java 工具类 验证码

第一步： 引入工具类

 工具类一：

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Arrays;
import java.util.Random;

import javax.imageio.ImageIO;

public class ImageCodeUtil {

    public enum SecurityCodeLevel {
        Simple, Medium, Hard
    };

    public static String getSecurityCode() {
        return getSecurityCode(4, SecurityCodeLevel.Medium, false);
    }

    public static String getSecurityCode(int length, SecurityCodeLevel level, boolean isCanRepeat) {

        int len = length;

        char[] codes = { '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', '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' };

        if (level == SecurityCodeLevel.Simple) {
            codes = Arrays.copyOfRange(codes, 0, 10);
        } else if (level == SecurityCodeLevel.Medium) {
            codes = Arrays.copyOfRange(codes, 0, 36);
        }

        int n = codes.length;

        if (len > n && isCanRepeat == false) {
            throw new RuntimeException(String.format(
                    "调用SecurityCode.getSecurityCode(%1$s,%2$s,%3$s)出现异常�?" + "当isCanRepeat�?%3$s时，传入参数%1$s不能大于%4$s",
                    len, level, isCanRepeat, n));
        }

        char[] result = new char[len];

        if (isCanRepeat) {
            for (int i = 0; i < result.length; i++) {

                int r = (int) (Math.random() * n);

                result[i] = codes[r];
            }
        } else {
            for (int i = 0; i < result.length; i++) {

                int r = (int) (Math.random() * n);

                result[i] = codes[r];

                codes[r] = codes[n - 1];
                n--;
            }
        }
        return String.valueOf(result);
    }

    public static BufferedImage createImage(String securityCode) {

        int codeLength = securityCode.length();

        int fontSize = 18;

        int fontWidth = fontSize + 1;

        int width = codeLength * fontWidth + 6;
        int height = fontSize * 2 + 1;

        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

        Graphics2D g = image.createGraphics();

        g.setColor(Color.WHITE);

        g.fillRect(0, 0, width, height);

        g.setColor(Color.LIGHT_GRAY);

        g.setFont(new Font("Arial", Font.BOLD, height - 2));

        g.drawRect(0, 0, width - 1, height - 1);

        Random rand = new Random();

        g.setColor(Color.LIGHT_GRAY);

        for (int i = 0; i < codeLength * 6; i++) {

            int x = rand.nextInt(width);

            int y = rand.nextInt(height);

            g.drawRect(x, y, 1, 1);

        }

        int codeY = height - 10;

        g.setColor(new Color(19, 148, 246));

        g.setFont(new Font("宋体", Font.BOLD, fontSize));
        for (int i = 0; i < codeLength; i++) {
            double deg = new Random().nextDouble() * 20;
            g.rotate(Math.toRadians(deg), i * 16 + 13, codeY - 7.5);
            g.drawString(String.valueOf(securityCode.charAt(i)), i * 16 + 5, codeY);
            g.rotate(Math.toRadians(-deg), i * 16 + 13, codeY - 7.5);
        }

        g.dispose();

        return image;

    }

    public static void main(String[] args) throws IOException {

        String securityCode = getSecurityCode();

        System.out.println("====" + securityCode);

        BufferedImage image = createImage(securityCode);

        ImageIO.write(image, "png", new FileOutputStream(new File("D:\4.png")));
    }

}

工具类二：

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Arrays;
import java.util.Random;

import javax.imageio.ImageIO;

public class VerifyCodeUtil {
    public static final String VERIFY_CODES = "23456789ABCDEFGHJKMNPQRSTUVWXYZabcdefghjkmnpqrstuvwxyz";
    private static Random random = new Random();

    public static String generateVerifyCode(int verifySize) {
        return generateVerifyCode(verifySize, VERIFY_CODES);
    }

    public static String generateVerifyCode(int verifySize, String sources) {
        if (sources == null || sources.length() == 0) {
            sources = VERIFY_CODES;
        }
        int codesLen = sources.length();
        Random rand = new Random(System.currentTimeMillis());
        StringBuilder verifyCode = new StringBuilder(verifySize);
        for (int i = 0; i < verifySize; i++) {
            verifyCode.append(sources.charAt(rand.nextInt(codesLen - 1)));
        }
        return verifyCode.toString();
    }

