对于我一个菜鸟来说，以前一直对io这块不熟悉，现在业务需求要求对富文本中的图片添加水印，在百度上查了都不是适合我的项目，只能自己研究，研究了俩天终于写了出来，现在我把我的方法写出来，供大家查阅

1.因为是在SpringMVC里面写的，SpringMVC提供了一个MultipartFile类，直接上代码

/*** ueditor上传单文件* @param request* @return*/
@RequestMapping(value = "ueditorUpFile")
public
@ResponseBody
UeditorFormat ueditorUpFile(HttpServletRequest request){MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;// 从config.json中取得上传文件的IDMultipartFile upfile = multipartRequest.getFile("upfile");try {InputStream inputStream = upfile.getInputStream();} catch (IOException e) {e.printStackTrace();}//获取项目根路径String realpath= request.getSession().getServletContext().getRealPath("/");if(Objects.nonNull(upfile)){//这个是我的项目类，没有关系SysFile file = new SysFile();file.setCreateDate(new Date());file.setName(upfile.getOriginalFilename());file.setRandomName(IdGen.uuid());file.setStatus(SysFile.TEMP_FILE);file.setSuffix(file.getName().substring(file.getName().lastIndexOf(".")));file.setSize(upfile.getSize());try {//上传到服务器的路径，没有关系String filepath = sysFileService.genFilePath(2, file.getRandomName(), file.getSuffix());//获取上传的图片File tarfile = new File(realpath+upfile.getOriginalFilename());try {//把内存图片写入磁盘中upfile.transferTo(tarfile);if (!tarfile.getParentFile().exists()) {tarfile.getParentFile().mkdir();}try {//添加水印WaterMarkGenerate.generateWithImageMark(tarfile,realpath+File.separator+"upload"+File.separator+file.getRandomName()+file.getSuffix(),realpath+File.separator+"static"+File.separator+"images"+File.separator+"watermark.png");} catch (Exception e) {e.printStackTrace();}//获取添加水印后的图片File newFile = new File(realpath+File.separator+"upload"+File.separator+file.getRandomName()+file.getSuffix());FileInputStream input = new FileInputStream(newFile);MultipartFile multipartFile = new MockMultipartFile("file",file.getName(), "text/plain", IOUtils.toByteArray(input));upfile = multipartFile;} catch (IOException e) {e.printStackTrace();}//水印图片保存到服务器file = sysFileService.saveFile(file, upfile, filepath);return UeditorFormat.parseSysFile(file);} catch (FileUploadFailException e) {e.printStackTrace();UeditorFormat uf = new UeditorFormat();uf.setState("文件上传失败");uf.setTitle(upfile.getOriginalFilename());return uf;}} else {UeditorFormat uf = new UeditorFormat();uf.setState("文件上传失败，上传的文件为空！");uf.setTitle(upfile.getOriginalFilename());return uf;}
}

这个添加水印的类也是我从网上找的，特别好用，亲测，现在分享给大家

public class WaterMarkGenerate {private static final String FONT_FAMILY="微软雅黑";//字体private static final int FONT_STYLE=Font.BOLD;//字体加粗private static final int FONT_SIZE=24;//字体大小private static final float ALPHA=0.7F;//水印透明度private static final int LOGO_WIDTH=200;//图片水印大小//添加文字水印/*tarPath:图片保存路径*contents:文字水印内容* */public static void generateWithTextMark(File srcFile,String tarPath,String contents) throws Exception{Image srcImage=ImageIO.read(srcFile);int width=srcImage.getWidth(null);int height=srcImage.getHeight(null);BufferedImage tarBuffImage=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);Graphics2D g=tarBuffImage.createGraphics();g.drawImage(srcImage, 0, 0, width,height,null);//计算int strWidth=FONT_SIZE*getTextLength(contents);int strHeight=FONT_SIZE;//水印位置
//      int x=width-strWidth;
//      int y=height-strHeight;int x=0,y=0;//设置字体和水印透明度g.setFont(new Font(FONT_FAMILY,FONT_STYLE,FONT_SIZE));g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,ALPHA));
//      g.drawString(contents, x, y);//旋转图片g.rotate(Math.toRadians(-30),width/2,height/2);while(x < width*1.5){y = -height/2;while(y < height*1.5){g.drawString(contents,x,y);y += strHeight + 50;}x += strWidth + 50; //水印之间的间隔设为50}g.dispose();JPEGImageEncoder en = JPEGCodec.createJPEGEncoder(new FileOutputStream(tarPath));en.encode(tarBuffImage);}//添加图片水印/** tarPath:图片保存路径* logoPath:logo文件路径* */public static void generateWithImageMark(File srcFile,String tarPath,String logoPath) throws Exception{Image srcImage=ImageIO.read(srcFile);int width=srcImage.getWidth(null);int height=srcImage.getHeight(null);//创建一个不带透明色的BufferedImage对象BufferedImage tarBuffImage=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);Graphics2D g=tarBuffImage.createGraphics();g.drawImage(srcImage, 0, 0, width,height,null);Image logoImage= ImageIO.read(new File(logoPath));int logoWidth=LOGO_WIDTH;int logoHeight=(LOGO_WIDTH*logoImage.getHeight(null))/logoImage.getWidth(null);int x=width-logoWidth;int y=height-logoHeight;g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,ALPHA));g.drawImage(logoImage, x, y, logoWidth, logoHeight, null);g.dispose();JPEGImageEncoder en = JPEGCodec.createJPEGEncoder(new FileOutputStream(tarPath));en.encode(tarBuffImage);}//文本长度的处理：文字水印的中英文字符的宽度转换public static int getTextLength(String text){int length = text.length();for(int i=0;i<text.length();i++){String s = String.valueOf(text.charAt(i));if(s.getBytes().length>1){  //中文字符length++;}}length = length%2 == 0?length/2:length/2+1;  //中文和英文字符的转换return length;}
}