java图片压缩代码

java压缩图片类
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class PicCompression {
    private int wideth;
    private int height;
    private String t = null;

    public void setT(String t) {
        this.t = t;
    }

    public void setWideth(int wideth) {
        // wideth=320;
        this.wideth = wideth;
    }

    public int getWideth() {
        return this.wideth;
    }

    public void setHeight(int height) {
        // height=240;
        this.height = height;
    }

    public int getHeight(int w, int h) // former images size
    {
        // int hhh;
        if (w > wideth) {
            float ww;
            ww = (float) w / (float) wideth;
            float hh = h / ww;
            return (int) hh;
        } else {
            this.setWideth(w);
            return h;
        }

    }

    public void proce(String fpath) throws Exception {
        File _file = new File(fpath);
        Image src = javax.imageio.ImageIO.read(_file);
        int wideth = src.getWidth(null);
        int height = src.getHeight(null);
        int h = this.getHeight(wideth, height);
        BufferedImage tag = new BufferedImage(this.getWideth(), h,
                BufferedImage.TYPE_INT_RGB);
        Graphics g = tag.getGraphics();
        g.drawImage(src, 0, 0, this.getWideth(), h, null);
        if (t != null) {
            g.setColor(new Color(242, 242, 242));
            g.fillRect(this.getWideth() - 120, h - 18, 120, 18);
            g.setColor(new Color(180, 180, 180));
            g.drawRect(this.getWideth() - 120, h - 18, 119, 17);
            g.setColor(new Color(255, 102, 0));
            g.drawString(t, this.getWideth() - 100, h - 5);
        }
        FileOutputStream out = new FileOutputStream(fpath);
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        encoder.encode(tag);
        out.close();
    }

    /**
    * 压缩图片方法
    * 
    * @param oldFile
    *            将要压缩的图片
    * @param width
    *            压缩宽
    * @param height
    *            压缩长
    * @param quality
    *            压缩清晰度 <b>建议为1.0</b>
    * @param smallIcon
    *            压缩图片后,添加的扩展名
    * @return
    */
    public String proce1(String oldFile, int width, int height, float quality,
            String smallIcon) {
        if (oldFile == null) {
            return null;
        }
        String newImage = null;
        try {
            File file = new File(oldFile);
            if(!file.exists()) //文件不存在时
                return null;
            /** 对服务器上的临时文件进行处理 */
            Image srcFile = ImageIO.read(file);
            // 为等比缩放计算输出的图片宽度及高度
            double rate1 = ((double) srcFile.getWidth(null)) / (double) width
                    + 0.1;
            double rate2 = ((double) srcFile.getHeight(null)) / (double) height
                    + 0.1;
            double rate = rate1 > rate2 ? rate1 : rate2;
            int new_w = (int) (((double) srcFile.getWidth(null)) / rate);
            int new_h = (int) (((double) srcFile.getHeight(null)) / rate);
            /** 宽,高设定 */
            BufferedImage tag = new BufferedImage(new_w, new_h,
                    BufferedImage.TYPE_INT_RGB);
            tag.getGraphics().drawImage(srcFile, 0, 0, new_w, new_h, null);
            String filePrex = oldFile.substring(0, oldFile.indexOf('.'));
            /** 压缩后的文件名 */
            // newImage =smallIcon + filePrex
            // +oldFile.substring(filePrex.length());
            newImage = filePrex + smallIcon
                    + oldFile.substring(filePrex.length());
            // newImage = smallIcon;
            /** 压缩之后临时存放位置 */
            FileOutputStream out = new FileOutputStream(newImage);

            JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
            JPEGEncodeParam jep = JPEGCodec.getDefaultJPEGEncodeParam(tag);
            /** 压缩质量 */
            jep.setQuality(quality, true);
            encoder.encode(tag, jep);

            out.close();
            srcFile.flush();

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return newImage;
    }

    //
    public static void main(String str[]) {
        PicCompression ps = new PicCompression();
        try {
            System.out.println(ps.proce1("D:/5.jpg",
                    640, 480, 1, "1"));
            System.out.println(ps.proce1("D:/5.jpg",
                    240, 240, 1, "2"));
            System.out.print("图片压缩成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}