java实现一个简单的验证码生成器

　　最近看了网上很多大佬们写的验证码生成，寻思着自己也写一个，话不多说，代码如下：

 import java.awt.BasicStroke;
 import java.awt.Color;
 import java.awt.Font;
 import java.awt.Graphics2D;
 import java.awt.image.BufferedImage;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.Random;

 import javax.imageio.ImageIO;

 public class VerifyCode {
     private int width = 90;
     private int high = 40;
     private Random random = new Random();
     private String[] fonts = {"宋体", "微软雅黑", "TimesRoman", "Cambria"};
     private String chars = "1234567890";
     private String operator = "+-x";
     private Color backColor = Color.white;
     private String text;
     private int no1;
     private int no2;
     private String op;

     //获取随机颜色
     private Color randomColor()
     {
         int red = random.nextInt(150);
         int green = random.nextInt(150);
         int blue =random.nextInt(150);
         return new Color(red,green,blue);
     }

     //method：获取随机字体
     private Font randomFont()
     {
         int index = random.nextInt(fonts.length);
         String fontName = fonts[index];
         int style = random.nextInt(4);
         int size = 24+random.nextInt(4);

         return new Font(fontName,style,size);
     }
     //method：获取随机操作符号
     private String randomOperator()
     {
         int index = random.nextInt(3);
         return operator.charAt(2)+"";
     }

     //method：获取随机数字
     private String randomNum()
     {
         int index = random.nextInt(chars.length());
         return chars.charAt(index)+"";
     }

     //method：添加干扰线
     private void drawLine(BufferedImage image)
     {
         int num = 3;
         Graphics2D graphic = (Graphics2D)image.getGraphics();
         for(int i=0;i<num;i++)
         {
             int x1 = random.nextInt(width);
             int x2 = random.nextInt(width);
             int y1 = random.nextInt(high);
             int y2 = random.nextInt(high);
             graphic.setColor(this.randomColor());
             graphic.setStroke(new BasicStroke(1.5F));
             graphic.drawLine(x1,y1,x2,y2);
         }
     }
     //method：绘制方法
     private void drawString(Graphics2D graphics,String s,float position)
     {
         graphics.setColor(randomColor());
         graphics.setFont(randomFont());
         graphics.drawString(s,position,high -5);
     }

     //获取图片缓存
     public BufferedImage getImage()
     {
         BufferedImage bi = new BufferedImage(width,high,BufferedImage.TYPE_INT_RGB);
         Graphics2D g2 = (Graphics2D)bi.getGraphics();
         g2.setColor(this.backColor);
         g2.fillRect(0, 0, 90, 40);
         StringBuilder sb = new StringBuilder();

             //获取操作数s1，绘制
             String s1 = randomNum();
             this.no1 = Integer.parseInt(s1);
             float p1 = 5.0F;
             sb.append(s1);
             drawString(g2,s1,p1);

             //获取操作符oper，绘制
             String oper = randomOperator().trim();
             this.op = oper;
             sb.append(oper);
             float p2 = 1.0F*width/5;
             drawString(g2,oper,p2);

             //获取操作数s2，绘制
             String s2 = randomNum();
             this.no2 = Integer.parseInt(s2);
             float p3 = 2.0F*width/5;
             sb.append(s2);
             drawString(g2,s2,p3);

             //绘制 等号和问号
             String calculate = "=?";
             float p4 = 3.0F*width/5;
             drawString(g2,calculate,p4);

             //绘制干扰线
             drawLine(bi);

             //返回BufferedImage图片
             return bi;
     }

     //获取算术的运算结果
     public int getValue()
     {
         int value = 0;
         switch(this.op)
         {
             case "+": value = this.no1+this.no2;break;
             case "-": value = this.no1-this.no2;break;
             case "x":value = this.no1*this.no2;break;
             default :value = 0;
         }
         return value;
     }

     //将图片缓存bi输出到指定的输出流out
     public static void output(BufferedImage bi, OutputStream out)
             throws FileNotFoundException, IOException
     {
         ImageIO.write(bi,"JPEG",out);
     }
 }

测试代码如下：

    @Test
    public void test1()
    {
        VerifyCode verifyCode = new VerifyCode();
        BufferedImage bi = verifyCode.getImage();

        FileOutputStream out;
        try
        {
            out = new FileOutputStream("H:\\verifyCode.jpg");
            VerifyCode.output(bi, out);
        }catch (Exception e)
        {
            e.printStackTrace();
        }
        System.out.println(verifyCode.getValue());
    }

生成的验证码图片如下：

　　

程序输出结果如下：

18

以上，只实现了10以内的加减乘，除法都没有，毕竟作为验证码，除法还要考虑除数非0、整除等内容，因此未添加除法。各位看看就好，水平有限，请多多指教！