servlet文件上传源码

1、需要两个Jar包分别是commons-io-1.4.jar，commons-fileupload-1.2.1.jar。

2、还需要在根目录下新建一个文件夹uploads，用于保存上传后文件。

3、下面是上传Servlet类源码：

 

import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import org.apache.commons.fileupload.*;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

public class UploadServlet extends HttpServlet {
    private static final long serialVersionUID = -2201219701121037194L;
    private String savePath;
    private ServletContext sc;

    public void init(ServletConfig config) {
        savePath = config.getInitParameter("savePath");
        sc = config.getServletContext();
    }

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

    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);// 上传文件解析
            Iterator itr = items.iterator();// 枚举方法
            while (itr.hasNext()) {
                FileItem item = (FileItem) itr.next();
                if (item.isFormField()) {// 判断是文件还是文本信息
                    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("")) {// 判断是否选择了文件
                        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());
                        // 此时文件暂存在服务器的内存当中

                        File tempFile = new File(item.getName());// 构造临时对象
                        File file = new File(sc.getRealPath("/") + savePath,
                                tempFile.getName());
                        // 获取根目录对应的真实物理路径
                        item.write(file);// 保存文件在服务器的物理磁盘中
                        request.setAttribute("upload.message", "上传文件成功！");// 返回上传结果
                    } else {
                        request.setAttribute("upload.message", "没有选择上传文件！");
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            request.setAttribute("upload.message", "上传文件失败！");
        }
        request.getRequestDispatcher("/uploadResult.jsp").forward(request,
                response);
    }
}