<%@page import="javax.imageio.ImageIO"%>
<%@page import="java.awt.Color"%>
<%@page import="java.awt.Graphics"%>
<%@page import="java.awt.image.BufferedImage"%>
<%@ page language="java" import="java.util.*" contentType="image/JPEG" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
生成验证码
<%!
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);
}
private String getRandomChar(){
int rand = (int) Math.round(Math.random()*2);
long itmp = 0;
char ctmp = '\u0000';
switch(rand){
case 1:
itmp = Math.round(Math.random()*25+65);
ctmp = (char)itmp;
return String.valueOf(ctmp);
case 2:
itmp = Math.round(Math.random()*25+65);
ctmp = (char)itmp;
return String.valueOf(ctmp);
default:
itmp = Math.round(Math.random()*9);
return String.valueOf(itmp);
}
}
%>
<%
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
int width=70,height=20;
BufferedImage image=new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200, 250));
g.fillRect(1, 1, width - 1, height - 1);
g.setColor(new Color(102, 102, 102));
g.drawRect(0, 0, width - 1, height - 1);
g.setColor(getRandColor(160, 200));
/*
for(int i=0;i<160;i++){
int x = random.nextInt(width-1);
int y = random.nextInt(height-1);
int x1 = random.nextInt(6) + 1;
int y1 = random.nextInt(12) + 1;
g.drawLine(x, y, x+x1, y+y1);
}
for(int i=0;i<70;i++){
int x = random.nextInt(width-1);
int y = random.nextInt(height-1);
int x1 = random.nextInt(6) + 1;
int y1 = random.nextInt(12) + 1;
g.drawLine(x, y, x+x1, y+y1);
}*/
String sRand="";
for(int i=0;i<4;i++){
String tmp=getRandomChar();
sRand += tmp;
g.setColor(Color.red);
g.drawString(tmp, 15*i+10, 15);
}
session.setAttribute("rand", sRand);
g.dispose();
ImageIO.write(image, "JPEG", response.getOutputStream());
response.getOutputStream().flush();
response.getOutputStream().close();
response.flushBuffer();
out.clear();
out = pageContext.pushBody();
%>