verifycode.java

web端随机验证码图片生成

package com.mno5.bbs.util.system.verify;
/**********************************************************************
 *    myniko tools Release 1.0
 *    ?Copyright myniko.com 2003
 ************************************************************************/
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;

/**
 * <p>
 * Title: <font color=red>VerifyCode</font>
 * Description:
 * Copyright: Copyright (c) 2002
 * Company: www.myniko.com
 * @author <font color=red>niko </font>
 * @version 1.0
 */

public class VerifyCode
{

    public static final int NUMBER_ONLY = 0;
    public static final int LETTER_ONLY = 1;
    public static final int NUMBER_AND_LETTER = 2;
    public static final int MICROSOFT_SERIAL_NUMBER = 3;
    private static final char NUMBER[] = {
        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'
    };
    private static final char LETTER[] = {
        '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'
    };
    private static final char NUMBER_LETTER[] = {
        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
        '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'
    };
    private static final char MICROSOFT_SN[] = {
        '2', '3', '4', '6', '7', '8', '9', 'B', 'C', 'D',
        'F', 'G', 'H', 'J', 'K', 'M', 'P', 'Q', 'R', 'T',
        'V', 'W', 'X', 'Y'
    };
    private static final char CODE_ELEMENTS[][] = {
        NUMBER, LETTER, NUMBER_LETTER, MICROSOFT_SN
    };
    private String code;
    private Color fColor;
    private Color bColor;
    private int style;
    private int length;

    public VerifyCode()
    {
        code = "";
        fColor = Color.RED;
        bColor = Color.WHITE;
        style = 3;
        length = 4;
    }

    public BufferedImage getImage()
    {
        int top = 1;
        int left = 4;
        BufferedImage image = new BufferedImage(1, 1, 1);
        reset();
        StringBuffer sb = new StringBuffer(code.length() * 2);
        for(int i = 0; i < code.length(); i++)
        {
            sb.append(code.charAt(i));
            sb.append(' ');
        }

        String show = sb.substring(0, sb.length() - 1);
        int showHeight = image.getGraphics().getFontMetrics().getHeight();
        int showWidth = image.getGraphics().getFontMetrics().stringWidth(show);
        int imageHeight = showHeight + 2 * top;
        int imageWidth = showWidth + 2 * left;
        image = new BufferedImage(imageWidth, imageHeight, 1);
        Graphics2D g = image.createGraphics();
        g.setColor(bColor);
        g.fillRect(0, 0, imageWidth, imageHeight);
        g.setColor(fColor);
        g.drawString(show, left, (g.getFontMetrics().getHeight() - g.getFontMetrics().getDescent() - g.getFontMetrics().getLeading()) + top);
        g.drawRect(0, 0, imageWidth - 1, imageHeight - 1);
        g.setColor(bColor);
        g.drawLine(1, imageHeight / 2, imageWidth - 2, imageHeight / 2);
        return image;
    }

    public boolean isVerify(String string)
    {
        return string.toUpperCase().matches(code);
    }

    public void setBColor(Color color)
    {
        bColor = color;
    }

    public void setBColor(String color)
    {
        bColor = decodeColor(color);
    }

    public void setCode(String string)
    {
        code = string;
    }

    public void setFColor(Color color)
    {
        fColor = color;
    }

    public void setFColor(String color)
    {
        fColor = decodeColor(color);
    }

    public void setLength(int i)
    {
        length = i;
    }

    public void setStyle(int i)
    {
        style = i;
    }

    private void reset()
    {
        reset(length);
    }

    private void reset(int len)
    {
        StringBuffer sb = new StringBuffer(len);
        Random random = new Random(System.currentTimeMillis());
        for(int i = 0; i++ < len;)
            sb.append(CODE_ELEMENTS[style][random.nextInt(CODE_ELEMENTS[style].length)]);
        code = sb.toString();
    }

    private static Color decodeColor(String color)
    {
        Color c = null;
        if(!color.startsWith("0x"))
        {
            if(color.indexOf("|") != -1)
            {
                String temp[] = color.split("\\|");
                int colorSet[] = new int[3];
                int i;
                for(i = 0; i < temp.length; i++)
                    colorSet[i] = Integer.valueOf(temp[i]).intValue();

                if(i < 3)
                    for(; i < 3; i++)
                        colorSet[i] = 0;

                c = new Color(colorSet[0], colorSet[1], colorSet[2]);
            } else
            {
                c = Color.decode("0x" + color);
            }
        } else
        {
            c = Color.decode(color);
        }
        return c;
    }

}