import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
/**
* ImageAction 2013-3-26 下午3:44:26
*
* @author 乔晓松
* 有疑问的请发送邮件到965266509@qq.com
*/
public class ImageCheck extends ActionSupport {
/**
*
*/
private static final long serialVersionUID = 1L;
private ByteArrayInputStream inputStream;
public void setInputStream(ByteArrayInputStream inputStream) {
this.inputStream = inputStream;
}
public ByteArrayInputStream getInputStream() {
return inputStream;
}
public String execute() throws Exception{
// 在内存中创建图象
int width=65, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 生成随机类
Random random = new Random();
// 设定背景色
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);
// 设定字体
g.setFont(new Font("Times New Roman",Font.PLAIN,18));
// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160,200));
for (int i=0;i<155;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x,y,x+xl,y+yl);
}
// 取随机产生的认证码(6位数字)
String sRand="";
for (int i=0;i<4;i++){
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
// 将认证码显示到图象中
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
g.drawString(rand,13*i+6,16);
}
// 将认证码存入SESSION
ActionContext.getContext().getSession().remove("randimg");
ActionContext.getContext().getSession().put("randimg",sRand);
// 图象生效
g.dispose();
ByteArrayOutputStream output = new ByteArrayOutputStream();
ImageOutputStream imageOut = ImageIO.createImageOutputStream(output);
ImageIO.write(image, "JPEG", imageOut);
imageOut.close();
ByteArrayInputStream input = new ByteArrayInputStream(output.toByteArray());
this.setInputStream(input);
return SUCCESS;
}
/*
* 给定范围获得随机颜色
*/
private Color getRandColor(int fc,int bc){
Random random = new Random();
if(fc>255) fc=255;
if(bc>255) bc=255;
int r=fc+random.nextInt(bc-fc);
int g=fc+random.nextInt(bc-fc);
int b=fc+random.nextInt(bc-fc);
return new Color(r,g,b);
}
}
Struts.xml代码：
[html]
< xml version="1.0" encoding="UTF-8" >
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">