图片叠加效果Java代码实现

import java.awt.AlphaComposite;import java.awt.Graphics2D;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import javax.imageio.ImageIO;public class NewImageUtils {  /**   *    * @Title: 构造图片   * @Description: 生成水印并返回java.awt.image.BufferedImage   * @param file   *      源文件(图片)   * @param waterFile   *      水印文件(图片)   * @param x   *      距离右下角的X偏移量   * @param y   *      距离右下角的Y偏移量   * @param alpha   *      透明度, 选择值从0.0~1.0: 完全透明~完全不透明   * @return BufferedImage   * @throws IOException   */  public static BufferedImage watermark(File file, File waterFile, int x, int y, float alpha) throws IOException {    // 获取底图    BufferedImage buffImg = ImageIO.read(file);    // 获取层图    BufferedImage waterImg = ImageIO.read(waterFile);    // 创建Graphics2D对象，用在底图对象上绘图    Graphics2D g2d = buffImg.createGraphics();    int waterImgWidth = waterImg.getWidth();// 获取层图的宽度    int waterImgHeight = waterImg.getHeight();// 获取层图的高度    // 在图形和图像中实现混合和透明效果    g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));    // 绘制    g2d.drawImage(waterImg, x, y, waterImgWidth, waterImgHeight, null);    g2d.dispose();// 释放图形上下文使用的系统资源    return buffImg;  }  /**   * 输出水印图片   *    * @param buffImg   *      图像加水印之后的BufferedImage对象   * @param savePath   *      图像加水印之后的保存路径   */  private void generateWaterFile(BufferedImage buffImg, String savePath) {    int temp = savePath.lastIndexOf(".") + 1;    try {      ImageIO.write(buffImg, savePath.substring(temp), new File(savePath));    } catch (IOException e1) {      e1.printStackTrace();    }  }  /**   *    * @param args   * @throws IOException   *       IO异常直接抛出了   * @author bls   */  public static void main(String[] args) throws IOException {    String sourceFilePath = "D://img//di.png";    String waterFilePath = "D://img//ceng.png";    String saveFilePath = "D://img//new.png";    NewImageUtils newImageUtils = new NewImageUtils();    // 构建叠加层    BufferedImage buffImg = NewImageUtils.watermark(new File(sourceFilePath), new File(waterFilePath), 0, 0, 1.0f);    // 输出水印图片    newImageUtils.generateWaterFile(buffImg, saveFilePath);  }}