HttpClient4.5 简单入门实例

秒速五厘米 2022-09-30 13:52 166阅读 0赞

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一、所需要的jar包

httpclient-4.5.jar

httpcore-4.4.1.jar

httpmime-4.5.jar

二、实例

Java代码   ![收藏代码][icon_star.png]

1.  **package** cn.tzz.apache.httpclient;  
2.    
3.    
4.  **import** java.io.File;  
5.  **import** java.io.IOException;  
6.  **import** java.net.URL;  
7.  **import** java.util.ArrayList;  
8.  **import** java.util.List;  
9.  **import** java.util.Map;  
10.   
11. **import** org.apache.http.HttpEntity;  
12. **import** org.apache.http.NameValuePair;  
13. **import** org.apache.http.client.config.RequestConfig;  
14. **import** org.apache.http.client.entity.UrlEncodedFormEntity;  
15. **import** org.apache.http.client.methods.CloseableHttpResponse;  
16. **import** org.apache.http.client.methods.HttpGet;  
17. **import** org.apache.http.client.methods.HttpPost;  
18. **import** org.apache.http.conn.ssl.DefaultHostnameVerifier;  
19. **import** org.apache.http.conn.util.PublicSuffixMatcher;  
20. **import** org.apache.http.conn.util.PublicSuffixMatcherLoader;  
21. **import** org.apache.http.entity.ContentType;  
22. **import** org.apache.http.entity.StringEntity;  
23. **import** org.apache.http.entity.mime.MultipartEntityBuilder;  
24. **import** org.apache.http.entity.mime.content.FileBody;  
25. **import** org.apache.http.entity.mime.content.StringBody;  
26. **import** org.apache.http.impl.client.CloseableHttpClient;  
27. **import** org.apache.http.impl.client.HttpClients;  
28. **import** org.apache.http.message.BasicNameValuePair;  
29. **import** org.apache.http.util.EntityUtils;  
30.   
31.   
32. **public** **class** HttpClientUtil \{  
33.     **private** RequestConfig requestConfig = RequestConfig.custom()  
34.             .setSocketTimeout(15000)  
35.             .setConnectTimeout(15000)  
36.             .setConnectionRequestTimeout(15000)  
37.             .build();  
38.       
39.     **private** **static** HttpClientUtil instance = **null**;  
40.     **private** HttpClientUtil()\{\}  
41.     **public** **static** HttpClientUtil getInstance()\{  
42.         **if** (instance == **null**) \{  
43.             instance = **new** HttpClientUtil();  
44.         \}  
45.         **return** instance;  
46.     \}  
47.       
48.     /\*\* 
49.      \* 发送 post请求 
50.      \* @param httpUrl 地址 
51.      \*/  
52.     **public** String sendHttpPost(String httpUrl) \{  
53.         HttpPost httpPost = **new** HttpPost(httpUrl);// 创建httpPost    
54.         **return** sendHttpPost(httpPost);  
55.     \}  
56.       
57.     /\*\* 
58.      \* 发送 post请求 
59.      \* @param httpUrl 地址 
60.      \* @param params 参数(格式:key1=value1&key2=value2) 
61.      \*/  
62.     **public** String sendHttpPost(String httpUrl, String params) \{  
63.         HttpPost httpPost = **new** HttpPost(httpUrl);// 创建httpPost    
64.         **try** \{  
65.             //设置参数  
66.             StringEntity stringEntity = **new** StringEntity(params, "UTF-8");  
67.             stringEntity.setContentType("application/x-www-form-urlencoded");  
68.             httpPost.setEntity(stringEntity);  
69.         \} **catch** (Exception e) \{  
70.             e.printStackTrace();  
71.         \}  
72.         **return** sendHttpPost(httpPost);  
73.     \}  
74.       
75.     /\*\* 
76.      \* 发送 post请求 
77.      \* @param httpUrl 地址 
78.      \* @param maps 参数 
