Java生成验证码
jopen
9年前
import java.awt.*; import java.awt.image.BufferedImage; import java.io.*; import java.util.Random; import javax.imageio.ImageIO; public class ValidationCode { // 图形验证码的字符集合，系统将随机从这个字符串中选择一些字符作为验证码 private static String codeChars = "%#23456789abcdefghkmnpqrstuvwxyzABCDEFGHKLMNPQRSTUVWXYZ"; // 返回一个随机颜色（Color对象） private static Color getRandomColor(int minColor, int maxColor) { Random random = new Random(); // 保存minColor最大不会超过255 if (minColor > 255) minColor = 255; // 保存minColor最大不会超过255 if (maxColor > 255) maxColor = 255; // 获得红色的随机颜色值 int red = minColor + random.nextInt(maxColor - minColor); // 获得绿色的随机颜色值 int green = minColor + random.nextInt(maxColor - minColor); // 获得蓝色的随机颜色值 int blue = minColor + random.nextInt(maxColor - minColor); return new Color(red, green, blue); } protected static void getValidationCode() throws IOException { try { // 获得验证码集合的长度 int charsLength = codeChars.length(); // 设置图形验证码的长和宽（图形的大小） int width = 90, height = 30; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics();// 获得用于输出文字的Graphics对象 Random random = new Random(); g.setColor(getRandomColor(180, 250));// 随机设置要填充的颜色 g.fillRect(0, 0, width, height);// 填充图形背景 // 设置初始字体 g.setFont(new Font("Times New Roman", Font.ITALIC, height)); g.setColor(getRandomColor(120, 180));// 随机设置字体颜色 // 用于保存最后随机生成的验证码 StringBuilder validationCode = new StringBuilder(); // 验证码的随机字体 String[] fontNames = { "Times New Roman", "Book antiqua", "Arial" }; // 随机生成3个到5个验证码 for (int i = 0; i < 3 + random.nextInt(3); i++) { // 随机设置当前验证码的字符的字体 g.setFont(new Font(fontNames[random.nextInt(3)], Font.ITALIC, height)); // 随机获得当前验证码的字符 char codeChar = codeChars.charAt(random.nextInt(charsLength)); validationCode.append(codeChar); // 随机设置当前验证码字符的颜色 g.setColor(getRandomColor(10, 100)); // 在图形上输出验证码字符，x和y都是随机生成的 g.drawString(String.valueOf(codeChar), 16 * i + random.nextInt(7), height - random.nextInt(6)); } File file = new File("d:\\code.png"); ImageIO.write(image, "png", file); System.out.println(validationCode.toString()); //byte[] data = ((DataBufferByte) image.getData().getDataBuffer()).getData(); g.dispose(); } catch (Exception e) { e.printStackTrace(); } } public static void main(String[] args) throws IOException{ getValidationCode(); } }