第九课从零开始学Spring boot 之（文件上传）-优快云博客

一、单文件上传

1、在pom.xml加入相应依赖

<!-- thmleaf模板依赖. -->
       <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-thymeleaf</artifactId>
       </dependency>

<!-- thmleaf模板依赖. -->
       <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-thymeleaf</artifactId>
       </dependency>

<!-- thmleaf模板依赖. -->
       <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-thymeleaf</artifactId>
       </dependency>

2、编写controller

package com.gongh.controller;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;

@Controller
public class FileUploadController {
    
	@RequestMapping("/file")
    public String file(){
       return"/file";
    }
	/**
     * 文件上传具体实现方法;
     * @param file
     * @return
     */
    @RequestMapping("/upload")
    @ResponseBody
    public String handleFileUpload(@RequestParam("file")MultipartFile file){
    	if(!file.isEmpty()){
            try {

            	//获取文件名及后缀
            	String filename = file.getOriginalFilename();
            	String ext = filename.substring(filename.lastIndexOf("."));
            	System.out.print(filename+"---后缀---"+ext);
            	
            	//改文件名称
            	SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
            	String newFileName = sdf.format(new Date())+UUID.randomUUID()+ext;
            	
            	//项目根路径
            	HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();
            	String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath()  +"/"; 
            	
            	//文件存储路径
            	File savepath = new File(basePath +"static/uploadfile");
            	if (!savepath.exists()) {
            		savepath.mkdirs();
				}
                
            	/*
                * 图片上传到了工程的指定路径；
                */
               BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(new File(basePath +"static/uploadfile/"+newFileName)));
               out.write(file.getBytes());
               out.flush();
               out.close();
            } catch (FileNotFoundException e) {
               e.printStackTrace();
               return"upload failed,"+e.getMessage();
            } catch (IOException e) {
               e.printStackTrace();
               return"upload failed,"+e.getMessage();

            }
            return "upload success";

        }else{
            return"upload failed because the file is empty.";
        }
    }
    
   
}

3、在templates下新建一个file.html: 在src/main/resouces/templates(templates是spring boot存放模板文件的路径)，

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org"
      xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity3">
    <head>
        <title>文件上传demo</title>
    </head>
    <body>
       <form method="POST" enctype="multipart/form-data" action="/upload"> 
           <p>文件：<input type="file" name="file" /></p>
           <p><input type="submit" value="上传" /></p>
       </form>
    </body>
</html>

好啦，可以开始测试啦，打开浏览器，访问http://localhost:8080/file,选择文件进行上传。

二、多文件上传

1、对上传的文件做一些限制，在App.java进行编码配置：

            @Bean 
	    public MultipartConfigElement multipartConfigElement() { 
	        MultipartConfigFactory factory = new MultipartConfigFactory();
	        //设置文件大小限制 ,超了，页面会抛出异常信息，这时候就需要进行异常信息的处理了;
	        factory.setMaxFileSize("1024KB"); //KB,MB
	        // 设置总上传数据总大小
	        factory.setMaxRequestSize("1024KB");
	        //factory.setLocation("路径地址");
	        return factory.createMultipartConfig(); 
	    }

2、编写多文件上传controller

package com.gongh.controller;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;

@Controller
public class FileUploadController {
    
    @RequestMapping("/multiuploadfile")
    public String multiuploadfile(){
       return"/multiuploadfile";
    }
    
	
    
    /**
    * 多文件具体上传时间，主要是使用了MultipartHttpServletRequest和MultipartFile
    * @param request
    * @return
    */

   @RequestMapping(value="/multiupload", method= RequestMethod.POST) 
   @ResponseBody
   public String handleFileUpload(HttpServletRequest request){ 

       List<MultipartFile> files = ((MultipartHttpServletRequest)request).getFiles("file"); 
       MultipartFile file = null;
       BufferedOutputStream stream = null;
       for (int i =0; i< files.size(); ++i) { 
           file = files.get(i); 
           if (!file.isEmpty()) { 
               try { 
                   byte[] bytes = file.getBytes(); 
                   stream = 
                           new BufferedOutputStream(new FileOutputStream(new File(file.getOriginalFilename()))); 
                   stream.write(bytes); 
                   stream.close(); 
               } catch (Exception e) { 
                   stream =  null;
                   return "You failed to upload " + i + " => " + e.getMessage(); 
               } 
           } else { 
               return "You failed to upload " + i + " because the file was empty."; 
           } 
       } 

       return "upload successful"; 

   } 
}

3、编写multiuploadfile.html

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org"

      xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity3">

    <head>
        <title>多文件上传demo</title>
    </head>

    <body>
       <form method="POST" enctype="multipart/form-data" action="/multiupload"> 
           <p>文件1：<input type="file" name="file" /></p>
           <p>文件2：<input type="file" name="file" /></p>
           <p>文件3：<input type="file" name="file" /></p>
           <p><input type="submit" value="上传" /></p>
       </form>

    </body>

</html>

好啦，可以开始测试啦，打开浏览器，访问http://localhost:8080/multiuploadfile，选择文件进行上传。