Java、Android實現表單提交——支持多文件同時上傳

在Android里面或者J2EE后台需要趴別人網站數據，模擬表單提交是一件很常見的事情，但是在Android里面要實現多文件上傳，還要夾着普通表單字段上傳，這下可能就有點費勁了，今天花時間整理了一個工具類，主要是借助於HttpClient，其實也很簡單，看一下代碼就非常清楚了

HttpClient工具類：

HttpClientUtil.java

package cn.com.ajava.util;

import java.io.File;
import java.io.Serializable;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.http.Consts;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

/**
 * HttpClient工具類
 * 
 * @author 曾繁添
 * @version 1.0
 */
public class HttpClientUtil
{

    public final static String Method_POST = "POST";

    public final static String Method_GET = "GET";

    /**
     * multipart/form-data類型的表單提交
     * 
     * @param form
     *            表單數據
     */
    public static String submitForm(MultipartForm form)
    {

        // 返回字符串
        String responseStr = "";

        // 創建HttpClient實例
        HttpClient httpClient = new DefaultHttpClient();

        try
        {
            // 實例化提交請求
            HttpPost httpPost = new HttpPost(form.getAction());

            // 創建MultipartEntityBuilder
            MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();

            // 追加普通表單字段
            Map<String, String> normalFieldMap = form.getNormalField();
            for (Iterator<Entry<String, String>> iterator = normalFieldMap.entrySet().iterator(); iterator.hasNext();)
            {
                Entry<String, String> entity = iterator.next();
                entityBuilder.addPart(entity.getKey(), new StringBody(entity.getValue(), ContentType.create("text/plain", Consts.UTF_8)));
            }

            // 追加文件字段
            Map<String, File> fileFieldMap = form.getFileField();
            for (Iterator<Entry<String, File>> iterator = fileFieldMap.entrySet().iterator(); iterator.hasNext();)
            {
                Entry<String, File> entity = iterator.next();
                entityBuilder.addPart(entity.getKey(), new FileBody(entity.getValue()));
            }

            // 設置請求實體
            httpPost.setEntity(entityBuilder.build());

            // 發送請求
            HttpResponse response = httpClient.execute(httpPost);
            int statusCode = response.getStatusLine().getStatusCode();
            // 取得響應數據
            HttpEntity resEntity = response.getEntity();
            if (200 == statusCode)
            {
                if (resEntity != null)
                {
                    responseStr = EntityUtils.toString(resEntity);
                }
            }
        } catch (Exception e)
        {
            System.out.println("提交表單失敗，原因：" + e.getMessage());
        } finally
        {

            httpClient.getConnectionManager().shutdown();
        }

        return responseStr;
    }

    /** 表單字段Bean */
    public class MultipartForm implements Serializable
    {
        /** 序列號 */
        private static final long serialVersionUID = -2138044819190537198L;

        /** 提交URL **/
        private String action = "";

        /** 提交方式：POST/GET **/
        private String method = "POST";

        /** 普通表單字段 **/
        private Map<String, String> normalField = new LinkedHashMap<String, String>();

        /** 文件字段 **/
        private Map<String, File> fileField = new LinkedHashMap<String, File>();

        public String getAction()
        {
            return action;
        }

        public void setAction(String action)
        {
            this.action = action;
        }

        public String getMethod()
        {
            return method;
        }

        public void setMethod(String method)
        {
            this.method = method;
        }

        public Map<String, String> getNormalField()
        {
            return normalField;
        }

        public void setNormalField(Map<String, String> normalField)
        {
            this.normalField = normalField;
        }

        public Map<String, File> getFileField()
        {
            return fileField;
        }

        public void setFileField(Map<String, File> fileField)
        {
            this.fileField = fileField;
        }

        public void addFileField(String key, File value)
        {
            fileField.put(key, value);
        }

        public void addNormalField(String key, String value)
        {
            normalField.put(key, value);
        }
    }

}

 

