[Tools] image verification code

java background authentication code generation, returns a base64 string

// ==== two-dimensional code generation tool method ====================================== = //
     / **
     * Instructions
     * import java.awt.Graphics2D;
       import java.awt.image.BufferedImage;
       
       BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
        Graphics2D g = (Graphics2D) image.getGraphics();
        // 1, set the background color
        Utils.setBackGround(g,width,height);
        // 2, set the border
        Utils.setBorder(g,width,height);
        // 3, draw the line of interference
        Utils.drawRandomLine(g,width,height);
        // 4, write random numbers
        String verifycode = Utils.drawRandomNum(g);
        // 5, addressed to the browser
        g.dispose ();
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ImageIO.write(image, "JPEG", bos);
        byte[] buf = bos.toByteArray();
        String img = Base64Util.encode(buf);// "/9j/4AAQSkZJRgABAgA" --图片base64
        bos.close();
        return img;
     */
    /**
     * Description generate graphics codes
     * @Param width image width default 96
     * @Param height Image Height default 42
     * @Return picture base64, img file the string "/ 9j / 4AAQSkZJRgABAgA" removed "data: image / jpeg; base64 ," part
     * @author 
     * @Date 2019 Nian 9 Yue 20 Ri
     */
    public static String imgVerifycode(int width,int height) throws Exception{
        if(width < 96){
            width = 96;
        }
        if(height < 42){
            height = 42;
        }
        BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
        G the Graphics2D = (the Graphics2D) image.getGraphics ();
         // . 1, background color 
        setBackground (G, width, height);
         // 2, set the border 
        the setBorder (G, width, height);
         // . 3, line drawing interference 
        drawRandomLine (G, width, height);
         // . 4, the random number nonce write returns 
        String verifycode = drawRandomNum (G);
         // . 5, the browser written 
        g.dispose ();
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ImageIO.write(image, "JPEG", bos);
        byte[] buf = bos.toByteArray();
        String img = Base64Util.encode(buf);// "/9j/4AAQSkZJRgABAgA" --图片base64
        bos.close();
        return img;
    }
    // set the background color 
    public  static  void setBackground (G Graphics, width Integer, Integer height) {
        g.setColor(Color.WHITE);
        g.fillRect(0, 0, width, height);
        for (int i = 0; i < 120; i++) {
            int x = (int) (Math.random() * width);
            int y = (int) (Math.random() * height);
            int red = (int) (Math.random() * 255);
            int green = (int) (Math.random() * 255);
            int blue = (int) (Math.random() * 255);
            g.setColor(new Color(red, green, blue));
            g.drawOval(x, y, 1, 0);
        }
    }
    // set the border 
    public  static  void the setBorder (G Graphics, width Integer, Integer height) {
        g.setColor(Color.LIGHT_GRAY);
        g.drawRect(1, 1, width - 2, height - 2);
    }
    // draw line interference 
    public  static  void drawRandomLine (G Graphics, width Integer, Integer height) {
        g.setColor(Color.GREEN);
        for (int i = 0; i < 5; i++) {
            int x1 = new Random().nextInt(width);
            int y1 = new Random().nextInt(height);
            int x2 = new Random().nextInt(width);
            int y2 = new Random().nextInt(height);
            g.drawLine(x1, y1, x2, y2);
        }
    }
    // random number generation 
    public  static String drawRandomNum (the Graphics2D G) {
         // set the font color 
        g.setColor (Color.RED);
         // set the font style 
        g.setFont ( new new the Font ( "Arial", Font.BOLD, 26 is ) );
        Rand4 String = "" ;
         int X =. 5; // location of the font 
        for ( int I = 0; I <. 4; I ++) { // generates four random characters 
            int Degree = new new . The Random () the nextInt () 30% ; // rotation angle 
            int index = new new the Random () the nextInt (STR_NUM.length ()).;
            String ch = STR_NUM.charAt(index) + "";
            rand4 + = ch;
            g.rotate(degree * Math.PI / 180, x, 20);
            g.drawString(ch, x, 30);
            g.rotate(-degree * Math.PI / 180, x, 20);
            X + = 24; // Font position right 15px 
        }
         return rand4;
    }
    // ==== two-dimensional code generation tool method ====================================== = //