网络地址图片压缩

将已经存入到FastFDS中的图片压缩：

首先从数据库中取出FastFDS返回的地址，然后将FastFDS返回的地址转换成推案文件

测试类

package com.msp.whg.service;

import com.msp.whg.domain.InfoManage;
import com.msp.whg.util.AppUUID;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import javax.imageio.ImageIO;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * Created by Administrator on 2018\2\1 0001.
 */
@SpringBootTest
@RunWith(SpringRunner.class)
public class test {

    @Autowired
    private InfoManageService infoManageService;

    public void transformer(File srcImageFile,int maxPixel) {

        String tarImage = "C:\\Users\\Administrator\\Desktop\\2015101713_720_720.jpg";

        //源图片文件
        //File srcImageFile = new File(srcImage);
        //目的图片文件
        File tarImageFile = new File(tarImage);
        // 生成图片转化对象
        AffineTransform transform = new AffineTransform();
        // 通过缓存读入缓存对象
        BufferedImage image = null;
        try {
            image = ImageIO.read(srcImageFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
        int imageWidth = image.getWidth();//原图片的高度
        int imageHeight = image.getHeight();//原图片的宽度
        int changeWidth = 0;//压缩后图片的高度
        int changeHeight = 0;//压缩后图片的宽度
        double scale = 0;// 定义小图片和原图片比例
        if (maxPixel != 0) {
            if (imageWidth > imageHeight) {
                changeWidth = maxPixel;
                scale = (double) changeWidth / (double) imageWidth;
                changeHeight = (int) (imageHeight * scale);
            } else {
                changeHeight = maxPixel;
                scale = (double) changeHeight / (double) imageHeight;
                changeWidth = (int) (imageWidth * scale);
            }
        }
        // 生成转换比例
        transform.setToScale(scale, scale);
        // 生成转换操作对象
        AffineTransformOp transOp = new AffineTransformOp(transform, null);
        //生成压缩图片缓冲对象
        BufferedImage basll = new BufferedImage(changeWidth, changeHeight, BufferedImage.TYPE_3BYTE_BGR);
        //生成缩小图片
        transOp.filter(image, basll);
        try {
            //输出缩小图片
            ImageIO.write(basll, "jpeg",tarImageFile);
        } catch (IOException e) {
            e.printStackTrace();
        }

        System.out.println(tarImage+"======================");

        InfoManage infoManage = new InfoManage();
        infoManage.setImLmmc("增加测试11111");
        infoManage.setImTitle("标题");
        infoManage.setBanner("1");
        infoManage.setImPath(tarImage);
        infoManageService.add(infoManage);
    }

    @Test
    public void InfoManageAdd(){
        String srcImage = "http://192.168.100.169/group1/M00/00/09/wKhkqVxAtBeAFg_yACBpQt4xiEo129.jpg";
        File file1 = null;
        byte[] btImg = getImageFromNetByUrl(srcImage);

        if(null != btImg && btImg.length > 0){
            System.out.println("读取到：" + btImg.length + " 字节");
            String fileName = "百度.gif";
            file1 = writeImageToDisk(btImg, fileName);
        }else{
            System.out.println("没有从该连接获得内容");
        }
        int maxPixel = 1220 ;
        transformer(file1,maxPixel);
    }

    /**
     * 将图片写入到磁盘
     * @param img 图片数据流
     * @param fileName 文件保存时的名称
     */
    public File writeImageToDisk(byte[] img, String fileName){
        File file = null;
        try {
            file = new File("C:\\Users\\Administrator\\Desktop\\" + fileName);
            FileOutputStream fops = new FileOutputStream(file);
            fops.write(img);
            fops.flush();
            fops.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return file;
    }

    /**
     * 根据地址获得数据的字节流
     * @param strUrl 网络连接地址
     * @return
     */
    public byte[] getImageFromNetByUrl(String strUrl){
        try {
            URL url = new URL(strUrl);
            HttpURLConnection conn = (HttpURLConnection)url.openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(5 * 1000);
            InputStream inStream = conn.getInputStream();//通过输入流获取图片数据
            byte[] btImg = readInputStream(inStream);//得到图片的二进制数据
            return btImg;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 从输入流中获取数据
     * @param inStream 输入流
     * @return
     * @throws Exception
     */
    public static byte[] readInputStream(InputStream inStream) throws Exception{
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while( (len=inStream.read(buffer)) != -1 ){
            outStream.write(buffer, 0, len);
        }
        inStream.close();
        return outStream.toByteArray();
    }


}