java生成图片验证码

package com.pifeng.util;import java.awt.Color;import java.awt.Font;import java.awt.Graphics2D;import java.awt.RenderingHints;import java.awt.image.BufferedImage;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.util.Random;import javax.imageio.ImageIO;/** * @fun 产生图片验证码的工具类 * @date 2016/8/12 * @author 皮锋 * */public class CaptchaUtil {/** * 随机字典字符，不包括0、O、1、I这些难以辨认的字符 */private static final char[] CHARS = { '2', '3', '4', '5', '6', '7', '8','9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M','N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };/** * 随机数 */private static Random random = new Random();/** * @fun 获得length位随机数 * @date 2016/8/12 * @author 皮锋 * @param length */private static String getRandomString(int length) {StringBuffer buffer = new StringBuffer();// 字符串缓存for (int i = 0; i < length; i++) {// 循环length次// random.nextInt(n)方法调用返回介于0(含)和n(不含)伪随机，均匀分布的int值buffer.append(CHARS[random.nextInt(CHARS.length)]);// 每次获取一个随机字符}return buffer.toString();}/** * @fun 获得随机的颜色 * @date 2016/8/12 * @author 皮锋 */private static Color getRandomColor() {return new Color(random.nextInt(255), random.nextInt(255),random.nextInt(255));}/** * @fun 获得某的颜色反色 * @date 2016/8/12 * @author 皮锋 * @param c */private static Color getReverseColor(Color c) {return new Color(255 - c.getRed(), 255 - c.getGreen(),255 - c.getBlue());}/** * @fun 创建验证码图片 * @date 2016/8/12 * @author 皮锋 * @param width * @param height * @param os * @param randomString * @throws IOException */public static void outputImage(int width, int height, OutputStream os,String randomString) throws IOException {int verifySize = randomString.length(); // 验证码长度Color color = getRandomColor();// 随机颜色，用于背景色Color reverse = getReverseColor(color);// 反色，用于前景色BufferedImage bi = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);// 创建一个彩色图片Graphics2D g = bi.createGraphics();// 获取绘图对象g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON); // 设置图像抗锯齿g.setFont(new Font(Font.SANS_SERIF, Font.ITALIC, height - 4));// 设置字体: Serif的意思是，在字的笔划开始及结束的地方有额外的装饰，而且笔划的粗细会因直横的不同而有不同。相反的，Sans Serif则没有这些额外的装饰，笔划粗细大致差不多g.setColor(color);// 设置颜色g.fillRect(0, 0, width, height);// 绘制背景:用这个颜色填充这个区域g.setColor(reverse);// 设置颜色for (int i = 0; i < verifySize; i++) { // 绘制验证码g.drawChars(randomString.toCharArray(), i, 1,((width - 10) / verifySize) * i + 5, height / 2 + height/ 2 - 10);}drawNoisePoint(width, height, 500, g); // 绘制最多1000个噪音点drawInterferingLine(width, height, 30, g); // 产生30条干扰线shear(width, height, g, color);// 使图片扭曲g.dispose();// 释放由此 Window、其子组件及其拥有的所有子组件所使用的所有本机屏幕资源ImageIO.write(bi, "jpg", os);}/** * @fun 绘制最多num个噪音点 * @date 2016/8/12 * @author 皮锋 * @param width * @param height * @param num * @param g */private static void drawNoisePoint(int width, int height, int num,Graphics2D g) {for (int i = 0, n = random.nextInt(num); i < n; i++) {// 绘制最多num个噪音点g.drawRect(random.nextInt(width), random.nextInt(height), 1, 1);// 随机噪音点}}/** * @fun 产生n条干扰线 * @date 2016/8/12 * @author 皮锋 * @param width * @param height * @param n * @param g */private static void drawInterferingLine(int width, int height, int n,Graphics2D g) {for (int i = 0; i < n; i++) {int x = random.nextInt(width - 1);int y = random.nextInt(height - 1);int xl = random.nextInt(6) + 1;int yl = random.nextInt(12) + 1;g.drawLine(x, y, x + xl + 40, y + yl + 20);}}/** * @fun 使图片扭曲 * @date 2016/8/12 * @author 皮锋 * @param width * @param height * @param g * @param color */private static void shear(int width, int height, Graphics2D g, Color color) {shearX(g, width, height, color);shearY(g, width, height, color);}/** * @fun 使图片Y轴方向扭曲 * @date 2016/8/12 * @author 皮锋 * @param g * @param width * @param height * @param color */private static void shearY(Graphics2D g, int width, int height, Color color) {int period = random.nextInt(40) + 10; // 周期int frames = 20; // 帧int phase = 7; // 相位for (int i = 0; i < width; i++) {double d = (double) (period >> 1)* Math.sin((double) i / (double) period + (Math.PI * 2 * (double) phase) / (double) frames);g.copyArea(i, 0, 1, height, 0, (int) d);g.setColor(color);g.drawLine(i, (int) d, i, 0);g.drawLine(i, (int) d + height, i, height);}}/** * @fun 使图片X轴方向扭曲 * @date 2016/8/12 * @author 皮锋 * @param g * @param width * @param height * @param color */private static void shearX(Graphics2D g, int width, int height, Color color) {int period = random.nextInt(2);int frames = 1;int phase = random.nextInt(2);for (int i = 0; i < height; i++) {double d = (double) (period >> 1)* Math.sin((double) i / (double) period + (Math.PI * 2 * (double) phase) / (double) frames);g.copyArea(0, i, width, 1, (int) d, 0);g.setColor(color);g.drawLine((int) d, i, 0, i);g.drawLine((int) d + width, i, width, i);}}/** * @fun 生成指定验证码图像文件 * @date 2016/8/12 * @author 皮锋 * @param width * @param height * @param file * @param code * @throws IOException */public static void outputImageFile(int width, int height, File file,String code) throws IOException {if (file == null) {return;}File dir = file.getParentFile();// 获得父目录if (!dir.exists()) { // 如果父目录不存在，则创建一个dir.mkdirs();}try {file.createNewFile();FileOutputStream fos = new FileOutputStream(file);outputImage(width, height, fos, code); // 创建验证码图片fos.close(); // 关闭流} catch (IOException e) {throw e;}}public static void main(String[] args) throws IOException {File dir = new File("F:/verifies");int width = 200, height = 80;for (int i = 0; i < 50; i++) {String verifyCode = getRandomString(4);File file = new File(dir, verifyCode + ".jpg");outputImageFile(width, height, file, verifyCode);}}}

运行结果：