基于SpringBoot实现图片上传与显示

<dependencies> <!--FreeMarker模板视图依赖-->    <dependency>      <groupId>org.springframework.boot</groupId>      <artifactId>spring-boot-starter-freemarker</artifactId>    </dependency>    <dependency>      <groupId>org.springframework.boot</groupId>      <artifactId>spring-boot-starter-web</artifactId>    </dependency>    <dependency>      <groupId>org.springframework.boot</groupId>      <artifactId>spring-boot-starter-test</artifactId>      <scope>test</scope>    </dependency></dependencies>

server.port=8102### FreeMarker 配置spring.freemarker.allow-request-override=false#Enable template caching.启用模板缓存。spring.freemarker.cache=falsespring.freemarker.check-template-location=truespring.freemarker.charset=UTF-8spring.freemarker.content-type=text/htmlspring.freemarker.expose-request-attributes=falsespring.freemarker.expose-session-attributes=falsespring.freemarker.expose-spring-macro-helpers=false#设置面板后缀spring.freemarker.suffix=.ftl# 设置单个文件最大内存multipart.maxFileSize=50Mb# 设置所有文件最大内存multipart.maxRequestSize=50Mb# 自定义文件上传路径web.upload-path=E:/Develop/Files/Photos/

package com.wu.demo.fileupload.demo.util;public class FileNameUtils {  /**   * 获取文件后缀   * @param fileName   * @return   */  public static String getSuffix(String fileName){    return fileName.substring(fileName.lastIndexOf("."));  }  /**   * 生成新的文件名   * @param fileOriginName 源文件名   * @return   */  public static String getFileName(String fileOriginName){    return UUIDUtils.getUUID() + FileNameUtils.getSuffix(fileOriginName);  }}

import java.util.UUID;/** * 生成文件名 */public class UUIDUtils {  public static String getUUID(){    return UUID.randomUUID().toString().replace("-", "");  }}

package com.wu.demo.fileupload.demo.util;import org.springframework.web.multipart.MultipartFile;import java.io.File;import java.io.IOException;/** * 文件上传工具包 */public class FileUtils {  /**   *   * @param file 文件   * @param path 文件存放路径   * @param fileName 源文件名   * @return   */  public static boolean upload(MultipartFile file, String path, String fileName){    // 生成新的文件名    //String realPath = path + "/" + FileNameUtils.getFileName(fileName);    //使用原文件名    String realPath = path + "/" + fileName;    File dest = new File(realPath);    //判断文件父目录是否存在    if(!dest.getParentFile().exists()){      dest.getParentFile().mkdir();    }    try {      //保存文件      file.transferTo(dest);      return true;    } catch (IllegalStateException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return false;    } catch (IOException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return false;    }  }}

package com.wu.demo.fileupload.demo.controller;import com.wu.demo.fileupload.demo.util.FileUtils;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.factory.annotation.Value;import org.springframework.core.io.ResourceLoader;import org.springframework.http.ResponseEntity;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.multipart.MultipartFile;import javax.servlet.http.HttpServletResponse;import java.util.Map;@Controllerpublic class TestController {  private final ResourceLoader resourceLoader;  @Autowired  public TestController(ResourceLoader resourceLoader) {    this.resourceLoader = resourceLoader;  }  @Value("${web.upload-path}")  private String path;  /**   * 跳转到文件上传页面   * @return   */  @RequestMapping("test")  public String toUpload(){    return "test";  }  /**   *   * @param file 要上传的文件   * @return   */  @RequestMapping("fileUpload")  public String upload(@RequestParam("fileName") MultipartFile file, Map<String, Object> map){    // 要上传的目标文件存放路径    String localPath = "E:/Develop/Files/Photos";    // 上传成功或者失败的提示    String msg = "";    if (FileUtils.upload(file, localPath, file.getOriginalFilename())){      // 上传成功，给出页面提示      msg = "上传成功！";    }else {      msg = "上传失败！";    }    // 显示图片    map.put("msg", msg);    map.put("fileName", file.getOriginalFilename());    return "forward:/test";  }  /**   * 显示单张图片   * @return   */  @RequestMapping("show")  public ResponseEntity showPhotos(String fileName){    try {      // 由于是读取本机的文件，file是一定要加上的， path是在application配置文件中的路径      return ResponseEntity.ok(resourceLoader.getResource("file:" + path + fileName));    } catch (Exception e) {      return ResponseEntity.notFound().build();    }  }}

<!DOCTYPE html><head>  <meta charset="UTF-8" />  <title>图片上传Demo</title></head><body><h1 >图片上传Demo</h1><form action="fileUpload" method="post" enctype="multipart/form-data">  <p>选择文件: <input type="file" name="fileName"/></p>  <p><input type="submit" value="提交"/></p></form><#--判断是否上传文件--><#if msg??>  <span>${msg}</span><br><#else >  <span>${msg!("文件未上传")}</span><br></#if><#--显示图片，一定要在img中的src发请求给controller，否则直接跳转是乱码--><#if fileName??><img src="/show?fileName=${fileName}" style="width: 200px"/><#else><img src="/show" style="width: 100px"/></#if></body></html>