Java水印工具类

来源：http://shensy.iteye.com/blog/1614153

package com.dxy.image;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;

import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
public class ImageAddWaterMark {
       
        public static void main(String[] args) {
                File originImgFile = new File("D:/image/1.jpg");
                File watermarkImgFile = new File("D:/image/2.jpg");
                File targetImgFile = new File("D:/image/3.jpg");
                addWatermark(originImgFile,watermarkImgFile,targetImgFile);
        }
       
        /**
     * 图片上加水印
     * @param originImgFile 原图
     * @param watermarkImgFile 水印图
     * @param targetImgFile 输出文件
     */
    public static File addWatermark(File originImgFile,File watermarkImgFile,File targetImgFile){
        FileOutputStream fileOutputStream = null;
        try {
            //原图
            Image originImage = ImageIO.read(originImgFile);
            int originWidth = originImage.getWidth(null);//原图长
            int originHeight = originImage.getHeight(null);//原图宽
            //表示一个图像,它具有合成整数像素的 8位 RGB颜色分量.(以原图的长宽作为新图片的长宽)
            BufferedImage image = new BufferedImage(originWidth,originHeight,BufferedImage.TYPE_INT_RGB);
            Graphics g = image.createGraphics();//获取Graphics以渲染BufferedImage
            g.drawImage(originImage,0,0,originWidth,originHeight,null);//从渲染原图
           
            //水印图
            Image waterMarkImage = ImageIO.read(watermarkImgFile);
            int waterMarkWidth = waterMarkImage.getWidth(null);//水印图长
            int waterMarkHeight = waterMarkImage.getHeight(null);//水印图宽
            //在原图指定位置渲染水印图(此处设置为右下角)
            g.drawImage(waterMarkImage,(originWidth-waterMarkWidth),(originHeight-waterMarkHeight),waterMarkWidth,waterMarkHeight,null);
            //释放此图形的上下文以及它使用的所有系统资源
            g.dispose();
           
            ImageWriter imgWrier = ImageIO.getImageWritersByFormatName("jpg").next();
            imgWrier.reset();
           
            fileOutputStream = new FileOutputStream(targetImgFile);//目标文件
            imgWrier.setOutput(ImageIO.createImageOutputStream(fileOutputStream));
            //IIOImage:聚集图像、缩略（预览）图像集和表示与图像关联的元数据对象的简单容器类
            imgWrier.write(new IIOImage(image,null,null));
            fileOutputStream.flush();
            return targetImgFile;
        }catch(Exception e){
                e.printStackTrace();
        }finally {
                try{
                        if(fileOutputStream!=null) fileOutputStream.close();
                }catch(Exception e){
                        e.printStackTrace();
                }
        }
        return null;
    }

}