79.      \*/  
80.     **public** String sendHttpPost(String httpUrl, Map<String, String> maps) \{  
81.         HttpPost httpPost = **new** HttpPost(httpUrl);// 创建httpPost    
82.         // 创建参数队列    
83.         List<NameValuePair> nameValuePairs = **new** ArrayList<NameValuePair>();  
84.         **for** (String key : maps.keySet()) \{  
85.             nameValuePairs.add(**new** BasicNameValuePair(key, maps.get(key)));  
86.         \}  
87.         **try** \{  
88.             httpPost.setEntity(**new** UrlEncodedFormEntity(nameValuePairs, "UTF-8"));  
89.         \} **catch** (Exception e) \{  
90.             e.printStackTrace();  
91.         \}  
92.         **return** sendHttpPost(httpPost);  
93.     \}  
94.       
95.       
96.     /\*\* 
97.      \* 发送 post请求（带文件） 
98.      \* @param httpUrl 地址 
99.      \* @param maps 参数 
100.      \* @param fileLists 附件 
101.      \*/  
102.     **public** String sendHttpPost(String httpUrl, Map<String, String> maps, List<File> fileLists) \{  
103.         HttpPost httpPost = **new** HttpPost(httpUrl);// 创建httpPost    
104.         MultipartEntityBuilder meBuilder = MultipartEntityBuilder.create();  
105.         **for** (String key : maps.keySet()) \{  
106.             meBuilder.addPart(key, **new** StringBody(maps.get(key), ContentType.TEXT\_PLAIN));  
107.         \}  
108.         **for**(File file : fileLists) \{  
109.             FileBody fileBody = **new** FileBody(file);  
110.             meBuilder.addPart("files", fileBody);  
111.         \}  
112.         HttpEntity reqEntity = meBuilder.build();  
113.         httpPost.setEntity(reqEntity);  
114.         **return** sendHttpPost(httpPost);  
115.     \}  
116.       
117.     /\*\* 
118.      \* 发送Post请求 
119.      \* @param httpPost 
120.      \* @return 
121.      \*/  
122.     **private** String sendHttpPost(HttpPost httpPost) \{  
123.         CloseableHttpClient httpClient = **null**;  
124.         CloseableHttpResponse response = **null**;  
125.         HttpEntity entity = **null**;  
126.         String responseContent = **null**;  
127.         **try** \{  
128.             // 创建默认的httpClient实例.  
129.             httpClient = HttpClients.createDefault();  
130.             httpPost.setConfig(requestConfig);  
131.             // 执行请求  
132.             response = httpClient.execute(httpPost);  
133.             entity = response.getEntity();  
134.             responseContent = EntityUtils.toString(entity, "UTF-8");  
135.         \} **catch** (Exception e) \{  
136.             e.printStackTrace();  
137.         \} **finally** \{  
138.             **try** \{  
139.                 // 关闭连接,释放资源  
140.                 **if** (response != **null**) \{  
141.                     response.close();  
142.                 \}  
143.                 **if** (httpClient != **null**) \{  
144.                     httpClient.close();  
145.                 \}  
146.             \} **catch** (IOException e) \{  
147.                 e.printStackTrace();  
148.             \}  
149.         \}  
150.         **return** responseContent;  
151.     \}  
152.   
153.     /\*\* 
154.      \* 发送 get请求 
155.      \* @param httpUrl 
156.      \*/  
157.     **public** String sendHttpGet(String httpUrl) \{  
158.         HttpGet httpGet = **new** HttpGet(httpUrl);// 创建get请求  
159.         **return** sendHttpGet(httpGet);  
160.     \}  
161.       
