java实现上传图片并压缩图片大小功能

 <!-- 图片缩略图 --> <dependency> <groupId>net.coobird</groupId> <artifactId>thumbnailator</artifactId> <version>0.4.8</version></dependency>

//按指定大小把图片进行缩和放（会遵循原图高宽比例）  //此处把图片压成400×500的缩略图Thumbnails.of(fromPic).size(400,500).toFile(toPic);//变为400*300,遵循原图比例缩或放到400*某个高度

//按照比例进行缩小和放大Thumbnails.of(fromPic).scale(0.2f).toFile(toPic);//按比例缩小Thumbnails.of(fromPic).scale(2f);//按比例放大

//图片尺寸不变，压缩图片文件大小outputQuality实现,参数1为最高质量Thumbnails.of(fromPic).scale(1f).outputQuality(0.25f).toFile(toPic);

/** *  * @Description:保存图片并且生成缩略图 * @param imageFile 图片文件 * @param request 请求对象 * @param uploadPath 上传目录 * @return */ public static BaseResult uploadFileAndCreateThumbnail(MultipartFile imageFile,HttpServletRequest request,String uploadPath) { if(imageFile == null ){ return new BaseResult(false, "imageFile不能为空"); }  if (imageFile.getSize() >= 10*1024*1024) { return new BaseResult(false, "文件不能大于10M"); } String uuid = UUID.randomUUID().toString();  String fileDirectory = CommonDateUtils.date2string(new Date(), CommonDateUtils.YYYY_MM_DD);  //拼接后台文件名称 String pathName = fileDirectory + File.separator + uuid + "."  + FilenameUtils.getExtension(imageFile.getOriginalFilename()); //构建保存文件路劲 //2016-5-6 yangkang 修改上传路径为服务器上  String realPath = request.getServletContext().getRealPath("uploadPath"); //获取服务器绝对路径 linux 服务器地址 获取当前使用的配置文件配置 //String urlString=PropertiesUtil.getInstance().getSysPro("uploadPath"); //拼接文件路劲 String filePathName = realPath + File.separator + pathName; log.info("图片上传路径："+filePathName); //判断文件保存是否存在 File file = new File(filePathName); if (file.getParentFile() != null || !file.getParentFile().isDirectory()) { //创建文件 file.getParentFile().mkdirs(); }  InputStream inputStream = null; FileOutputStream fileOutputStream = null; try { inputStream = imageFile.getInputStream(); fileOutputStream = new FileOutputStream(file); //写出文件 //2016-05-12 yangkang 改为增加缓存// IOUtils.copy(inputStream, fileOutputStream); byte[] buffer = new byte[2048]; IOUtils.copyLarge(inputStream, fileOutputStream, buffer); buffer = null; } catch (IOException e) { filePathName = null; return new BaseResult(false, "操作失败", e.getMessage()); } finally { try { if (inputStream != null) {  inputStream.close(); } if (fileOutputStream != null) {  fileOutputStream.flush();  fileOutputStream.close(); } } catch (IOException e) { filePathName = null; return new BaseResult(false, "操作失败", e.getMessage()); }  }   // String fileId = FastDFSClient.uploadFile(file, filePathName);  /** * 缩略图begin */  //拼接后台文件名称 String thumbnailPathName = fileDirectory + File.separator + uuid + "small."   + FilenameUtils.getExtension(imageFile.getOriginalFilename()); //added by yangkang 2016-3-30 去掉后缀中包含的.png字符串  if(thumbnailPathName.contains(".png")){ thumbnailPathName = thumbnailPathName.replace(".png", ".jpg"); } long size = imageFile.getSize(); double scale = 1.0d ; if(size >= 200*1024){ if(size > 0){ scale = (200*1024f) / size ; } }   //拼接文件路劲 String thumbnailFilePathName = realPath + File.separator + thumbnailPathName; try { //added by chenshun 2016-3-22 注释掉之前长宽的方式，改用大小// Thumbnails.of(filePathName).size(width, height).toFile(thumbnailFilePathName); if(size < 200*1024){ Thumbnails.of(filePathName).scale(1f).outputFormat("jpg").toFile(thumbnailFilePathName); }else{ Thumbnails.of(filePathName).scale(1f).outputQuality(scale).outputFormat("jpg").toFile(thumbnailFilePathName); }  } catch (Exception e1) { return new BaseResult(false, "操作失败", e1.getMessage()); } /** * 缩略图end */  Map<String, Object> map = new HashMap<String, Object>(); //原图地址 map.put("originalUrl", pathName); //缩略图地址 map.put("thumbnailUrl", thumbnailPathName); return new BaseResult(true, "操作成功", map); }

 /** * 根据key从gzt.properties配置文件获取配置信息  * @param key 键值 * @return */ public String getSysPro(String key){ return getSysPro(key, null); } /** * 根据key从gzt.properties配置文件获取配置信息  * @param key 键值 * @param defaultValue 默认值 * @return */ public String getSysPro(String key,String defaultValue){ return getValue("spring/imageserver-"+System.getProperty("spring.profiles.active")+".properties", key, defaultValue); }

//获取服务器绝对路径 linux 服务器地址 String urlString=PropertiesUtil.getInstance().getSysPro("uploadPath");

package com.xyz.imageserver.common.properties;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.util.Properties;import java.util.concurrent.ConcurrentHashMap;/** *  * @ClassName PropertiesUtil.java  * @Description 系统配置工具类 * @author caijy * @date 2015年6月9日 上午10:50:38 * @version 1.0.0 */public class PropertiesUtil { private Logger logger = LoggerFactory.getLogger(PropertiesUtil.class); private ConcurrentHashMap<String, Properties> proMap; private PropertiesUtil() { proMap = new ConcurrentHashMap<String, Properties>(); } private static PropertiesUtil instance = new PropertiesUtil(); /** * 获取单例对象 * @return */ public static PropertiesUtil getInstance() { return instance; }  /** * 根据key从gzt.properties配置文件获取配置信息  * @param key 键值 * @return */ public String getSysPro(String key){ return getSysPro(key, null); } /** * 根据key从gzt.properties配置文件获取配置信息  * @param key 键值 * @param defaultValue 默认值 * @return */ public String getSysPro(String key,String defaultValue){ return getValue("spring/imageserver-"+System.getProperty("spring.profiles.active")+".properties", key, defaultValue); } /** * 从配置文件中获取对应key值 * @param fileName 配置文件名 * @param key key值 * @param defaultValue 默认值 * @return */ public String getValue(String fileName,String key,String defaultValue){ String val = null; Properties properties = proMap.get(fileName); if(properties == null){ InputStream inputStream = PropertiesUtil.class.getClassLoader().getResourceAsStream(fileName); try {  properties = new Properties(); properties.load(new InputStreamReader(inputStream,"UTF-8")); proMap.put(fileName, properties); val = properties.getProperty(key,defaultValue); } catch (IOException e) { logger.error("getValue",e); }finally{ try {  if (inputStream != null) {    inputStream.close();  } } catch (IOException e1) {  logger.error(e1.toString()); } } }else{ val = properties.getProperty(key,defaultValue); } return val; }}