ImgCutTools.java

package com.jshoperx.action.backstage.utils;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;

import org.apache.commons.io.IOUtils;

/**
* Created with sdywcd@gmail.com
* Author:sdywcd@gmail.com
* Date:15/7/23
* Time:下午4:04
* Note:图片裁剪工具类
**/
public class ImgCutTools {
	private static String[] imgExts = new String[] { ".jpeg", ".jpg", ".gif",".png" };
	public static boolean checkIsImg(String extName){
		boolean isImg = false;
		String en = extName;
		for (int i = 0; i < imgExts.length; i++) {
			if (en.equalsIgnoreCase(imgExts[i])) {
				isImg = true;
				break;
			}
		}
		return isImg;
	}
	public static String compressImages(String needCutImgPath,
			String targetSavePath, int width, int height) throws IOException {
		File file = new File(needCutImgPath);
		if (!file.exists()) {
			throw new IOException("图片不存在:" + needCutImgPath);
		}
		// 截取文件名称
		String fileName = file.getName();
		// 文件后缀
		String extName = null;
		// 新文件名
		String newFileName = null;
		// 图片类型
		String formatName = null;
		//压缩后的图片路径
		String compressFilePath=null;
		if (width != 0 && height != 0) {
			if (fileName.lastIndexOf(".") >= 0) {
				extName = fileName.substring(fileName.lastIndexOf("."));
				fileName = fileName.substring(0, fileName.lastIndexOf("."));
				formatName = extName.substring(1, extName.length());
			}
			//缩略图名称
			newFileName = fileName + "_" + String.valueOf(width) + "_"
					+ String.valueOf(height) + extName;
			compressFilePath=targetSavePath+newFileName;
			copyImageFile(file, compressFilePath);
			BufferedImage bufferedImage = ImageIO.read(file);
			BufferedImage zoomImage = compress(bufferedImage, width, height);
			boolean isWriteOK=ImageIO.write(zoomImage, formatName, new File(targetSavePath
					+ newFileName));
			if(isWriteOK){
				return compressFilePath;
			}
		}
		return compressFilePath;
	}

	/**
	 * 压缩图片
	 * 
	 * @param bufferedImage
	 * @param width
	 * @param height
	 * @return
	 */
	private static BufferedImage compress(BufferedImage bufferedImage,
			int width, int height) {
		BufferedImage compressImage = new BufferedImage(width, height,
				bufferedImage.getType());
		Image image = bufferedImage.getScaledInstance(width, height,
				Image.SCALE_SMOOTH);
		Graphics graphics = compressImage.getGraphics();
		graphics.setColor(Color.WHITE);
		graphics.drawImage(image, 0, 0, null);
		return compressImage;
	}

	/**
	 * 复制图片文件进行缩略图处理
	 * @param oldFile
	 * @param newFilePath
	 * @throws IOException
	 */
	private static void copyImageFile(File oldFile,String newFilePath)
			throws IOException {
		File newImageFile=new File(newFilePath);
		if(!newImageFile.exists()){
			newImageFile.createNewFile();
		}
		FileInputStream in=new FileInputStream(
				oldFile);
		FileOutputStream out = new FileOutputStream(newFilePath);
		IOUtils.copy(in, out);
		in.close();
		out.flush();
		out.close();

	}

}