Java commons-upload 上传文件

//使用Commons-fileupload组件实现文件上传，需要导入该组件相应的支撑jar包：Commons-fileupload和commons-io

package com.qf.test;

import java.io.File;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import java.util.Date;
import java.util.List;
import java.util.UUID;

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;

/**
 * commons-upload 上传文件
 */
public class UploadServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doPost(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		//统一字符编码及响应类型
		request.setCharacterEncoding("utf-8");
		response.setCharacterEncoding("utf-8");
		response.setContentType("text/html");
		
		// 判断上传文件目录是否存在
		File file = new File("/upload");
		if (!file.exists()) {
			file.mkdirs();
		}
		// 判断上传的mimo编码方式
		if (ServletFileUpload.isMultipartContent(request)) {// 二进制

			try {
				// 创建解析器工厂对象
				DiskFileItemFactory factory = new DiskFileItemFactory();
				// 创建上传解析器对象
				ServletFileUpload sfu = new ServletFileUpload(factory);
				// 解析上传的表单元素并解析结果
				// 每一个FileItem 对应一个 request 请求中from表单中的 input 元素,解析 request请求，将request中提交的值存入List数组
				List<FileItem> fs = sfu.parseRequest(request);
				// 遍历解析每一个表单元素
				for (FileItem f : fs) {
					if (f.isFormField() == false) {// 当前表单元素是文件表单元素
						String fileName = f.getName();
						fileName = UUID.randomUUID() + "_" + fileName;// UUID方式解决重名的问题

						// 判断文件上传的类型
						if (fileName.endsWith(".jpg") || fileName.endsWith(".png")) {
							// 上传路径
							String path = request.getServletContext().getRealPath("/upload");
							// 上传的文件
							f.write(new File(path, fileName));
							response.getWriter().write("文件上传成功");

						} else {
							response.getWriter().write("上传的文件类型有误，只支持jpg,png类型！");
						}
					}
				}
			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				// 关流
				response.getWriter().close();
			}
		} else {// 字符串
			request.setAttribute("mess", "上传的编码方式有误！");
			request.getRequestDispatcher("upload1.jsp").forward(request, response);
		}
	}
}