uploadservlet.java

servlet实现网上书店查询

package com.ghy.bookstore.load.web;

import java.io.File;
import java.io.IOException;
import java.net.URLEncoder;
import java.sql.SQLException;
import java.util.ArrayList;
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 javax.servlet.http.HttpSession;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.FileUploadBase.SizeLimitExceededException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import com.ghy.bookstore.load.dao.FileLinkDao;
import com.ghy.bookstore.load.model.FileLinkVO;
import com.ghy.bookstore.user.model.UserVO;

public class UploadServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public UploadServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doPost(request, response);
	}

	/**
	 * The doPost method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to
	 * post.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		response.setContentType("text/html;charset=utf-8");
		request.setCharacterEncoding("utf-8");

		List fileList = null;
		final long MAX_SIZE = 3 * 1024 * 1024;

		final String[] allowedExt = new String[] { "jpg", "jpeg", "gif", "txt",
				"doc", "docx", "mp3", "wma", "m4a" };

		try {

			DiskFileItemFactory dfif = new DiskFileItemFactory();
			dfif.setSizeThreshold(4096);
			dfif.setRepository(new File(request.getRealPath("/")
					+ "ImagesUploadTemp"));
			ServletFileUpload sfu = new ServletFileUpload(dfif);
			sfu.setSizeMax(MAX_SIZE);
			fileList = sfu.parseRequest(request);
		} catch (FileUploadException e) {
			if (e instanceof SizeLimitExceededException) {
				String message = "文件尺寸超过规定大小" + MAX_SIZE / (1024 * 1024)
						+ "M大小";
				request.getRequestDispatcher(
						"/jsp/load/upload.jsp?message="
								+ URLEncoder.encode(message, "utf-8")).forward(
						request, response);
				return;
			}
			e.printStackTrace();
		}
		if (fileList == null || fileList.size() == 0) {

			String message = "请选择上传文件";
			request.getRequestDispatcher(
					"/jsp/load/upload.jsp?message="
							+ URLEncoder.encode(message, "utf-8")).forward(
					request, response);
			return;
		}

		Iterator fileItr = fileList.iterator();
		while (fileItr.hasNext()) {
			FileItem fileItem = null;
			String path = null;
			long size = 0;

			fileItem = (FileItem) fileItr.next();

			if (fileItem == null || fileItem.isFormField()) {
				continue;
			}

			path = fileItem.getName();
			size = fileItem.getSize();
			if ("".equals(path) || size == 0) {

				String message = "请选择上传文件";
				request.getRequestDispatcher(
						"/jsp/load/upload.jsp?message="
								+ URLEncoder.encode(message, "utf-8")).forward(
						request, response);
				return;
			}

			String t_name = path.substring(path.lastIndexOf("\\") + 1);
			String t_ext = t_name.substring(t_name.lastIndexOf(".") + 1);
			int allowFlag = 0;
			int allowedExtCount = allowedExt.length;
			for (; allowFlag < allowedExtCount; allowFlag++) {
				if (allowedExt[allowFlag].equals(t_ext))
					break;
			}
			if (allowFlag == allowedExtCount) {
				String message = "请上传以下类型文件";
				request.getRequestDispatcher(
						"/jsp/load/upload.jsp?message="
								+ URLEncoder.encode(message, "utf-8")).forward(
						request, response);
				return;
			}
			try {

				String u_name = request.getRealPath("/") + "imagesUploadTemp/"
						+ t_name;

				fileItem.write(new File(u_name));

				// 将上传文件信息存储到filelink表
				FileLinkVO filelink = new FileLinkVO();
				HttpSession session = request.getSession();
				UserVO user = (UserVO) session.getAttribute("CurrentUser");
				filelink.setUserid(user.getId());
				filelink.setFilename(t_name);
				filelink.setFilelink(u_name);
				new FileLinkDao().setFileLink(filelink);

				// 读取filelink表信息
				ArrayList list = new ArrayList();
				list = new FileLinkDao().getFileLink();
				session.setAttribute("fileLink", list);
				
				//重定向到upload.jsp
				String message = "文件上传成功:保存目录为:" + request.getRealPath("/")
						+ "ImagesUploadTemp" + "文件名为: " + t_name
						+ "&nbsp;&nbsp;文件大小: " + size + "字节";
				request.getRequestDispatcher(
						"/jsp/load/upload.jsp?message="
								+ URLEncoder.encode(message, "utf-8")).forward(
						request, response);
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	/**
	 * Initialization of the servlet. <br>
	 * 
	 * @throws ServletException
	 *             if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}