改变图片的大小工具类

package net.longjin.comm.utils;



import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.Random;

/**
 * 描述:ChangeImgSize
 *
 * @author 何志鹏
 * @ClassName:ChangeImgSize
 * @create 2019-11-15 9:38
 * Version 1.0
 */
public class ChangeImgSize {
    public static boolean changeSize(int newWidth, int newHeight, String path) {
        BufferedInputStream in = null;
        try {
            in = new BufferedInputStream(new FileInputStream(path));

            //字节流转图片对象
            Image bi = ImageIO.read(in);
            //构建图片流
            BufferedImage tag = new BufferedImage(newWidth, newHeight, BufferedImage.TYPE_INT_RGB);
            //绘制改变尺寸后的图
            tag.getGraphics().drawImage(bi, 0, 0, newWidth, newHeight, null);
            //输出流
            BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(path));
            //JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
            //encoder.encode(tag);
            ImageIO.write(tag, "PNG", out);
            in.close();
            out.close();
            return true;
        } catch (IOException e) {
            return false;
        }
    }






       public static void main(String[] args) {
           //生成四位随机数
           Random ne=new Random();
           int num=ne.nextInt(9999-1000+1)+1000;
           String random = String.valueOf(num);
           String fileName = "" + System.currentTimeMillis()+random;
           String  newPdfPath = "D:/photo/"+fileName;
          // changeSize("D:/photo/cc.png", newPdfPath,  1920);
           changeSize( 1920,  1080,  "D:/photo/cc.jpg");
    }
}