自动生成验证码图片的工具类,收藏起来备用.doc

原自动生成验证码图片的工具类，收藏起来备用。用法：直接调用其静态方法即可。Map map = ImageUtil.getImage();/获取图片，将图片转换成InputStream流String key = map.keySet().iterator().next();/获取图片上的字符BufferedImage image = map.get(key);/获取BufferedImage,赋值给imageStream其中，String为验证码的值，BufferedImage为验证码的图片。该工具类的代码如下：ImageUtil.javapackage action;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.util.HashMap;import java.util.Map;import java.util.Random;public final class ImageUtil private static final String chars = 0, 1, 2, 3, 4, 5, 6,7, 8, 9, A, B, C, D, E, F, G, H, I, 东,南, 西, 北, 中, 发, 白 ;private static final int SIZE = 5;/验证码长度private static final int LINES = 20;/干扰线条数private static final int WIDTH = 200;/图片宽度private static final int HEIGHT = 100;/图片高度private static final int FONT_SIZE = 60;/字体高度public static Map getImage() StringBuffer sb = new StringBuffer();BufferedImage image = new BufferedImage(WIDTH, HEIGHT,BufferedImage.TYPE_INT_RGB);Graphics graphic = image.getGraphics();graphic.setColor(Color.LIGHT_GRAY);graphic.fillRect(0, 0, WIDTH, HEIGHT);Random ran = new Random();/画随机字符for(int i=1;i=SIZE;i+)int r = ran.nextInt(chars.length);graphic.setColor(getRandomColor();graphic.setFont(new Font(null,Font.BOLD+Font.ITALIC,FONT_SIZE);graphic.drawString(charsr,(i-1)*WIDTH/SIZE , HEIGHT/2);sb.append(charsr);/将字符保存，存入Session/画干扰线for(int i=1;i=LINES;i+)graphic.setColor(getRandomColor();graphic.drawLine(ran.nextInt(WIDTH), ran.nextInt(HEIGHT), ran.nextInt(WIDTH),ran.nextInt(HEIGHT);Map map = new HashMap();map.put(sb.toString(), image);return map;public static Color getRandomColor()Random ran = new Random();Color color = new Color(ran.nextInt(256),ran.nextInt(256),ran.nextInt(256);return color;以下是在Struts2中调用该类并将图片转为InputStream的实例：package action;import java.awt.image.BufferedImage;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.util.Map;import com.opensymphony.xwork2.ActionContext;import com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder;public class ImageAction private InputStream imageStream;public String execute()/获取图片，将图片转换成InputStream流Map map = ImageUtil.getImage();String key = map.keySet().iterator().next();/获取图片上的字符/将字符写入sessionActionContext.getContext().getSession().put(code, key);/获取BufferedImage,赋值给imageStreamBufferedImage image = map.get(key);ByteArrayOutputStream bos = new ByteArrayOutputStream();JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(bos);try encoder.encode(image);imageStream = new ByteArrayInputStream(bos.toByteArray(); catch (IOException e) e.printStackTrace();return succes