JSP实现文件上传

最新推荐文章于 2022-11-18 10:29:14 发布

原创最新推荐文章于 2022-11-18 10:29:14 发布 · 277 阅读

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#JSP #文件上传

话不多说,直接贴代码

UploadServletTest.java

package com.ujiuye.servlet;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.UUID;

import javax.servlet.ServletException;
import javax.servlet.ServletInputStream;
import javax.servlet.annotation.WebServlet;
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.FileUploadException;
import org.apache.commons.fileupload.ProgressListener;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

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

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		// 1. 自己推理的方法
		// fileUploadFunc1(request,response);
		
		try {
			
			// 2. 使用第三方包 将文件上传到项目目录下
			// fileUploadFunc2(request,response);
			
			// 3. 使用第三方包 将文件上传到磁盘下
			fileUploadFunc3(request,response);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		

	}

	private void fileUploadFunc3(HttpServletRequest request, HttpServletResponse response) throws Exception {
		// TODO Auto-generated method stub
		// 1. 判断form表单 enctype="multipart/form-data"
		boolean multipartContent = ServletFileUpload.isMultipartContent(request);
		
		if(multipartContent) {
			// 2. 处理文件上传
			// 2.0  创建磁盘解析工厂类
			DiskFileItemFactory factory = new DiskFileItemFactory();
			
			// 2.1 创建核心解析类
			ServletFileUpload upload = new ServletFileUpload(factory);
			
			
			// 4. 解决中文文件名乱码
			upload.setHeaderEncoding("UTF-8");
			
			// 8. 监听上传进度
			upload.setProgressListener(new ProgressListener() {
				
				// 参数1：已上传的大小  参数2：总大小  参数3：状态码
				@Override
				public void update(long arg0, long arg1, int arg2) {
					// TODO Auto-generated method stub
					System.out.println("已上传："+arg0+",总大小："+arg1+",状态："+arg2);
				}
			});
			
			
			// 7. 限制文件上传的大小
			// 7.1  文件上传的总大小   
			// upload.setSizeMax(1024*1024*10);  // 1TB = 1024GB = 1024*1024MB = 1024*1024*1024KB 
			
			upload.setFileSizeMax(1024*1024*5);
			
			// 2.2 开始解析
			List<FileItem> fileItems = upload.parseRequest(request);
			
			
			
			
			
			
			// 2.3 判断FileItem 是普通的输入框还是文件上传
			for (FileItem fileItem : fileItems) {
				if(fileItem.isFormField()) {
					// 普通的输入框
					String name = fileItem.getFieldName();
					
					
					// 3. 解决普通输入框文本乱码问题
					// String value = fileItem.getString();
					String value = fileItem.getString("UTF-8");
					
					System.out.println(name+"===>"+value);
				}else {
					// 文件上传
					// 1. 获取文件名
					
					String filename = fileItem.getName();
					if("".equals(filename)) {
						continue;
					}
					System.out.println("文件名："+filename);
					
					
					// 5. 随机文件名
					String uuid = UUID.randomUUID().toString().replace("-", "").toUpperCase();
					// System.out.println(uuid);
					
					filename = uuid+filename.substring(filename.indexOf("."));
					System.out.println(filename);
					
					
					// 9. 文件目录
					SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
					String format2 = format.format(new Date());
					
					// 2. 指定文件上传的路径
					File dir = new File("D://img//"+format2);
					if(!dir.exists()) {
						dir.mkdirs();
					}
					
					// 3. 将文件名 放入file路径中
					File file = new File(dir, filename);
					System.out.println("保存路径："+file);
					// 4. 将文件内容放入文件中
					fileItem.write(file);
				}
			}
			
			
		}
	}

	private void fileUploadFunc2(HttpServletRequest request, HttpServletResponse response) throws Exception {
		
		// 1. 检查我们是否有文件上传请求    判断form表单 enctype="multipart/form-data"
		boolean multipartContent = ServletFileUpload.isMultipartContent(request);
		
		// 2. true  文件上传   false  普通的form请求
		if(multipartContent) {
			// 3. 处理文件上传
			
			// 3.0  创建磁盘解析工厂类
			DiskFileItemFactory factory = new DiskFileItemFactory();
			
			// 3.1  创建核心解析类
			ServletFileUpload upload = new ServletFileUpload(factory);
			
			// 3.2 开始解析      form中的  每一个 input 输入框: FileItem
			List<FileItem> fileItems = upload.parseRequest(request);
			
			// 3.3  找不同的type  不同的处理
			for (FileItem fileItem : fileItems) {
				// 3.4 判断是否是 普通的input 框  还是  文件上传  type=file
				if(fileItem.isFormField()) {
					// 普通的输入框  只需要获取 name  和   value
					String name = fileItem.getFieldName();
					String value = fileItem.getString();
					
					System.out.println(name+":::"+value);
				}else {
					// 文件上传  
					// 1. 获取文件名
					String filename = fileItem.getName();
					System.out.println("文件名："+filename);
					
					// 2. 指定存放路径
					String realPath = getServletContext().getRealPath("/image");
					
					File dir = new File(realPath);
					
					if(!dir.exists()) {
						dir.mkdirs();
					}
					
					
					// 3. 将内容和文件名字 放入路径中
					File file = new File(dir, filename);
					System.out.println("保存路径："+file);
					
					
					// 4. 将内容写进去
					fileItem.write(file);
				}
			}
			
		}
		
		
	}

	private void fileUploadFunc1(HttpServletRequest request, HttpServletResponse response) throws IOException {
		// TODO Auto-generated method stub
		// 1. 获取请求数据
//		String desc = request.getParameter("desc");
//		
//		String file = request.getParameter("file1");
//				
//		System.out.println(desc+"::"+file);
		
		
		
		// 2. 获取请求数据 但是数据包含文件和form表单的
		ServletInputStream inputStream = request.getInputStream();
		
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		
		byte[] buff = new byte[4*1024];
		
		int len = 0;
		while((len=inputStream.read(buff))!=-1) {
			baos.write(buff, 0, len);
			baos.flush();
		}
		
		byte[] byteArray = baos.toByteArray();
		
		System.out.println(new String(byteArray));
		
	}

	/**
	 * @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);
	}

}

upload.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>
<script type="text/javascript">
	function checkFile(){
		var f1 = document.getElementById("f1");
		
		// files[0] 当前input中的file文件
		var file = f1.files[0];
		
		// 获取文件大小
		var size = file.size;
		// alert(size);
		
		if(size>1024*1024*5){
			alert(file.name+"：过大，不能上传！");
		}else{
			var fm = document.getElementById("fm");
			fm.submit();
		}
		
		
	}
</script>
</head>
<body>
	<form id="fm" action="uploadServletTest" method="post" enctype="multipart/form-data">
	
		<input type="text" name="desc" /><br />
		<input id="f1" type="file" name="file1" /><br />
		<input type="button" onclick="checkFile()" value="上传"/>
	</form>
</body>
</html>

img.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>
	<img alt="" src="/images/book2.jpg">
</body>
</html>