我看了網上大多數對圖片的壓縮都是基於對圖片width和hight進行裁剪來降低圖片實際大小，但這種方式容易導致圖片內容的丟失，所以推薦大家採用以下這種方式

import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.imageio.IIOImage
 
;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Picdownload {
    private final static Logger logger = LoggerFactory.getLogger(Picdownload.class);

    /**
     * 壓縮圖片
     * @param file
     * @param qality 引數qality是取值0~1範圍內  代表壓縮的程度
     * @return
     * @throws IOException
     */
 

    public static File compressPictureByQality(File file,float qality) throws IOException {
        BufferedImage src = null;
        FileOutputStream out = null;
        ImageWriter imgWrier;
        ImageWriteParam imgWriteParams;
        logger.info("開始設定壓縮圖片引數");
        // 指定寫圖片的方式為 jpg
        imgWrier = ImageIO.getImageWritersByFormatName
 
("jpg").next();
        imgWriteParams = new javax.imageio.plugins.jpeg.JPEGImageWriteParam(
                null);
        // 要使用壓縮，必須指定壓縮方式為MODE_EXPLICIT
        imgWriteParams.setCompressionMode(imgWriteParams.MODE_EXPLICIT);
        // 這裡指定壓縮的程度，引數qality是取值0~1範圍內，
        imgWriteParams.setCompressionQuality(qality);
        imgWriteParams.setProgressiveMode(imgWriteParams.MODE_DISABLED);
        ColorModel colorModel =ImageIO.read(file).getColorModel();// ColorModel.getRGBdefault();
        imgWriteParams.setDestinationType(new javax.imageio.ImageTypeSpecifier(
                colorModel, colorModel.createCompatibleSampleModel(32, 32)));
        logger.info("結束設定壓縮圖片引數");
        if (!file.exists()) {
             logger.info("Not Found Img File,檔案不存在");
            throw new FileNotFoundException("Not Found Img File,檔案不存在");
        } else {
            logger.info("圖片轉換前大小"+file.length()+"位元組");
            src = ImageIO.read(file);
            out = new FileOutputStream(file);
            imgWrier.reset();
            // 必須先指定 out值，才能呼叫write方法, ImageOutputStream可以通過任何
            // OutputStream構造
            imgWrier.setOutput(ImageIO.createImageOutputStream(out));
            // 呼叫write方法，就可以向輸入流寫圖片
            imgWrier.write(null, new IIOImage(src, null, null),
                    imgWriteParams);
            out.flush();
            out.close();
            logger.info("圖片轉換後大小"+file.length()+"位元組");
            return file;
        }
    }
}