文件上传服务器（附源码）-文件上传

此篇文章为文件上传，使用NIO提高性能读写速度，因项目需要因此是查找网上资源并进行相应的修改的Demo，程序已验证可以正常执行，希望对各位有一定帮助。

文件上传服务器（附源码）

项目结构，项目名为efg,包名com.abc.util

以上为Demo的目录结构，项目名请修改为efg若设置其他名字，请一并修改web.xml中的"<display-name>efg</display-name>",包名请设置为com.abc.util,若设置为其他包名，请一并修改web.xml中的“<servlet-class>com.abc.util.UploadHandleServlet2</servlet-class>”包名部分。

1.web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
 <display-name>efg</display-name>
 <welcome-file-list>
 <welcome-file>index.html</welcome-file>
 <welcome-file>index.htm</welcome-file>
 <welcome-file>index.jsp</welcome-file>
 <welcome-file>default.html</welcome-file>
 <welcome-file>default.htm</welcome-file>
 <welcome-file>default.jsp</welcome-file>
 </welcome-file-list>
 
 <servlet>
 <servlet-name>fileUp</servlet-name>
 <servlet-class>com.abc.util.UploadHandleServlet2</servlet-class>
 </servlet>
 
 <servlet-mapping>
 <servlet-name>fileUp</servlet-name>
 <url-pattern>*.do</url-pattern>
 </servlet-mapping>
</web-app>

2.index.jsp 文件上传页面

< page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"gt;
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
	<div>
		<h3>文件上传</h3>
		<form action="${pageContext.request.contextPath }/fileUp.do" method="post" enctype="multipart/form-data">
			<div>
				<p>
					上传人姓名：<input type="text" name="username">
				</p>
				<p>
					上传文件1：<input type="file" name="file1">
				</p>
				<p>
					上传文件2：<input type="file" name="file2">
				</p>
				<p>
					提交：<input type="submit" value="提交">
				</p>
			</div>
		</form>
	</div>
</body>
</html>

3.message.jsp 上传后返回信息页面

< page language="java" contentType="text/html; charset=UTF-8"
 pageEncoding="UTF-8"gt;
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
${message }
</body>
</html>

4.UploadHandleServlet 核心功能类如修改包名请再同步修改类中的packge

package com.abc.util;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.util.List;
import java.util.UUID;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadBase;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.ProgressListener;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class UploadHandleServlet2 extends HttpServlet {
	@Override
	protected void service(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		String savePath = this.getServletContext().getRealPath("/WEB-INF/upload");
		String tempPath = this.getServletContext().getRealPath("/WEB-INF/temp");
		File tempFile = new File(tempPath);
		if (!tempFile.exists() && !tempFile.isDirectory()) {
			tempFile.mkdirs();
		}
		String message = "";
		DiskFileItemFactory diskFileItemFactory = new DiskFileItemFactory();
		diskFileItemFactory.setSizeThreshold(DiskFileItemFactory.DEFAULT_SIZE_THRESHOLD * 10);
		diskFileItemFactory.setRepository(tempFile);
		ServletFileUpload servletFileUpload = new ServletFileUpload(diskFileItemFactory);
		servletFileUpload.setHeaderEncoding("UTF-8");
		if (!ServletFileUpload.isMultipartContent(request)) {
			request.setAttribute("message", "表单的enctype非文件上传方式!");
			request.getRequestDispatcher("/WEB-INF/jsp/message.jsp").forward(request, response);
			return;
		}
		servletFileUpload.setFileSizeMax(1024 * 1024);
		servletFileUpload.setSizeMax(1024 * 1024 * 10);
		servletFileUpload.setProgressListener(new ProgressListener() {
			@Override
			public void update(long pBytesRead, long pContentLength, int arg2) {
				System.out.println("文件大小为：" + pContentLength + ",当前已处理" + pBytesRead);
			}
		});
		try {
			List<FileItem> fileItems = servletFileUpload.parseRequest(request);
			for (FileItem fileItem : fileItems) {
				if (fileItem.isFormField()) {
					String name = fileItem.getFieldName();
					String value = fileItem.getString("UTF-8");
					System.out.println(name + ":" + value);
				} else {
					String fileName = fileItem.getName();
					if (fileName == null || fileName.trim().equals("")) {
						continue;
					}
					fileName = fileName.substring(fileName.lastIndexOf(File.separator) + 1);
					String fileExtName = fileName.substring(fileName.lastIndexOf(".") + 1);
					if ("rar".equals(fileExtName) || "tar".equals(fileExtName) || "zip".equals(fileExtName)
							|| "jar".equals(fileExtName)) {
						request.setAttribute("message", "文件格式错误!");
						request.getRequestDispatcher("/WEB-INF/jsp/message.jsp").forward(request, response);
						return;
					}
					InputStream is = fileItem.getInputStream();
					fileName = mkFileName(fileName);
					String savePathStr = mkFilePath(savePath, fileName);
					FileOutputStream fos = new FileOutputStream(savePathStr+File.separator+fileName);
					ReadableByteChannel readChannel = Channels.newChannel(is);
					WritableByteChannel writeChannel = Channels.newChannel(fos);
					ByteBuffer buffer = ByteBuffer.allocate(1024);
					int len = 0;
					while (true) {
						buffer.clear();
						len = readChannel.read(buffer);
						if (len < 0) {
							break;
						}
						buffer.flip();
						writeChannel.write(buffer);
					}
					is.close();
					fos.close();
					readChannel.close();
					writeChannel.close();
					fileItem.delete();
					message = "文件上传成功！";
				}
			}
		}catch (FileUploadBase.FileSizeLimitExceededException e) {
 e.printStackTrace();
 request.setAttribute("message", "单个文件超出最大值！！！");
 request.getRequestDispatcher("/WEB-INF/message.jsp").forward(request, response);
 return;
 }catch (FileUploadBase.SizeLimitExceededException e) {
 e.printStackTrace();
 request.setAttribute("message", "上传文件的总的大小超出限制的最大值！！！");
 request.getRequestDispatcher("/WEN-INF/message.jsp").forward(request, response);
 return;
 } catch (FileUploadException e) {
			e.printStackTrace();
			message = "文件上传失败";
		}
		request.setAttribute("message", message);
		request.getRequestDispatcher("/WEB-INF/jsp/message.jsp").forward(request, response);
	}
	private String mkFileName(String fileName) {
		return UUID.randomUUID().toString() + "_" + fileName;
	}
	private String mkFilePath(String savePath, String fileName) {
		int hashcode = fileName.hashCode();
		int dir1 = hashcode & 0xf;
		int dir2 = (hashcode & 0xf0) >> 4;
		String dir = savePath + "\\" + dir1 + "\\" + dir2;
		File file = new File(dir);
		if (!file.exists()) {
			file.mkdirs();
		}
		return dir;
	}
}