Spring MVC 4 使用常规的fileupload上传文件（带源码）

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发布于 2021-08-27 15:27:43

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发布于 2021-08-27 15:27:43

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Spring MVC 4 文件上传下载 Hibernate+MySQL例子（带源码）

原文地址：http://websystique.com/springmvc/spring-mvc-4-file-upload-example-using-commons-fileupload/

本文将实现使用SpringMultipartResolver实现单个或者多文件上传.Spring提供内置multipart 支持用来处理web 应用中文件上传。

注意:multipart 是 enctype=”multipart/form-data”的内容.

简单预览

Spring使用MultiPartResolver接口实现文件上传.

1. 使用Apache Commons . Spring CommonsMultipartResolver 使用Apache Commons FileUpload 实现 MultipartResolver . 它需要apache 的commons-fileupload.jar 包. 虽然不针对Servlet 3但是Servlet 3.x容器中使用也没问题。
2. 要想用Servlet 3.0 multipart 请求需要配置[XML or JavaConfig]..
XML 设置, 你需要在 web.xml的"multipart-config" 节点配置DispatcherServlet. 如果是Annoataion/JavaConfig配置, 在DispatcherServlet 注册javax.servlet.MultipartConfigElement .或者使用 @MultipartConfig定义servlet.

本文主要用CommonsMultipartResolver . 下一篇文章使用Servlet 3.0 来实现文件上传.

步骤:

创建一个CommonsMultipartResolver类型的bean , 指明和文件上传相关的配置文件
在类路径包含 Apache Commons commons-fileupload.jar文件.
表单中要含有[enctype=”multipart/form-data”]
处理文件的input类型应该是 ‘file’

类似如下:

		....
			
		....

完整的例子

用到的技术和软件

Spring 4.2.0.RELEASE
Apache Commons fille-upload 1.3.1
validation-api 1.1.0.Final
Bootstrap v3.3.2
Maven 3
JDK 1.7
Tomcat 8.0.21
Eclipse JUNO Service Release 2

项目结构

在pom.xml文件中声明依赖

  4.0.0
  com.websystique.springmvc
  Spring4MVCFileUploadCommonsExample
  war
  1.0.0
  Spring4MVCFileUploadCommonsExample Maven Webapp
  http://maven.apache.org
  
  
    
		4.2.0.RELEASE
	

	
		
			org.springframework
			spring-webmvc
			${springframework.version}
		

		
			commons-fileupload
			commons-fileupload
			1.3.1
		

		
		
            javax.validation
            validation-api
            1.1.0.Final
        

		
		
			javax.servlet
			javax.servlet-api
			3.1.0
		
		
			javax.servlet
			jstl
			1.2
		
	


	
		
			
				
					org.apache.maven.plugins
					maven-compiler-plugin
					3.2
					
						1.7
						1.7
					
				
				
					org.apache.maven.plugins
					maven-war-plugin
					2.4
					
						src/main/webapp
						Spring4MVCFileUploadCommonsExample
						false
					
				
			
		

		Spring4MVCFileUploadCommonsExample

创建配置类

package com.websystique.springmvc.configuration;

import java.io.IOException;

import org.springframework.context.MessageSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.ResourceBundleMessageSource;
import org.springframework.web.multipart.commons.CommonsMultipartResolver;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.ViewResolverRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "com.websystique.springmvc")
public class HelloWorldConfiguration extends WebMvcConfigurerAdapter{

	@Bean(name="multipartResolver") 
	public CommonsMultipartResolver getResolver() throws IOException{
		CommonsMultipartResolver resolver = new CommonsMultipartResolver();
		
		//Set the maximum allowed size (in bytes) for each individual file.
		resolver.setMaxUploadSizePerFile(5242880);//5MB
		
		//You may also set other available properties.
		
		return resolver;
	}

	@Override
    public void configureViewResolvers(ViewResolverRegistry registry) {
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
        viewResolver.setViewClass(JstlView.class);
        viewResolver.setPrefix("/WEB-INF/views/");
        viewResolver.setSuffix(".jsp");
        registry.viewResolver(viewResolver);
    }
    