 服務器端實現文件上傳、並且讀取參數方法：（借助於Apache的fileupload組件實現，實現了獲取表單action后面直接拼接參數、表單普通項目、文件項目三種字段獲取方法）

 后台我就直接寫了一個Servlet，具體代碼如下：

ServletUploadFile.java

package cn.com.ajava.servlet;

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

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;

/**
 * 文件上傳Servlet
 * @author 曾繁添
 */
public class ServletUploadFile extends HttpServlet
{
  private static final long serialVersionUID = 1L;
  // 限制文件的上傳大小 1G
  private int maxPostSize = 1000 * 1024 * 10;

  public ServletUploadFile()
  {
    super();
  }

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException,
      IOException
  {
    doPost(request, response);
  }

  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException,
      IOException
  {
    PrintWriter out = response.getWriter();
    String contextPath = request.getSession().getServletContext().getRealPath("/");
    String webDir = "uploadfile" + File.separator + "images" + File.separator;
    String systemPath = request.getContextPath();
    String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort()+ systemPath + "/";
    request.setCharacterEncoding("UTF-8");
    response.setContentType("text/html;charset=UTF-8");

    try
    {
      DiskFileItemFactory factory = new DiskFileItemFactory();
      factory.setSizeThreshold(1024 * 4); // 設置寫入大小
      ServletFileUpload upload = new ServletFileUpload(factory);
      upload.setSizeMax(maxPostSize); // 設置文件上傳最大大小
      
      System.out.println(request.getContentType());
      //獲取action后面拼接的參數(如：http://www.baidu.com?q=android)
      Enumeration enumList = request.getParameterNames();
      while(enumList.hasMoreElements()){
        String key = (String)enumList.nextElement();
        String value = request.getParameter(key);
        System.out.println(key+"="+value);
      }
      
      //獲取提交表單項目
      List listItems = upload.parseRequest(request);
      Iterator iterator = listItems.iterator();
      while (iterator.hasNext())
      {
        FileItem item = (FileItem) iterator.next();
        //非普通表單項目
        if (!item.isFormField())
        {
        
         //獲取擴展名
          String ext = item.getName().substring(item.getName().lastIndexOf("."), item.getName().length());
          String fileName = System.currentTimeMillis() + ext;
          
          File dirFile = new File(contextPath + webDir + fileName);
          if (!dirFile.exists())
          {
            dirFile.getParentFile().mkdirs();
          }

          item.write(dirFile);
          System.out.println("fileName：" + item.getName() + "=====" + item.getFieldName() + " size： "+ item.getSize());
          System.out.println("文件已保存到： " + contextPath + webDir + fileName);
          //響應客戶端請求
          out.print(basePath + webDir.replace("\\", "/") + fileName);
          out.flush();
        }else{
          //普通表單項目
          System.out.println("表單普通項目："+item.getFieldName()+"=" + item.getString("UTF-8"));// 顯示表單內容。item.getString("UTF-8")可以保證中文內容不亂碼
        }
      }
    } catch (Exception e)
    {
      e.printStackTrace();
    } finally
    {
      out.close();
    }
  }
}

工具類、服務器端代碼上面都貼出來了，具體怎么調用應該就不需要說了吧？封裝的已經夠清晰明了了

調用示例DEMO：

//創建HttpClientUtil實例
HttpClientUtil httpClient = new HttpClientUtil();
MultipartForm form = httpClient.new MultipartForm();
//設置form屬性、參數
form.setAction("http://192.168.1.7:8080/UploadFileDemo/cn/com/ajava/servlet/ServletUploadFile");
File photoFile = new File(sddCardPath+"//data//me.jpg");
form.addFileField("photo", photoFile);
form.addNormalField("name", "曾繁添");
form.addNormalField("tel", "15122946685");
//提交表單
HttpClientUtil.submitForm(form);

最后說明一下jar問題：

要是android里面應用的話，需要注意一下額外引入httpmime-4.3.1.jar（我當時下的這個是最高版本了），至於fileUpload的jar，直接去apache官網下載吧