文件上传

新建项目后首先要记得导包，所以项目大概结构为：

jsp页面主要代码为：

<form action="upload" method="post" enctype="multipart/form-data">
		上传图片：<input type="file" name="file"/><br>	<br>	
		<input type="submit" value="确定" />
	</form>

新建一个servlet：

在doPost方法里写主要代码：

package cn.xxs.servlet;

import java.io.IOException;
import java.sql.SQLException;
import java.util.Date;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.jspsmart.upload.File;
import com.jspsmart.upload.SmartUpload;
import com.jspsmart.upload.SmartUploadException;

/**
 * Servlet implementation class UploadServlet
 */
@WebServlet("/upload")
public class UploadServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	/**
	 * @see HttpServlet#HttpServlet()
	 */
	public UploadServlet() {
		super();
		// TODO Auto-generated constructor stub
	}

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		// doGet(request, response);
		SmartUpload su = new SmartUpload();// 实例化
		su.initialize(getServletConfig(), request, response);// 初始化
		su.setMaxFileSize(10000000);
		su.setTotalMaxFileSize(100000000);
		su.setAllowedFilesList("jpg,png,gif");// 允许上传的格式
		try {
			su.setDeniedFilesList("rmvb,avi,mp4");// 不允许上传的格式
			try {
				su.upload();
				File file = su.getFiles().getFile(0);
				System.out.println(file.getFieldName());
				String path = request.getRealPath("/images/");
				file.saveAs(path + "/" + changeName(file.getFileName()));
			} catch (SmartUploadException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}

	// 改名字为上传时间+随机数+拓展名
	public String changeName(String oldName) {
		String expand = oldName.substring(oldName.lastIndexOf("."));// 截取拓展名
		Date d = new Date();
		Random r = new Random();
		return d.getTime() + r.nextInt(99999) + expand;

	}

}

然后运行，你会发现虽然成功了，但是你找不到你上传的文件。

这时候，你把你tomcat下项目remove了。

先右击它clean-->ok一下，再双击它进入一个窗口改成如图所示：

最后部署项目运行即可，上传的文件可在如下图所示位置找到：