java实现给图片添加水印

 package michael.io.image;   

 import java.awt.AlphaComposite;
 import java.awt.Graphics2D;
 import java.awt.Image;
 import java.awt.RenderingHints;
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.InputStream;
 import java.io.OutputStream;   

 import javax.imageio.ImageIO;
 import javax.swing.ImageIcon;   

 import com.sun.image.codec.jpeg.JPEGCodec;
 import com.sun.image.codec.jpeg.JPEGImageDecoder;
 import com.sun.image.codec.jpeg.JPEGImageEncoder;   

 /**
  * 图片水印
  * @blog http://sjsky.iteye.com
  * @author Michael
  */
 public class ImageMarkLogoByIcon {   

     /**
      * @param args
      */
     public static void main(String[] args) {
         String srcImgPath = "d:/test/michael/myblog_01.png";
         String iconPath = "d:/test/michael/blog_logo.png";
         String targerPath = "d:/test/michael/img_mark_icon.jpg";
         String targerPath2 = "d:/test/michael/img_mark_icon_rotate.jpg";
         // 给图片添加水印
         ImageMarkLogoByIcon.markImageByIcon(iconPath, srcImgPath, targerPath);
         // 给图片添加水印,水印旋转-45
         ImageMarkLogoByIcon.markImageByIcon(iconPath, srcImgPath, targerPath2,
                 -45);   

     }   

     /**
      * 给图片添加水印
      * @param iconPath 水印图片路径
      * @param srcImgPath 源图片路径
      * @param targerPath 目标图片路径
      */
     public static void markImageByIcon(String iconPath, String srcImgPath,
             String targerPath) {
         markImageByIcon(iconPath, srcImgPath, targerPath, null);
     }   

     /**
      * 给图片添加水印、可设置水印图片旋转角度
      * @param iconPath 水印图片路径
      * @param srcImgPath 源图片路径
      * @param targerPath 目标图片路径
      * @param degree 水印图片旋转角度
      */
     public static void markImageByIcon(String iconPath, String srcImgPath,
             String targerPath, Integer degree) {
         OutputStream os = null;
         try {
             Image srcImg = ImageIO.read(new File(srcImgPath));   

             BufferedImage buffImg = new BufferedImage(srcImg.getWidth(null),
                     srcImg.getHeight(null), BufferedImage.TYPE_INT_RGB);   

             // 得到画笔对象
             // Graphics g= buffImg.getGraphics();
             Graphics2D g = buffImg.createGraphics();   

             // 设置对线段的锯齿状边缘处理
             g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
                     RenderingHints.VALUE_INTERPOLATION_BILINEAR);   

             g.drawImage(srcImg.getScaledInstance(srcImg.getWidth(null), srcImg
                     .getHeight(null), Image.SCALE_SMOOTH), 0, 0, null);   

             if (null != degree) {
                 // 设置水印旋转
                 g.rotate(Math.toRadians(degree),
                         (double) buffImg.getWidth() / 2, (double) buffImg
                                 .getHeight() / 2);
             }   

             // 水印图象的路径 水印一般为gif或者png的，这样可设置透明度
             ImageIcon imgIcon = new ImageIcon(iconPath);   

             // 得到Image对象。
             Image img = imgIcon.getImage();   

             float alpha = 0.5f; // 透明度
             g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
                     alpha));   

             // 表示水印图片的位置
             g.drawImage(img, 150, 300, null);   

             g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER));   

             g.dispose();   

             os = new FileOutputStream(targerPath);   

             // 生成图片
             ImageIO.write(buffImg, "JPG", os);   

             System.out.println("图片完成添加Icon印章。。。。。。");
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             try {
                 if (null != os)
                     os.close();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
     }
 }