162.     /\*\* 
163.      \* 发送 get请求Https 
164.      \* @param httpUrl 
165.      \*/  
166.     **public** String sendHttpsGet(String httpUrl) \{  
167.         HttpGet httpGet = **new** HttpGet(httpUrl);// 创建get请求  
168.         **return** sendHttpsGet(httpGet);  
169.     \}  
170.       
171.     /\*\* 
172.      \* 发送Get请求 
173.      \* @param httpPost 
174.      \* @return 
175.      \*/  
176.     **private** String sendHttpGet(HttpGet httpGet) \{  
177.         CloseableHttpClient httpClient = **null**;  
178.         CloseableHttpResponse response = **null**;  
179.         HttpEntity entity = **null**;  
180.         String responseContent = **null**;  
181.         **try** \{  
182.             // 创建默认的httpClient实例.  
183.             httpClient = HttpClients.createDefault();  
184.             httpGet.setConfig(requestConfig);  
185.             // 执行请求  
186.             response = httpClient.execute(httpGet);  
187.             entity = response.getEntity();  
188.             responseContent = EntityUtils.toString(entity, "UTF-8");  
189.         \} **catch** (Exception e) \{  
190.             e.printStackTrace();  
191.         \} **finally** \{  
192.             **try** \{  
193.                 // 关闭连接,释放资源  
194.                 **if** (response != **null**) \{  
195.                     response.close();  
196.                 \}  
197.                 **if** (httpClient != **null**) \{  
198.                     httpClient.close();  
199.                 \}  
200.             \} **catch** (IOException e) \{  
201.                 e.printStackTrace();  
202.             \}  
203.         \}  
204.         **return** responseContent;  
205.     \}  
206.       
207.     /\*\* 
208.      \* 发送Get请求Https 
209.      \* @param httpPost 
210.      \* @return 
211.      \*/  
212.     **private** String sendHttpsGet(HttpGet httpGet) \{  
213.         CloseableHttpClient httpClient = **null**;  
214.         CloseableHttpResponse response = **null**;  
215.         HttpEntity entity = **null**;  
216.         String responseContent = **null**;  
217.         **try** \{  
218.             // 创建默认的httpClient实例.  
219.             PublicSuffixMatcher publicSuffixMatcher = PublicSuffixMatcherLoader.load(**new** URL(httpGet.getURI().toString()));  
220.             DefaultHostnameVerifier hostnameVerifier = **new** DefaultHostnameVerifier(publicSuffixMatcher);  
221.             httpClient = HttpClients.custom().setSSLHostnameVerifier(hostnameVerifier).build();  
222.             httpGet.setConfig(requestConfig);  
223.             // 执行请求  
224.             response = httpClient.execute(httpGet);  
225.             entity = response.getEntity();  
226.             responseContent = EntityUtils.toString(entity, "UTF-8");  
227.         \} **catch** (Exception e) \{  
228.             e.printStackTrace();  
229.         \} **finally** \{  
230.             **try** \{  
231.                 // 关闭连接,释放资源  
232.                 **if** (response != **null**) \{  
233.                     response.close();  
234.                 \}  
235.                 **if** (httpClient != **null**) \{  
236.                     httpClient.close();  
237.                 \}  
238.             \} **catch** (IOException e) \{  
239.                 e.printStackTrace();  
240.             \}  
241.         \}  
242.         **return** responseContent;  
243.     \}  
244. \}

