图片验证码

package cn.itcast.image;

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 {
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="23456789abdcefghjkmnopqrstuvwxyzABCDEFGHJKMNPQRSTUVWXYZ";
private Color bgColor=new Color(255,255,255);
private String text;

private Color randomColor(){
int red=r.nextInt(150);
int green=r.nextInt(150);
int blue=r.nextInt(150);
return new Color(red,green,blue);
}

public char randomChar(){
return codes.charAt(r.nextInt(codes.length()));
}

private Font randomFont(){
int index=r.nextInt(fontNames.length);
String fontName=fontNames[index];
int style=r.nextInt(4);//随机生成的样式：0 无样式 1粗体  2斜体 3（粗体且斜体）
int size=r.nextInt(5)+24;//生成随机字号
return new Font(fontName,style,size);
}

private void drawLine(BufferedImage image){
int num=3;//一共画三条线
Graphics2D g2=(Graphics2D)image.getGraphics();
for(int i=0;i<num;i++){
int x1=r.nextInt(w);
int y1=r.nextInt(h);
int x2=r.nextInt(w);
int y2=r.nextInt(h);
g2.setStroke(new BasicStroke(1.5F));
g2.setColor(Color.BLUE);
g2.drawLine(x1, y1, x2, y2);
}
}

public BufferedImage getImage(){
BufferedImage image=createImage();
Graphics2D g2=(Graphics2D)image.getGraphics();
StringBuilder sb=new StringBuilder();
for(int i=0;i<4;i++){
String s=randomChar()+"";
sb.append(s);
float x=i*1.0F*w/4;
g2.setFont(randomFont());
g2.setColor(randomColor());
g2.drawString(s,x,h-5);
}
this.setText(sb.toString());
drawLine(image);
return image;
}

private void setText(String text) {
this.text=text;
}

public BufferedImage createImage(){
BufferedImage bi=new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2=(Graphics2D)bi.getGraphics();
g2.setColor(bgColor);
g2.fillRect(0, 0, w, h);
return bi;
}

public String getText() {
return text;
}
public static void output(BufferedImage image,OutputStream out){
try {
ImageIO.write(image, "JPEG", out);
} catch (IOException e) {
e.printStackTrace();
}
}
}