模擬表單html如下:

<form action="up_result.jsp" method="post" enctype="multipart/form-data" name="form1" id="form1">
 
    <label>
  <input type="text" name="name" value="" />
  </label>
  
    <label>
  <input type="file" name="userfile" />
  </label>
  
  <label>
  <input type="submit" value="上傳" />
  </label>
</form>

java程式碼如下:

1. package com.yanek.util;  
2. import java.io.BufferedReader;  
3. import java.io.DataInputStream;  
4. import java.io.DataOutputStream;  
5. import java.io.File;  
6. import java.io.FileInputStream;  
7. import java.io.InputStreamReader;  
8. import java.io.OutputStream;  
9. import java.net.HttpURLConnection;  
10. import java.net.URL;  
11. import java.util.HashMap;  
12. import java.util.Iterator;  
13. import java.util.Map;  
14. import javax.activation.MimetypesFileTypeMap;  
15. import net.sf.json.JSONArray;  
16. import net.sf.json.JSONObject;  
17. publicclass HttpPostUploadUtil {  
18.     /** 
19.      * @param args 
20.      */
21.     publicstatic
    void main(String[] args) {  
22.         String filepath="E:\\ziliao\\0.jpg";  
23.         String urlStr = "http://127.0.0.1:8080/minicms/up/up_result.jsp";  
24.         Map<String, String> textMap = new HashMap<String, String>();  
25.         textMap.put("name", "testname");  
26.         Map<String, String> fileMap = new HashMap<String, String>();  
27.         fileMap.put("userfile", filepath);  
28.         String ret = formUpload(urlStr, textMap, fileMap);  
29.         System.out.println(ret);  
30.     }  
31.     /** 
32.      * 上傳圖片 
33.      *  
34.      * @param urlStr 
35.      * @param textMap 
36.      * @param fileMap 
37.      * @return 
38.      */
39.     publicstatic String formUpload(String urlStr, Map<String, String> textMap,  
40.             Map<String, String> fileMap) {  
41.         String res = "";  
42.         HttpURLConnection conn = null;  
43.         String BOUNDARY = "---------------------------123821742118716"; //boundary就是request頭和上傳檔案內容的分隔符
44.         try {  
45.             URL url = new URL(urlStr);  
46.             conn = (HttpURLConnection) url.openConnection();  
47.             conn.setConnectTimeout(5000);  
48.             conn.setReadTimeout(30000);  
49.             conn.setDoOutput(true);  
50.             conn.setDoInput(true);  
51.             conn.setUseCaches(false);  
52.             conn.setRequestMethod("POST");  
53.             conn.setRequestProperty("Connection", "Keep-Alive");  
54.             conn  
55.                     .setRequestProperty("User-Agent",  
56.                             "Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)");  
57.             conn.setRequestProperty("Content-Type",  
58.                     "multipart/form-data; boundary=" + BOUNDARY);  
59.             OutputStream out = new DataOutputStream(conn.getOutputStream());  
60.             // text
61.             if (textMap != null) {  
62.                 StringBuffer strBuf = new StringBuffer();  
63.                 Iterator iter = textMap.entrySet().iterator();  
64.                 while (iter.hasNext()) {  
65.                     Map.Entry entry = (Map.Entry) iter.next();  
66.                     String inputName = (String) entry.getKey();  
67.                     String inputValue = (String) entry.getValue();  
68.                     if (inputValue == null) {  
69.                         continue;  
70.                     }  
71.                     strBuf.append("\r\n").append("--").append(BOUNDARY).append(  
72.                             "\r\n");  
73.                     strBuf.append("Content-Disposition: form-data; name=\""
74.                             + inputName + "\"\r\n\r\n");  
75.                     strBuf.append(inputValue);  
76.                 }  
77.                 out.write(strBuf.toString().getBytes());  
78.             }  
79.             // file
80.             if (fileMap != null) {  
81.                 Iterator iter = fileMap.entrySet().iterator();  
82.                 while (iter.hasNext()) {  
83.                     Map.Entry entry = (Map.Entry) iter.next();  
84.                     String inputName = (String) entry.getKey();  
85.                     String inputValue = (String) entry.getValue();  
86.                     if (inputValue == null) {  
87.                         continue;  
88.                     }  
89.                     File file = new File(inputValue);  
90.                     String filename = file.getName();  
91.                     String contentType = new MimetypesFileTypeMap()  
92.                             .getContentType(file);  
93.                     if (filename.endsWith(".png")) {  
94.                         contentType = "image/png";  
95.                     }  
96.                     if (contentType == null || contentType.equals("")) {  
97.                         contentType = "application/octet-stream";  
98.                     }  
99.                     StringBuffer strBuf = new StringBuffer();  
100.                     strBuf.append("\r\n").append("--").append(BOUNDARY).append(  
101.                             "\r\n");  
102.                     strBuf.append("Content-Disposition: form-data; name=\""
103.                             + inputName + "\"; filename=\"" + filename  
104.                             + "\"\r\n");  
105.                     strBuf.append("Content-Type:" + contentType + "\r\n\r\n");  
106.                     out.write(strBuf.toString().getBytes());  
107.                     DataInputStream in = new DataInputStream(  
108.                             new FileInputStream(file));  
109.                     int bytes = 0;  
110.                     byte[] bufferOut = newbyte[1024];  
111.                     while ((bytes = in.read(bufferOut)) != -1) {  
112.                         out.write(bufferOut, 0, bytes);  
113.                     }  
114.                     in.close();  
115.                 }  
116.             }  
117.             byte[] endData = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();  
118.             out.write(endData);  
119.             out.flush();  
120.             out.close();  
121.             // 讀取返回資料
122.             StringBuffer strBuf = new StringBuffer();  
123.             BufferedReader reader = new BufferedReader(new InputStreamReader(  
124.                     conn.getInputStream()));  
125.             String line = null;  
126.             while ((line = reader.readLine()) != null) {  
127.                 strBuf.append(line).append("\n");  
128.             }  
129.             res = strBuf.toString();  
130.             reader.close();  
131.             reader = null;  
132.         } catch (Exception e) {  
133.             System.out.println("傳送POST請求出錯。" + urlStr);  
134.             e.printStackTrace();  
135.         } finally {  
136.             if (conn != null) {  
137.                 conn.disconnect();  
138.                 conn = null;  
139.             }  
140.         }  
141.         return res;  
142.     }  
143. }