	@Bean
    public MessageSource messageSource() {
        ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
        messageSource.setBasename("messages");
        return messageSource;
    }
	
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/static/**").addResourceLocations("/static/");
    }

}

配置里面最重要的是 CommonsMultipartResolver Bean. 它是Apache Commons FileUpload里面的 MultipartResolver接口的实现。

你可以设置文件最大限制， headerEncoding 等，我们例子里只限制5M。

对应的XML配置形式：

            messages
        
    


    
        
            /WEB-INF/views/
        
        
            .jsp

创建模型类

Spring提供 org.springframework.web.multipart.MultipartFile 类代表上传的文件，提供getName(), getContentType(), getBytes(), getInputStream()等方法。

package com.websystique.springmvc.model;
 
import org.springframework.web.multipart.MultipartFile;
 
public class FileBucket {
 
    MultipartFile file;
     
    public MultipartFile getFile() {
        return file;
    }
 
    public void setFile(MultipartFile file) {
        this.file = file;
    }
}

包装类：

package com.websystique.springmvc.model;
 
import java.util.ArrayList;
import java.util.List;
 
public class MultiFileBucket {
 
    List files = new ArrayList();
     
    public MultiFileBucket(){
        files.add(new FileBucket());
        files.add(new FileBucket());
        files.add(new FileBucket());
    }
     
    public List getFiles() {
        return files;
    }
 
    public void setFiles(List files) {
        this.files = files;
    }
}

创建控制器类

package com.websystique.springmvc.controller;
 
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
 
import javax.validation.Valid;
 
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.util.FileCopyUtils;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.multipart.MultipartFile;
 
import com.websystique.springmvc.model.FileBucket;
import com.websystique.springmvc.model.MultiFileBucket;
import com.websystique.springmvc.util.FileValidator;
import com.websystique.springmvc.util.MultiFileValidator;
 
@Controller
public class FileUploadController {
 
    private static String UPLOAD_LOCATION="C:/mytemp/";
     
    @Autowired
    FileValidator fileValidator;
     
 
    @Autowired
    MultiFileValidator multiFileValidator;
 
     
    @InitBinder("fileBucket")
    protected void initBinderFileBucket(WebDataBinder binder) {
       binder.setValidator(fileValidator);
    }
 
 
    @InitBinder("multiFileBucket")
    protected void initBinderMultiFileBucket(WebDataBinder binder) {
       binder.setValidator(multiFileValidator);
    }
 
     
    @RequestMapping(value={"/","/welcome"}, method = RequestMethod.GET)
    public String getHomePage(ModelMap model) {
        return "welcome";
    }
 
    @RequestMapping(value="/singleUpload", method = RequestMethod.GET)
    public String getSingleUploadPage(ModelMap model) {
        FileBucket fileModel = new FileBucket();
        model.addAttribute("fileBucket", fileModel);
        return "singleFileUploader";
    }
 
    @RequestMapping(value="/singleUpload", method = RequestMethod.POST)
    public String singleFileUpload(@Valid FileBucket fileBucket, BindingResult result, ModelMap model) throws IOException {
 
        if (result.hasErrors()) {
            System.out.println("validation errors");
            return "singleFileUploader";
        } else {            
            System.out.println("Fetching file");
            MultipartFile multipartFile = fileBucket.getFile();
 
            //Now do something with file...
            FileCopyUtils.copy(fileBucket.getFile().getBytes(), new File(UPLOAD_LOCATION + fileBucket.getFile().getOriginalFilename()));
             
            String fileName = multipartFile.getOriginalFilename();
            model.addAttribute("fileName", fileName);
            return "success";
        }
    }
 
     
    @RequestMapping(value="/multiUpload", method = RequestMethod.GET)
    public String getMultiUploadPage(ModelMap model) {
        MultiFileBucket filesModel = new MultiFileBucket();
        model.addAttribute("multiFileBucket", filesModel);
        return "multiFileUploader";
    }
 
