採用multipart/form-data方式 調用上傳圖片接口

需求： 在手機客戶端調用服務器端接口 把手機中的圖片上傳到 接口提供的服務器上。

例如 新浪微博中的 發表附帶圖片的微博。 

注：這裏最好不要用socker編程來實現，由於當圖片過大的時候，圖片被解析成二進制(或者字節   數組)經過socker流傳過來的時候比較慢，當網絡慢的時候每每會由於超時拋異常致使不能調用接口 成功。  

其實能夠在客戶端模擬表單提交同樣，把圖片附件上傳到接口提供的服務器上。

 新浪和騰訊的微博都是這樣實現的，具體能夠參考： 

新浪微博接口：  http://open.weibo.com/wiki/Statuses/upload  

騰訊微博接口：  http://wiki.open.t.qq.com/index.php/API%E6%96%87%E6%A1%A3/%E5%BE%AE%E5%8D%9A%E6%8E%A5%E5%8F%A3/%E5%8F%91%E8%A1%A8%E4%B8%80%E6%9D%A1%E5%B8%A6%E5%9B%BE%E7%89%87%E7%9A%84%E5%BE%AE%E5%8D%9A

個人實現代碼以下（測試經過）：


客戶端調用代碼：

package com.common.myTest;

import java.io.File;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.multipart.FilePart;
import org.apache.commons.httpclient.methods.multipart.MultipartRequestEntity;
import org.apache.commons.httpclient.methods.multipart.Part;
public class Hclient {
 public static void main(String args[]) {
  String targetURL = null; //-- 指定URL
  File targetFile = null; //-- 指定上傳文件
  targetFile = new File("D:\\image1\\超大圖片.jpg");
  targetURL = "http://localhost:8080/servlet/HServlets"; // servleturl
  PostMethod filePost = new PostMethod(targetURL);
  try {
   // 經過如下方法能夠模擬頁面參數提交
   Part[] parts = { new FilePart(targetFile.getName(), targetFile) };
   filePost.setRequestEntity(new MultipartRequestEntity(parts,
     filePost.getParams()));
   HttpClient client = new HttpClient();
   client.getHttpConnectionManager().getParams().setConnectionTimeout(
     5000);
   int status = client.executeMethod(filePost);
   if (status == HttpStatus.SC_OK) {
    System.out.println("上傳成功");
    // 上傳成功
   } else {
    System.out.println("上傳失敗");
    // 上傳失敗
   }
  } catch (Exception ex) {
   ex.printStackTrace();
  } finally {
   filePost.releaseConnection();
  }
 }
}

服務器端代碼：

package com.common.myTest;

import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class HServlets extends HttpServlet {
    private Log log = LogFactory.getLog(HServlets.class);
 private static final long serialVersionUID = 1L;
 private String uploadPath; // 上傳文件的目錄
 private String tempPath; // 臨時文件目錄
 File tempPathFile;

 public void init(ServletConfig config) throws ServletException {
  super.init(config);
  uploadPath = config.getServletContext().getInitParameter("imageStorePath");
  tempPath = config.getServletContext().getInitParameter("images_120");
  
  File uploadFile = new File(uploadPath);
  if (!uploadFile.exists()) {
   uploadFile.mkdirs();
  }
  File tempPathFile = new File(tempPath);
  if (!tempPathFile.exists()) {
   tempPathFile.mkdirs();
  }
 }

 @SuppressWarnings("unchecked")
 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  try {
      log.info("進入上傳圖片的servlt");

   DiskFileItemFactory factory = new DiskFileItemFactory();
   factory.setSizeThreshold(4096); // 設置緩衝區大小，這裏是4kb
   factory.setRepository(tempPathFile);// 設置緩衝區目錄

   ServletFileUpload upload = new ServletFileUpload(factory);
   upload.setSizeMax(4194304); // 設置最大文件尺寸，這裏是4MB
   List<FileItem> items = upload.parseRequest(request);// 獲得全部的文件
   Iterator<FileItem> i = items.iterator();
   while (i.hasNext()) {
    FileItem fi = (FileItem) i.next();
    String fileName = fi.getName();
    log.info("上傳圖片的名字："+fileName);
    if (fileName != null) {
     File fullFile = new File(fi.getName());
     File savedFile = new File(uploadPath, fullFile.getName());
     fi.write(savedFile);
    }
   }
   log.info("上傳成功!");
  } catch (Exception e) {
   log.info(e.getMessage());
   // 能夠跳轉出錯頁面
   e.printStackTrace();
  }
 }


}