g.rotate(-hudu, x, y);//为什么加减号就返回0位置了?


        Random random = new Random();
        int x = 20;
        int y = 20;
        for(int i=0;i<4;i++){

            // void rotate(double theta, double x, double y)  
            // theta 弧度
            // hudu = jiaodu * Math.PI / 180;
            // 获取正负30之间的角度
            int jiaodu = random.nextInt(60)-30;
            double hudu = jiaodu * Math.PI / 180;
            g.rotate(hudu, x, y);
            // 获取下标
            int index = random.nextInt(words.length());
            // 返回指定下标位置的字符,随机获取下标
            char ch = words.charAt(index);
            // 写字符串
            g.drawString(""+ch, x, y);

            g.rotate(-hudu, x, y);//为什么加减号就返回0位置了?
            x += 20;
        }

        // 设置颜色
        g.setColor(Color.GREEN);
        int x1,x2,y1,y2;
        // 画干扰线
        for(int i=0;i<4;i++){
            x1 = random.nextInt(width);
            y1 = random.nextInt(height);
            x2 = random.nextInt(width);
            y2 = random.nextInt(height);
            g.drawLine(x1, y1, x2, y2);
        }

        // 输出到客户端
        ImageIO.write(image, "jpg", response.getOutputStream());

这个数字你可能是hudu就是在原来基础上加上那么多,-hudu就是在原来角度上减