    @RequestMapping(value="/multiUpload", method = RequestMethod.POST)
    public String multiFileUpload(@Valid MultiFileBucket multiFileBucket, BindingResult result, ModelMap model) throws IOException {
 
         
        if (result.hasErrors()) {
            System.out.println("validation errors in multi upload");
            return "multiFileUploader";
        } else {            
            System.out.println("Fetching files");
            List fileNames= new ArrayList();
             
            //Now do something with file...
            for(FileBucket bucket : multiFileBucket.getFiles()){
                FileCopyUtils.copy(bucket.getFile().getBytes(), new File(UPLOAD_LOCATION + bucket.getFile().getOriginalFilename()));
                fileNames.add(bucket.getFile().getOriginalFilename());
            }
             
            model.addAttribute("fileNames", fileNames);
            return "multiSuccess";
        }
    }
     
     
     
}

Spring FileCopyUtils 工具类，可以将流从一个地方拷贝到目标文件夹。例子中目标目录是 C:/mytemp 所有文件将传到这里。

创建Validators类

package com.websystique.springmvc.util;
 
import org.springframework.stereotype.Component;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
 
import com.websystique.springmvc.model.FileBucket;
 
@Component
public class FileValidator implements Validator {
     
    public boolean supports(Class clazz) {
        return FileBucket.class.isAssignableFrom(clazz);
    }
 
    public void validate(Object obj, Errors errors) {
        FileBucket file = (FileBucket) obj;
         
        if(file.getFile()!=null){
            if (file.getFile().getSize() == 0) {
                errors.rejectValue("file", "missing.file");
            }
        }
    }
}

package com.websystique.springmvc.util;
 
import org.springframework.stereotype.Component;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
 
import com.websystique.springmvc.model.FileBucket;
import com.websystique.springmvc.model.MultiFileBucket;
 
@Component
public class MultiFileValidator implements Validator {
     
    public boolean supports(Class clazz) {
        return MultiFileBucket.class.isAssignableFrom(clazz);
    }
 
    public void validate(Object obj, Errors errors) {
        MultiFileBucket multiBucket = (MultiFileBucket) obj;
         
        int index=0;
         
        for(FileBucket file : multiBucket.getFiles()){
            if(file.getFile()!=null){
                if (file.getFile().getSize() == 0) {
                    errors.rejectValue("files["+index+"].file", "missing.file");
                }
            }
            index++;
        }
         
    }
}

messages.properties

missing.file= Please select a file.

创建视图

singleFileUploader.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

 

    
    Spring 4 MVC File Upload Example
    
    

 
 
    
        Spring 4 MVC File Upload Example 
        
         
            
                
                    Upload a file
                    
                        
                        
                            
                        
                    
                
            
     
            
                
                    
                
            
        
        Home

success.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>


    
    File Upload Success
    
    


    
        File  ${fileName} uploaded successfully.
        


        Home

multiFileUploader.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

 

    
    Spring 4 MVC File Multi Upload Example
    
    

 
 
    
        Spring 4 MVC Multi File Upload Example 
        
         
            
                
                
                    
                
            
            

            
                
                    
                
            
        
         
        

        Home

multiSuccess.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>


    
    File Upload Success
    
    


    
            
                File  ${fileName} uploaded successfully

            
            

        Home

welcome.jsp

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

 

    
    Spring 4 MVC File Upload Example
    
    


    
        Welcome to FileUploader Example
         
        Click on below links to see FileUpload in action.


         
        Single File Upload  OR  Multi File Upload

创建初始化类

package com.websystique.springmvc.configuration;
 
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
 
public class HelloWorldInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
  
 
    @Override
    protected Class[] getRootConfigClasses() {
        return new Class[] { HelloWorldConfiguration.class };
    }
   
    @Override
    protected Class[] getServletConfigClasses() {
        return null;
    }
   
    @Override
    protected String[] getServletMappings() {
        return new String[] { "/" };
    }
  
 }