CaptchaUtilsEx.java

package com.starcharge.base.util;

import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.util.Arrays;
import java.util.Random;

/**
 * 图片验证码工具类
 */
public class CaptchaUtilsEx {
    
    // 使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，去掉了1,0,i,o几个容易混淆的字符
    public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";

    public static final String VERIFY_CODES_NUMBER = "0123456789";
    
    private static Random random = new Random();
    
    private BufferedImage image;

	private String imageCode;
	
	public BufferedImage getImage() {
		return image;
	}

	public String getImageCode() {
		return imageCode;
	}
	
	public CaptchaUtilsEx(Integer width, Integer height, Integer verifySize) {
		this.imageCode = generateVerifyCode(verifySize, false);
		this.image = getImage(width, height, verifySize, this.imageCode);
	}

    public CaptchaUtilsEx(Integer width, Integer height, Integer verifySize, boolean onlyNumber) {
        this.imageCode = generateVerifyCode(verifySize, onlyNumber);
        this.image = getImage(width, height, verifySize, this.imageCode);
    }
    
    public static String generateVerifyCode(int verifySize, boolean onlyNumber) {
	    String verifyCodeLib = onlyNumber ? VERIFY_CODES_NUMBER : VERIFY_CODES;
        int codesLen = verifyCodeLib.length();
        Random rand = new Random(System.currentTimeMillis());
        StringBuilder verifyCode = new StringBuilder(verifySize);
        for (int i = 0; i < verifySize; i++) {
            verifyCode.append(verifyCodeLib.charAt(rand.nextInt(codesLen - 1)));
        }
        return verifyCode.toString();
    }
    
    private static Color getRandColor(int fc, int bc) {
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }
    
    private static int[] getRandomRgb() {
        int[] rgb = new int[3];
        for (int i = 0; i < 3; i++) {
            rgb[i] = random.nextInt(255);
        }
        return rgb;
    }
    
    private static int getRandomIntColor() {
        int[] rgb = getRandomRgb();
        int color = 0;
        for (int c : rgb) {
            color = color << 8;
            color = color | c;
        }
        return color;
    }
    
    private static void shear(Graphics g, int w1, int h1, Color color) {
        shearX(g, w1, h1, color);
        shearY(g, w1, h1, color);
    }
    
    private static void shearX(Graphics g, int w1, int h1, Color color) {
        
        int period = random.nextInt(2);
        
        boolean borderGap = true;
        int frames = 1;
        int phase = random.nextInt(2);
        
        for (int i = 0; i < h1; i++) {
            double d =
                (double)(period >> 1) * Math.sin((double)i / (double)period + (6.2831853071795862D * (double)phase) / (double)frames);
            g.copyArea(0, i, w1, 1, (int)d, 0);
            if (borderGap) {
                g.setColor(color);
                g.drawLine((int)d, i, 0, i);
                g.drawLine((int)d + w1, i, w1, i);
            }
        }
        
    }
    
    private static void shearY(Graphics g, int w1, int h1, Color color) {
        
        int period = random.nextInt(40) + 10; // 50;
        
        boolean borderGap = true;
        int frames = 20;
        int phase = 7;
        for (int i = 0; i < w1; i++) {
            double d =
                (double)(period >> 1) * Math.sin((double)i / (double)period + (6.2831853071795862D * (double)phase) / (double)frames);
            g.copyArea(i, 0, 1, h1, 0, (int)d);
            if (borderGap) {
                g.setColor(color);
                g.drawLine(i, (int)d, i, 0);
                g.drawLine(i, (int)d + h1, i, h1);
            }
            
        }
        
    }
    
    public static BufferedImage getImage(int w, int h, Integer verifySize, String code) {
        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
        Random rand = new Random();
        Graphics2D g2 = image.createGraphics();
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        Color[] colors = new Color[5];
        Color[] colorSpaces =
            new Color[]{Color.WHITE, Color.CYAN, Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE, Color.PINK, Color.YELLOW};
        float[] fractions = new float[colors.length];
        for (int i = 0; i < colors.length; i++) {
            colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
            fractions[i] = rand.nextFloat();
        }
        Arrays.sort(fractions);
        
        g2.setColor(Color.GRAY);// 设置边框色
        g2.fillRect(0, 0, w, h);
        
        Color c = getRandColor(200, 250);
        g2.setColor(c);// 设置背景色
        g2.fillRect(0, 2, w, h - 4);
        
        // 绘制干扰线
        Random random = new Random();
        g2.setColor(getRandColor(160, 200));// 设置线条的颜色
        for (int i = 0; i < 20; i++) {
            int x = random.nextInt(w - 1);
            int y = random.nextInt(h - 1);
            int xl = random.nextInt(6) + 1;
            int yl = random.nextInt(12) + 1;
            g2.drawLine(x, y, x + xl + 40, y + yl + 20);
        }
        
        // 添加噪点
        float yawpRate = 0.05f;// 噪声率
        int area = (int)(yawpRate * w * h);
        for (int i = 0; i < area; i++) {
            int x = random.nextInt(w);
            int y = random.nextInt(h);
            int rgb = getRandomIntColor();
            image.setRGB(x, y, rgb);
        }
        
        shear(g2, w, h, c);// 使图片扭曲
        
        g2.setColor(getRandColor(100, 160));
        int fontSize = h - 4;
        //设置验证码字体， 如"Algerian"
        Font font = new Font(null, Font.ITALIC, fontSize);
        g2.setFont(font);
        char[] chars = code.toCharArray();
        for (int i = 0; i < verifySize; i++) {
            AffineTransform affine = new AffineTransform();
            affine.setToRotation(Math.PI / 6 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize / 2,
                h / 2);
            g2.setTransform(affine);
//            g2.drawChars(chars, i, 1, ((w - 10) / verifySize) * i + 5, h / 2 + fontSize / 2 - 10);
            g2.drawChars(chars, i, 1, (w / verifySize) * i , h / 2 + fontSize / 2 - 5);
        }
        
        g2.dispose();
        return image;
    }
}