生成图片格式的验证码，图片格式验证码,package cn.o

生成图片格式的验证码，图片格式验证码,package cn.o

package cn.outofmemory.code;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.InputStream;import java.util.Random;import com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder;public class ImageCodeAction {    private InputStream input;    private static int WIDTH = 300;    private static int HEIGHT = 100;    private static int NUM = 4;    private static char[] seq = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I',            'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V',            'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8',            '9' };    public String execute() {        byte[] image = randomImage();        input = new ByteArrayInputStream(image);        return "success";    }    /**     *      * @return     */    private byte[] randomImage() {        Random r = new Random();        // 图片的内存映像        BufferedImage image = new BufferedImage(WIDTH, HEIGHT,                BufferedImage.TYPE_INT_RGB);        // 获得画笔对象        Graphics g = image.getGraphics();        g.setColor(randomColor(r));        g.fillRect(0, 0, WIDTH, HEIGHT);        g.setColor(new Color(0, 0, 0));        // 用于存储随机生成的验证码        StringBuffer number = new StringBuffer();        // 绘制验证码        for (int i = 0; i < NUM; i++) {            g.setColor(randomColor(r));            int h = (int) ((HEIGHT * 60 / 100) * r.nextDouble() + (HEIGHT * 30 / 100));            g.setFont(new Font(null, Font.BOLD | Font.ITALIC, h));            String ch = String.valueOf(seq[r.nextInt(seq.length)]);            number.append(ch);            g.drawString(ch, i * WIDTH / NUM * 90 / 100, h);        }        session.put("code", number.toString());        System.out.println(number.toString());        // 绘制干扰线        for (int i = 0; i <= 12; i++) {            g.setColor(randomColor(r));            g.drawLine(r.nextInt(WIDTH), r.nextInt(HEIGHT), r.nextInt(WIDTH), r                    .nextInt(HEIGHT));        }        ByteArrayOutputStream os = new ByteArrayOutputStream();        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(os);        // 把BufferedImage对象中的图像信息编码后        // 向创建该对象(encoder)时指定的输出流输出        try {            encoder.encode(image);            return os.toByteArray();        } catch (Exception e) {            throw new RuntimeException(e);        }    }    private Color randomColor(Random r) {        return new Color(r.nextInt(255), r.nextInt(255), r.nextInt(255));    }    public InputStream getInput() {        return input;    }    public void setInput(InputStream input) {        this.input = input;    }}