使用java生成字母验证码

 import java.awt.BasicStroke; import java.awt.Color; import java.awt.Font; import java.awt.Graphics2D; import java.awt.image.BufferedImage; import java.io.IOException; import java.io.OutputStream; import java.util.Random; import javax.imageio.ImageIO; public class VerifyCode <em style="color:transparent">来源gao.dai.ma.com搞@代*码网</em>{ //图片宽高 private int w=70; private int h=35; private Random r=new Random(); private String[] fontNames={"宋体","华文楷体","黑体","微软雅黑","楷体_GB2312"}; private String codes="234567890qwertyuipasdfghjkzxcvbnmQWERTYUIPASDFGHJKZXCVBNM"; private Color bgColor=new Color(255,255,255); private String text; //生成随机颜色 private Color randomColor(){ int red=r.nextInt(150); int green=r.nextInt(150); int blue=r.nextInt(150); return new Color(red, green, blue); } //生成随机字体 private Font randomFont(){ int index=r.nextInt(fontNames.length); String fontName=fontNames[index]; int style=r.nextInt(4);//0 无 1 粗体 2 斜体 3 粗+斜 int size=r.nextInt(5)+24; //生成随机字号 24~28 return new Font(fontName, style, size); } //干扰线 private void drowLine(BufferedImage image){ //生成4条干扰线 int num=4; Graphics2D bi=(Graphics2D) image.getGraphics(); for (int i = 0; i <num; i++) { int x1=r.nextInt(w); int x2=r.nextInt(w); int y1=r.nextInt(h); int y2=r.nextInt(h); bi.setStroke(new BasicStroke(1.5F)); bi.setColor(Color.BLUE);//干扰线色 bi.drawLine(x1,y1,x2,y2); } } //随机生成一个字符 private char randomChar(){ int index=r.nextInt(codes.length()); return codes.charAt(index); } //图片缓冲区 private BufferedImage createImage(){ BufferedImage image=new BufferedImage(w, h, BufferedImage.TYPE_INT_BGR); Graphics2D bi=(Graphics2D) image.getGraphics(); bi.setColor(this.bgColor); bi.fillRect(0, 0, w, h); return image; } //生成图片 public BufferedImage getImage(){ BufferedImage image=createImage(); Graphics2D bi=(Graphics2D) image.getGraphics(); StringBuilder sb=new StringBuilder(); for (int i = 0; i <4; i++) { String string=randomChar()+""; sb.append(string); //每个字符占图片1/4宽 float x=i*1.0F*w/4; //随机字体格式 bi.setFont(randomFont()); bi.setColor(randomColor()); //把字写在图片适当处（h-6指图片距底部6个高度） bi.drawString(string, x, h-6); } this.text=sb.toString(); drowLine(image); return image; } //返回得到的字体 public String getText(){ return text; } //把图片写入指定位置 public static void output(BufferedImage image,OutputStream out){ try { ImageIO.write(image, "JPG", out); } catch (IOException e) { e.printStackTrace(); } } }