null);}/** * Send a get request * @param url         Url as string * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String get(String url,Map<String, String> headers) throws IOException {return fetch("GET", url, null, headers);}/** * Send a post request * @param url         Url as string * @param body        Request body as string * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String post(String url, String body,Map<String, String> headers) throws IOException {return fetch("POST", url, body, headers);}/** * Send a post request * @param url         Url as string * @param body        Request body as string * @return response   Response as string * @throws IOException  */static public String post(String url, String body) throws IOException {return post(url, body, null);}/** * Post a form with parameters * @param url         Url as string * @param params      map with parameters/values * @return response   Response as string * @throws IOException  */static public String postForm(String url, Map<String, String> params) throws IOException {return postForm(url, params, null);}/** * Post a form with parameters * @param url         Url as string * @param params      Map with parameters/values * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String postForm(String url, Map<String, String> params,Map<String, String> headers) throws IOException {// set content typeif (headers == null) {headers = new HashMap<String, String>();}headers.put("Content-Type", "application/x-www-form-urlencoded");// parse parametersString body = "";if (params != null) {boolean first = true;for (String param : params.keySet()) {if (first) {first = false;}else {body += "&";}String value = params.get(param);body += URLEncoder.encode(param, "UTF-8") + "=";body += URLEncoder.encode(value, "UTF-8");}}return post(url, body, headers);}/** * Send a put request * @param url         Url as string * @param body        Request body as string * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String put(String url, String body,Map<String, String> headers) throws IOException {return fetch("PUT", url, body, headers);}/** * Send a put request * @param url         Url as string * @return response   Response as string * @throws IOException  */static public String put(String url, String body) throws IOException {return put(url, body, null);}/** * Send a delete request * @param url         Url as string * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String delete(String url,Map<String, String> headers) throws IOException {return fetch("DELETE", url, null, headers);}/** * Send a delete request * @param url         Url as string * @return response   Response as string * @throws IOException  */static public String delete(String url) throws IOException {return delete(url, null);}/** * Append query parameters to given url * @param url         Url as string * @param params      Map with query parameters * @return url        Url with query parameters appended * @throws IOException  */static public String appendQueryParams(String url, Map<String, String> params) throws IOException {String fullUrl = new String(url);if (params != null) {boolean first = (fullUrl.indexOf('?') == -1);for (String param : params.keySet()) {if (first) {fullUrl += '?';first = false;}else {fullUrl += '&';}String value = params.get(param);fullUrl += URLEncoder.encode(param, "UTF-8") + '=';fullUrl += URLEncoder.encode(value, "UTF-8");}}return fullUrl;}/** * Retrieve the query parameters from given url * @param url         Url containing query parameters * @return params     Map with query parameters * @throws IOException  */static public Map<String, String> getQueryParams(String url) throws IOException {Map<String, String> params = new HashMap<String, String>();int start = url.indexOf('?');while (start != -1) {// read parameter nameint equals = url.indexOf('=', start);String param = "";if (equals != -1) {param = url.substring(start + 1, equals);}else {param = url.substring(start + 1);}// read parameter valueString value = "";if (equals != -1) {start = url.indexOf('&', equals);if (start != -1) {value = url.substring(equals + 1, start);}else {value = url.substring(equals + 1);}}params.put(URLDecoder.decode(param, "UTF-8"), URLDecoder.decode(value, "UTF-8"));}return params;}/** * Returns the url without query parameters * @param url         Url containing query parameters * @return url        Url without query parameters * @throws IOException  */static public String removeQueryParams(String url) throws IOException {int q = url.indexOf('?');if (q != -1) {return url.substring(0, q);}else {return url;}}/** * Send a request * @param method      HTTP method, for example "GET" or "POST" * @param url         Url as string * @param body        Request body as string * @param headers     Optional map with headers * @return response   Response as string * @throws IOException  */static public String fetch(String method, String url, String body,Map<String, String> headers) throws IOException {// connectionURL u = new URL(url);HttpURLConnection conn = (HttpURLConnection)u.openConnection();conn.setConnectTimeout(10000);conn.setReadTimeout(10000);// methodif (method != null) {conn.setRequestMethod(method);}// headersif (headers != null) {for(String key : headers.keySet()) {conn.addRequestProperty(key, headers.get(key));}}// bodyif (body != null) {conn.setDoOutput(true);OutputStream os = conn.getOutputStream();os.write(body.getBytes());os.flush();os.close();}// responseInputStream is = conn.getInputStream();String response = streamToString(is);is.close();// handle redirectsif (conn.getResponseCode() == 301) {String location = conn.getHeaderField("Location");return fetch(method, location, body, headers);}return response;}/** * Read an input stream into a string * @param in * @return * @throws IOException */static public String streamToString(InputStream in) throws IOException {StringBuffer out = new StringBuffer();byte[] b = new byte[4096];for (int n; (n = in.read(b)) != -1;) {out.append(new String(b, 0, n));}return out.toString();}}