java 验证码 生成器

java 验证码生成工具类

ValidateCode.java

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;


/**
 * 验证码工具类
 */
public class ValidateCode{
	
	private int width = 90;//验证码宽度 默认值：90
	private int height = 40;//验证码高度 默认值：40
	private int codeCount = 4;//验证码个数  默认值：4
	private int lineCount = 19;//混淆线个数  默认值：19 
	private int  fontSize = 20;//字体大小像素  
	//存储session中的key值 默认值："validateCode"
	private String sessionKey = "validateCode";
	
	public ValidateCode(){}
	
	/**
	 * 
	 * @param width 验证码宽度
	 * @param height 验证码高度
	 * @param fontSize 字体大小像素  
	 */
	public ValidateCode(int width,int height,int fontSize){
		this.width = width;
		this.height = height;
		this.fontSize = fontSize;
	}
	
	/**
	 * 
	 * @param width 验证码宽度
	 * @param height 验证码高度
	 * @param fontSize 字体大小像素  
	 * @param sessionKey 存储session中的key值
	 */
	public ValidateCode(int width,int height,int fontSize,String sessionKey){
		this.width = width;
		this.height = height;
		this.fontSize = fontSize;
		this.sessionKey = sessionKey;
	}
	
	/**
	 * 
	 * @param width 验证码宽度
	 * @param height 验证码高度
	 * @param codeCount 验证码个数
	 * @param fontSize 字体大小像素  
	 * @param sessionKey 存储session中的key值
	 */
	public ValidateCode(int width,int height,int codeCount,int fontSize,String sessionKey){
		this.width = width;
		this.height = height;
		this.codeCount = codeCount;
		this.fontSize = fontSize;
		this.sessionKey = sessionKey;
	}
	
	/**
	 * 
	 * @param width 验证码宽度
	 * @param height 验证码高度
	 * @param codeCount 验证码个数
	 * @param lineCount 混淆线个数
	 * @param fontSize 字体大小像素  
	 * @param sessionKey 存储session中的key值
	 */
	public ValidateCode(int width,int height,int codeCount,int lineCount,int fontSize,String sessionKey){
		this.width = width;
		this.height = height;
		this.codeCount = codeCount;
		this.lineCount = lineCount;
		this.fontSize = fontSize;
		this.sessionKey = sessionKey;
	}


    char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
            'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
            'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };

    /**
     * 具体获取验证码的方法
     * @param time  time为时戳,这样的话可以避免浏览器缓存验证码
     * @throws IOException
     */
    public void getCode(HttpServletRequest request,HttpServletResponse response){
        //定义随机数类
        Random r = new Random();
        //定义存储验证码的类
        StringBuilder builderCode = new StringBuilder();
        //定义画布
        BufferedImage buffImg = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
        //得到画笔
        Graphics g = buffImg.getGraphics();
        //1.设置颜色,画边框
        g.setColor(Color.gray);
        g.drawRect(0,0,width,height);
        //2.设置颜色,填充内部
        g.setColor(Color.white);
        g.fillRect(1,1,width-2,height-2);
        //3.设置干扰线
       // g.setColor(Color.gray);
        for (int i = 0; i < lineCount; i++) {
        	int _R = (int)Math.floor(Math.random()*256);
         	int _G = (int)Math.floor(Math.random()*256);
         	int _B = (int)Math.floor(Math.random()*256);
         	g.setColor(new Color(_R, _G, _B, 255));
            g.drawLine(r.nextInt(width),r.nextInt(width),r.nextInt(width),r.nextInt(width));
        }
        //4.设置验证码
        g.setColor(Color.blue);
        //4.1设置验证码字体
        g.setFont(new Font("宋体",Font.BOLD|Font.ITALIC,fontSize));
        for (int i = 0; i < codeCount; i++) {
            char c = codeSequence[r.nextInt(codeSequence.length)];
            builderCode.append(c);
            g.drawString(c+"",((width/codeCount)*i+2),height*4/5);
        }
		try {
			 //5.输出到屏幕
	        ServletOutputStream sos = response.getOutputStream();
			 ImageIO.write(buffImg,"png",sos);
		        //6.保存到session中
		        HttpSession session = request.getSession();
		        session.setAttribute(""+sessionKey+"",builderCode.toString());
		        //7.禁止图像缓存。
		        response.setHeader("Pragma", "no-cache");
		        response.setHeader("Cache-Control", "no-cache");
		        response.setDateHeader("Expires", 0);
		        response.setContentType("image/png");
		        //8.关闭sos
		        sos.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
       
    }
}

这里使用的是spring MVC 注解控制层

	/**
	 * 生成验证码
	 * @param time
	 * @param request
	 * @param response
	 * @return
	 */
	@RequestMapping(value="getCode")
	public void getCode(@RequestParam(value = "time") String time,HttpServletRequest request,HttpServletResponse response){
		ValidateCode code = new ValidateCode(100,30,4,30,25,"validateCode");
		code.getCode(request, response);
	}

页面jsp