java之springmvc图片上传

客官°小女子只卖身不卖艺 2022-09-21 05:58 128阅读 0赞

图片上传功能是比较常用的技术，接触的两个项目都被项目经理要求写图片上传功能。

并且如果项目要求图片上传，一般紧随其后的还有下载和删除。

用到的东西还不一样

第一个项目是:使用springmvc完成图片上传

第二个项目是:使用struts2完成图片上传

第一个项目已经上线运行，保存实现便于日后参考，作为工具保存。

spring-selevet.xml

CommonsMultipartResolver 这是一个上传文件的分解器，主要的作用是配置文件上传的一些属性
    1.配置文件的编码方式 defaultEncoding
    2.配置文件最大值     maxUploadSize
    3.配置缓存           maxInMemorySize

注意：在这个bean中id一定要叫multipartResolver,否则会报错误。

上传文件需要的两个jar文件

commons-fileupload-1.2.2.jar  
    commons-io-1.3.2.jar

html：

Action:

package com.eznext.modul.telpipe.controller;
    
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.OutputStream;
    import java.security.Principal;
    
    import javax.servlet.http.HttpServletRequest;  
    import javax.servlet.http.HttpServletResponse;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.ModelMap;
    
    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.multipart.MultipartFile;
    
    import com.eznext.core.web.ActionResult;
    import com.eznext.modul.telpipe.service.FileService;
    
    import javax.activation.MimetypesFileTypeMap;
    
    @Controller 
    @RequestMapping("/file")
    public class FileAction {
    
    	private static Logger logger = LoggerFactory
    			.getLogger(FileAction.class);
    	
    	private int BUFFER_SIZE = 4096;
    	@Autowired
    	private FileService fileService;
    	
    	@ResponseBody
    	@RequestMapping(value = "upload")  
    	public ActionResult upload(@RequestParam("cate") String category, @RequestParam("file") MultipartFile file, HttpServletRequest request, ModelMap model) {  
    		  
    		//保存  
    		try { 
    			String fileName = this.fileService.getFilePath(category, file.getOriginalFilename());
    			String path = this.fileService.resolveToPhysicalFileName(fileName);
    			File targetFile = new File(path);  
    			if(!targetFile.exists()){  
    				targetFile.mkdirs();  
    			}  
    			file.transferTo(targetFile);
    			return ActionResult.Succeed(fileName);
    		} catch (Exception e) {  
    			logger.warn("", e);
    			return ActionResult.Failed(e);
    		}  		
    	}
    	
    	@RequestMapping(value = "req", method = RequestMethod.GET)
    	public void download(@RequestParam("f") String filename,
    			Principal principal, HttpServletResponse response) {
    		try {			
    			response.setHeader("Content-disposition", "attachment; filename=" + filename);
    			String physicalFilename = this.fileService.resolveToPhysicalFileName(filename);
    			File file = new File(physicalFilename);
    			String contentType = new MimetypesFileTypeMap().getContentType(file);
    			response.setContentType(contentType);
    			OutputStream outStream = response.getOutputStream();
    			byte[] buffer = new byte[BUFFER_SIZE];
    			FileInputStream fs = new FileInputStream(file);
    			int len = 0;
    			while((len = fs.read(buffer, 0, BUFFER_SIZE)) > 0){
    				outStream.write(buffer, 0, len);
    			}
    			fs.close();
    			outStream.flush();
    			outStream.close();
    			
    		} catch (Exception ex) {
    			logger.warn("product_download", ex);
    		}
    
    	}
    	
    	@RequestMapping(value = "del", method = RequestMethod.GET)
    	public ActionResult delete(@RequestParam("f") String filename,
    			Principal principal, HttpServletResponse response) {
    		try {
    			this.fileService.deleteFile(filename);
    			return ActionResult.Succeed();
    		} catch (Exception ex) {
    			logger.warn("product_download", ex);
    			return ActionResult.Failed(ex);
    		}
    
    	}
    }

抽个时间对以上代码进行详细解析，欧洲杯，NBA总决赛这几天都有，忙不过来了都。