package com.bizzan.bitrade.util;

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.jpg";

		String waterFilePath = "D://img//vip.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), 65, 65, 1.0f);

// 输出水印图片

		newImageUtils.generateWaterFile(buffImg, saveFilePath);

	}

}