java给图片添加水印

import java.awt.Color;

import java.awt.Graphics2D;

import java.awt.Image;

import java.awt.image.BufferedImage;

import java.io.FileOutputStream;

import javax.swing.ImageIcon;

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

import com.sun.image.codec.jpeg.JPEGEncodeParam;

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

public class WaterMark {

    /**

     * 给图片添加水印，另起画布，先画图片再画水印

     * 参数如下：

     *   filePath 需要添加水印的图片的路径

     *  markContent 水印的文字

     *   markContentColor 水印文字的颜色

     *   qualNum 图片质量

     */

public void createMark(String filePath, String markContent,Color markContentColor, float qualNum) {

  ImageIcon imgIcon = new ImageIcon(filePath);

  Image theImg = imgIcon.getImage();

  //图片大小

  int width = theImg.getWidth(null);

  int height = theImg.getHeight(null);

  

  BufferedImage bimage = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);

  Graphics2D g = bimage.createGraphics();

  g.setColor(markContentColor);

  g.setBackground(Color.white);

  g.drawImage(theImg, 0, 0, null);

  //g.drawString(markContent, width-markContent.length()*6 , height-10 ); // 添加水印的文字和设置水印文字出现的内容

  g.drawString(markContent, 100 , 100 );

  //释放绘图对象

        g.dispose();

        try {

         //输出新图片

FileOutputStream out = new FileOutputStream(filePath);

JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);

            JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(bimage);

            param.setQuality(qualNum, true);

            encoder.encode(bimage, param);

            out.close();

            

        } catch (Exception e) {}

    }

    //测试

    public static void main(String[] args) {

    

        WaterMark wm = new WaterMark();

        wm.createMark("d://map.jpg","http://img.china.alibaba.com/",Color.red,200f);

        

    }

}