    public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException {
        String verifyCode = generateVerifyCode(verifySize);
        outputImage(w, h, outputFile, verifyCode);
        return verifyCode;
    }

    public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException {
        String verifyCode = generateVerifyCode(verifySize);
        outputImage(w, h, os, verifyCode);
        return verifyCode;
    }

    public static void outputImage(int w, int h, File outputFile, String code) throws IOException {
        if (outputFile == null) {
            return;
        }
        File dir = outputFile.getParentFile();
        if (!dir.exists()) {
            dir.mkdirs();
        }
        try {
            outputFile.createNewFile();
            FileOutputStream fos = new FileOutputStream(outputFile);
            outputImage(w, h, fos, code);
            fos.close();
        } catch (IOException e) {
            throw e;
        }
    }

    public static BufferedImage getImage(int w, int h, String code) {
        int verifySize = code.length();
        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);
        g2.fillRect(0, 0, w, h);

        Color c = getRandColor(200, 250);
        g2.setColor(c);
        g2.fillRect(0, 2, w, h - 4);

        Random random = new Random();
        g2.setColor(getRandColor(160, 200));
        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);
        }

        float yawpRate = 0.05f;
        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);

        g2.setColor(getRandColor(100, 160));
        int fontSize = h - 4;
        Font font = new Font("Algerian", 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 / 4 * 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.dispose();
        return image;
    }

    public static void outputImage(int w, int h, OutputStream os, String code) throws IOException {
        BufferedImage image = getImage(w, h, code);
        ImageIO.write(image, "jpg", os);
    }

    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 getRandomIntColor() {
        int[] rgb = getRandomRgb();
        int color = 0;
        for (int c : rgb) {
            color = color << 8;
            color = color | c;
        }
        return color;
    }

    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 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 void main(String[] args) throws IOException {

        String generateVerifyCode = generateVerifyCode(4);

        System.out.println(generateVerifyCode);

        BufferedImage image = getImage(255, 80, generateVerifyCode);

        ImageIO.write(image, "png", new FileOutputStream(new File("D:\1.png")));
    }
}

第二步：前台页面 和 js 代码

<!-- 验证码 -->
                                    <input id="mycode1" type="text" name="code" />
                                </div>
                                <div class="Captcha-operate">
                                    <div class="Captcha-imageConatiner">
                                        <a class="code_pic" id="vcodeImgWrap" name="change_code_img"
                                            href="javascript:void(0);"> <img id="imgVcode" src="<c:url value='/code/captcher'/>"
                                            class="Ucc_captcha Captcha-image">
                                        </a>
                                         <a id="vcodeImgBtn" name="change_code_link"
                                                    class="code_picww" href="javascript:void(0)">换张图</a> 
                                                
                                                <span
                                                id="spn_vcode_ok" class="icon_yes pin_i"
                                                style="display: none;"></span> <span id="J_tipVcode"
                                                class="cue warn"></span>
                                    </div>

    js  代码

    //验证码
    $("#vcodeImgBtn").click(function() {
        $("#imgVcode").attr("src","/DangDang_zln/code/captcher?a="+new Date().getTime());
      });
    
     $("#vcodeImgWrap").click(function() {
         $("#imgVcode").attr("src","/DangDang_zln/code/captcher?a="+new Date().getTime());

  第三步：验证码action 类 页面访问的地址就是这个类

    public String Captcher() {

        String code = VerifyCodeUtil.generateVerifyCode(4);
        HttpSession session = ServletActionContext.getRequest().getSession();
        System.out.println(code);
        session.setAttribute("mycode", code);

        BufferedImage image = VerifyCodeUtil.getImage(255, 80, code);

        ServletActionContext.getRequest().getSession().setAttribute("code", code);

        HttpServletResponse response = ServletActionContext.getResponse();

        response.setContentType("image/png");
        try {
            ImageIO.write(image, "png", response.getOutputStream());
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return Action.NONE;

    }