三、测试代码

Java代码   ![收藏代码][icon_star.png]

1.  **package** cn.tzz.apache.httpclient;  
2.    
3.  **import** java.io.File;  
4.  **import** java.util.ArrayList;  
5.  **import** java.util.HashMap;  
6.  **import** java.util.List;  
7.  **import** java.util.Map;  
8.    
9.  **import** org.junit.Test;  
10.   
11. **public** **class** HttpClientUtilTest \{  
12.       
13.     @Test  
14.     **public** **void** testSendHttpPost1() \{  
15.         String responseContent = HttpClientUtil.getInstance()  
16.                 .sendHttpPost("http://localhost:8089/test/send?username=test01&password=123456");  
17.         System.out.println("reponse content:" + responseContent);  
18.     \}  
19.       
20.     @Test  
21.     **public** **void** testSendHttpPost2() \{  
22.         String responseContent = HttpClientUtil.getInstance()  
23.                 .sendHttpPost("http://localhost:8089/test/send", "username=test01&password=123456");  
24.         System.out.println("reponse content:" + responseContent);  
25.     \}  
26.       
27.     @Test  
28.     **public** **void** testSendHttpPost3() \{  
29.         Map<String, String> maps = **new** HashMap<String, String>();  
30.         maps.put("username", "test01");  
31.         maps.put("password", "123456");  
32.         String responseContent = HttpClientUtil.getInstance()  
33.                 .sendHttpPost("http://localhost:8089/test/send", maps);  
34.         System.out.println("reponse content:" + responseContent);  
35.     \}  
36.     @Test  
37.     **public** **void** testSendHttpPost4() \{  
38.         Map<String, String> maps = **new** HashMap<String, String>();  
39.         maps.put("username", "test01");  
40.         maps.put("password", "123456");  
41.         List<File> fileLists = **new** ArrayList<File>();  
42.         fileLists.add(**new** File("D://test//httpclient//1.png"));  
43.         fileLists.add(**new** File("D://test//httpclient//1.txt"));  
44.         String responseContent = HttpClientUtil.getInstance()  
45.                 .sendHttpPost("http://localhost:8089/test/sendpost/file", maps, fileLists);  
46.         System.out.println("reponse content:" + responseContent);  
47.     \}  
48.   
49.     @Test  
50.     **public** **void** testSendHttpGet() \{  
51.         String responseContent = HttpClientUtil.getInstance()  
52.                 .sendHttpGet("http://localhost:8089/test/send?username=test01&password=123456");  
53.         System.out.println("reponse content:" + responseContent);  
54.     \}  
55.       
56.     @Test  
57.     **public** **void** testSendHttpsGet() \{  
58.         String responseContent = HttpClientUtil.getInstance()  
59.                 .sendHttpsGet("https://www.baidu.com");  
60.         System.out.println("reponse content:" + responseContent);  
61.     \}  
62.   
63. \}

Java代码   ![收藏代码][icon_star.png]

1.  @RequestMapping(value = "/test/send")  
2.      @ResponseBody  
3.      **public** Map<String, String> sendPost(HttpServletRequest request) \{  
4.          Map<String, String> maps = **new** HashMap<String, String>();  
5.          String username = request.getParameter("username");  
6.          String password = request.getParameter("password");  
7.          maps.put("username", username);  
8.          maps.put("password", password);  
9.          **return** maps;  
10.     \}  
11.       
12.     @RequestMapping(value = "/test/sendpost/file",method=RequestMethod.POST)  
13.     @ResponseBody  
14.     **public** Map<String, String> sendPostFile(@RequestParam("files") MultipartFile \[\] files,HttpServletRequest request) \{  
15.         Map<String, String> maps = **new** HashMap<String, String>();  
16.         String username = request.getParameter("username");  
17.         String password = request.getParameter("password");  
18.         maps.put("username", username);  
19.         maps.put("password", password);  
20.           
21.         **try** \{  
22.             **for**(MultipartFile file : files)\{  
23.                 String fileName = file.getOriginalFilename();  
24.                 fileName = **new** String(fileName.getBytes(),"UTF-8");  
25.                 InputStream is = file.getInputStream();  
26.                 **if** (fileName != **null** && !("".equals(fileName))) \{  
27.                     File directory = **new** File("D://test//httpclient//file");  
28.                     **if** (!directory.exists()) \{  
29.                         directory.mkdirs();  
30.                     \}  
31.                     String filePath = ("D://test//httpclient//file") + File.separator + fileName;  
32.                     FileOutputStream fos = **new** FileOutputStream(filePath);  
33.                     **byte**\[\] buffer = **new** **byte**\[1024\];  
34.                     **while** (is.read(buffer) > 0) \{  
35.                         fos.write(buffer, 0, buffer.length);  
36.                     \}  
37.                     fos.flush();  
38.                     fos.close();  
39.                     maps.put("file--"\+fileName, "uploadSuccess");  
40.                 \}  
41.             \}  
42.         \} **catch** (Exception e) \{  
43.             e.printStackTrace();  
44.         \}  
45.         **return** maps;  
46.     \}

[icon_star.png]: /images/20220705/1aa82910c85641b9915c7e9fa65e9c16.png