@Service
public?class?ThumbnailService?{
????public?static?final?int?WIDTH??=?100;
????public?static?final?int?HEIGHT?=?100;

????//使用類庫
????public?String?thumbnail(MultipartFile?file,String?uploadPath,?String?realUploadPath){
????????String?imgName?=?"thum_"+file.getOriginalFilename();
????????String?des?=?realUploadPath+"/"+imgName;
????????try?{
????????????Thumbnails.of(file.getInputStream()).size(WIDTH,HEIGHT).toFile(des);
????????}catch?(Exception?e){
????????????e.printStackTrace();
????????}
????????return?uploadPath+"/"+imgName;
????}

????//使用java?awt
????public?String?awt(MultipartFile?file,String?uploadPath,?String?realUploadPath){
????????OutputStream?os?=?null;
????????String?imgName?=?"thum_"+file.getOriginalFilename();
????????String?des?=?realUploadPath+"/"+imgName;
????????try?{
????????????os?=?new?FileOutputStream(des);
????????????Image?image?=?ImageIO.read(file.getInputStream());
????????????int?width?=?image.getWidth(null);//原圖寬
????????????int?height?=?image.getHeight(null);//原圖高
????????????int?rate1?=?width/WIDTH;//縮略圖寬比例
????????????int?rate2?=?height/HEIGHT;//縮略圖高比例
????????????int?rate?=?0;
????????????if(rate1?>?rate2){//寬度縮略比例大于高度縮略比例，使用寬度縮略比例
????????????????rate?=?rate1;
????????????}else?{
????????????????rate?=?rate2;
????????????}
????????????//計算縮略圖最終的寬度和高度
????????????int?newWidth?=?width/rate;
????????????int?newHeight?=?height/rate;
????????????BufferedImage?bufferedImage?=?new?BufferedImage(newWidth,newHeight,BufferedImage.TYPE_INT_RGB);
????????????bufferedImage.getGraphics().drawImage(image.getScaledInstance(newWidth,newHeight,image.SCALE_SMOOTH),0,0,null);
????????????String?imageType?=?file.getContentType().substring(file.getContentType().indexOf("/")+1);
????????????ImageIO.write(bufferedImage,imageType,os);
????????}catch?(Exception?e){
????????????e.printStackTrace();
????????}finally?{
????????????if(os!=null){
????????????????try?{
????????????????????os.close();
????????????????}catch?(Exception?e){
????????????????????e.printStackTrace();
????????????????}
????????????}
????????}
????????return?uploadPath+"/"+imgName;
????}
}