java模拟post方式提交表单实现图片上传

模拟表单html如下:

 

 
   
 
 
  
   
 
 
  
 
 
 

 

 

java代码如下:

 

 package com.yanek.util;

 import java.io.BufferedReader;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;

 import javax.activation.MimetypesFileTypeMap;

 import net.sf.json.JSONArray;
 import net.sf.json.JSONObject;

 public class HttpPostUploadUtil {

     /**
      * @param args
      */
     public static void main(String[] args) {

         String filepath="E:\\ziliao\\0.jpg";

         String urlStr = "http://127.0.0.1:8080/minicms/up/up_result.jsp";

         Map textMap = new HashMap();

         textMap.put("name", "testname");

         Map fileMap = new HashMap();

         fileMap.put("userfile", filepath);

         String ret = formUpload(urlStr, textMap, fileMap);

         System.out.println(ret);


     }



     /**
      * 上传图片
      *
      * @param urlStr
      * @param textMap
      * @param fileMap
      * @return
      */
     public static String formUpload(String urlStr, Map textMap,
             Map fileMap) {
         String res = "";
         HttpURLConnection conn = null;
         String BOUNDARY = "---------------------------123821742118716"; //boundary就是request头和上传文件内容的分隔符
         try {
             URL url = new URL(urlStr);
             conn = (HttpURLConnection) url.openConnection();
             conn.setConnectTimeout(5000);
             conn.setReadTimeout(30000);
             conn.setDoOutput(true);
             conn.setDoInput(true);
             conn.setUseCaches(false);
             conn.setRequestMethod("POST");
             conn.setRequestProperty("Connection", "Keep-Alive");
             conn
                     .setRequestProperty("User-Agent",
                             "Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)");
             conn.setRequestProperty("Content-Type",
                     "multipart/form-data; boundary=" + BOUNDARY);

             OutputStream out = new DataOutputStream(conn.getOutputStream());
             // text
             if (textMap != null) {
                 StringBuffer strBuf = new StringBuffer();
                 Iterator iter = textMap.entrySet().iterator();
                 while (iter.hasNext()) {
                     Map.Entry entry = (Map.Entry) iter.next();
                     String inputName = (String) entry.getKey();
                     String inputValue = (String) entry.getValue();
                     if (inputValue == null) {
                         continue;
                     }
                     strBuf.append("\r\n").append("--").append(BOUNDARY).append(
                             "\r\n");
                     strBuf.append("Content-Disposition: form-data; name=\""
                             + inputName + "\"\r\n\r\n");
                     strBuf.append(inputValue);
                 }
                 out.write(strBuf.toString().getBytes());
             }

             // file
             if (fileMap != null) {
                 Iterator iter = fileMap.entrySet().iterator();
                 while (iter.hasNext()) {
                     Map.Entry entry = (Map.Entry) iter.next();
                     String inputName = (String) entry.getKey();
                     String inputValue = (String) entry.getValue();
                     if (inputValue == null) {
                         continue;
                     }
                     File file = new File(inputValue);
                     String filename = file.getName();
                     String contentType = new MimetypesFileTypeMap()
                             .getContentType(file);
                     if (filename.endsWith(".png")) {
                         contentType = "image/png";
                     }
                     if (contentType == null || contentType.equals("")) {
                         contentType = "application/octet-stream";
                     }

                     StringBuffer strBuf = new StringBuffer();
                     strBuf.append("\r\n").append("--").append(BOUNDARY).append(
                             "\r\n");
                     strBuf.append("Content-Disposition: form-data; name=\""
                             + inputName + "\"; filename=\"" + filename
                             + "\"\r\n");
                     strBuf.append("Content-Type:" + contentType + "\r\n\r\n");

                     out.write(strBuf.toString().getBytes());

                     DataInputStream in = new DataInputStream(
                             new FileInputStream(file));
                     int bytes = 0;
                     byte[] bufferOut = new byte[1024];
                     while ((bytes = in.read(bufferOut)) != -1) {
                         out.write(bufferOut, 0, bytes);
                     }
                     in.close();
                 }
             }

             byte[] endData = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();
             out.write(endData);
             out.flush();
             out.close();

             // 读取返回数据
             StringBuffer strBuf = new StringBuffer();
             BufferedReader reader = new BufferedReader(new InputStreamReader(
                     conn.getInputStream()));
             String line = null;
             while ((line = reader.readLine()) != null) {
                 strBuf.append(line).append("\n");
             }
             res = strBuf.toString();
             reader.close();
             reader = null;
         } catch (Exception e) {
             System.out.println("发送POST请求出错。" + urlStr);
             e.printStackTrace();
         } finally {
             if (conn != null) {
                 conn.disconnect();
                 conn = null;
             }
         }
         return res;
     }

 }