JavaWeb 文件上传 commons_fileupload方式

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

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;

/**
 * Created with IntelliJ IDEA.
 * User: HYY
 * Date: 13-11-17
 * Time: 下午4:13
 * To change this template use File | Settings | File Templates.
 */

/**
 * @author XHW
 * @date 2011-7-26
 */
public class FileUploadServlet extends HttpServlet {

    private static final long serialVersionUID = -7744625344830285257L;
    private ServletContext sc;
    private String savePath;

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

    public void init(ServletConfig config) {
        //保证根目录下有一个savePath目录
        savePath = "/savePath";
        sc = config.getServletContext();
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        DiskFileItemFactory factory = new DiskFileItemFactory();
        ServletFileUpload upload = new ServletFileUpload(factory);
        try {
            List items = upload.parseRequest(request);
            Iterator itr = items.iterator();
            while (itr.hasNext()) {
                FileItem item = (FileItem) itr.next();
                if (item.isFormField()) {
                    System.out.println("表单参数名:" + item.getFieldName() + "，表单参数值:" + item.getString("UTF-8"));
                } else {
                    if (item.getName() != null && !item.getName().equals("")) {
                        System.out.println("上传文件的大小:" + item.getSize());
                        System.out.println("上传文件的类型:" + item.getContentType());
                        // item.getName()返回上传文件在客户端的完整路径名称
                        System.out.println("上传文件的名称:" + item.getName());

                        File tempFile = new File(item.getName());

                        //上传文件的保存路径
                        File file = new File(sc.getRealPath("/") + savePath, tempFile.getName());
                        item.write(file);
                        request.setAttribute("upload.message", "上传文件成功！");
                    } else {
                        request.setAttribute("upload.message", "没有选择上传文件！");
                    }
                }
            }
        } catch (FileUploadException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
            request.setAttribute("upload.message", "上传文件失败！");
        }
        request.getRequestDispatcher("/uploadResult.jsp").forward(request, response);
    }
}

使用该程序时必须保证在根目录下有一个名为savePath文件夹

至于jsp方面就不写了。