package utils;

 

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics2D;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.IOException;

import java.util.Random;

import javax.imageio.ImageIO;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class CodeUtils {

 //10.得到随机数

 private static char[] chars = "abdefghijkmnpqrstuvwxyABCDEFGHIJKLMNPQRSTUVWXY3456789".toCharArray();

 private static Random random = new Random();

 private static String getCode(int length){

  StringBuffer sb = new StringBuffer();

  for(int i=0;i<length;i++){

   sb.append(chars[random.nextInt(chars.length)]);

  }

  return sb.toString();

 }

 

 public static void createCode(HttpServletRequest req,HttpServletResponse resp){

  try {

   //1.创建画布

   BufferedImage bufferedImage = new BufferedImage(120, 34, BufferedImage.TYPE_INT_RGB);

   //2.创建画笔

   Graphics2D graphics2d = bufferedImage.createGraphics();

   //6.设置背景颜色  ， 先设置画笔颜色  ，在把画布涂满

   graphics2d.setColor(new Color(249, 250, 108));

   //7.涂满画布

   graphics2d.fillRect(0, 0, 120, 34);

   //8.更新画笔颜色

   graphics2d.setColor(new Color(62, 128, 27));

   //9.设置字体

   graphics2d.setFont(new Font("Dope Crisis", Font.PLAIN, 40));

   String code = getCode(4);

   //12.保存到sesssion中

   HttpSession session=req.getSession();

   session.setAttribute("code", code);

   session.setMaxInactiveInterval(1000);

   //3.写字

   graphics2d.drawString(code, 25,30);

   //4.收笔

   graphics2d.dispose();

   //5.保存到服务器上

   ImageIO.write(bufferedImage, "jpg", resp.getOutputStream());

  } catch (IOException e) {

   e.printStackTrace();

  }

 }

 

 

 

 

 

 

 

 

 

 

 

 

 

 public static void main(String[] args) throws Exception {

  //1.创建画布

  BufferedImage bufferedImage = new BufferedImage(120, 34, BufferedImage.TYPE_INT_RGB);

  //2.创建画笔

  Graphics2D graphics2d = bufferedImage.createGraphics();

  //6.设置背景颜色  ， 先设置画笔颜色  ，在把画布涂满

  graphics2d.setColor(new Color(20, 123, 228));

  //7.涂满画布

  graphics2d.fillRect(0, 0, 120, 34);

  //8.更新画笔颜色

  graphics2d.setColor(new Color(246, 129, 50));

  //9.设置字体

  graphics2d.setFont(new Font("Dope Crisis", Font.PLAIN, 40));

  String num = getCode(4);

  //3.写字

  graphics2d.drawString(num, 25,30);

  //4.收笔

  graphics2d.dispose();

  //5.保存到硬盘上

  ImageIO.write(bufferedImage, "jpg", new File("c:\\abc.jpg"));

 }

 //11.保存到服务器上

}