protected?void?doGet(HttpServletRequest?request,
			HttpServletResponse?response)?throws?ServletException,?IOException?{

		Random?random?=?new?Random();
		int?colorRandoMin?=?200;
		int?colorRandoMax?=?255;

		//?int?randomNum?=?random.nextInt(randoMax)?%?(randoMax?-?randoMin?+?1)
		//?+?randoMin;

		//?生成驗證碼
		BufferedImage?bufferedImage?=?new?BufferedImage(68,?23,
				BufferedImage.TYPE_INT_RGB);

		//?繪圖上上下文對象
		Graphics?graphics?=?bufferedImage.createGraphics();

		//?畫個背景
		//?三元色數值隨機產生
		//?設置顏色
		graphics.setColor(new?Color(random.nextInt(colorRandoMax
				-?colorRandoMin?+?1)
				+?colorRandoMin,?random.nextInt(colorRandoMax?-?colorRandoMin
				+?1)
				+?colorRandoMin,?random.nextInt(colorRandoMax?-?colorRandoMin
				+?1)
				+?colorRandoMin));
		//?填充矩形
		graphics.fillRect(0,?0,?68,?23);

		//?繪制文字
		char[]?valChar?=?"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
				.toCharArray();

		//?索引
		int?index?=?0;
		int?len?=?valChar.length;

		//?用來拼接字符存儲進session
		StringBuilder?sb?=?new?StringBuilder();

		//?重設文字顏色范圍
		colorRandoMin?=?1;
		colorRandoMax?=?130;

		//?生成4個字符
		for?(int?i?=?0;?i?<?4;?i++)?{

			//?生成索引
			index?=?random.nextInt(len);

			graphics.setFont(new?Font("Arial",?Font.BOLD,?16));

			//?設置文字顏色
			graphics.setColor(new?Color(random.nextInt(colorRandoMax
					-?colorRandoMin?+?1)
					+?colorRandoMin,?random.nextInt(colorRandoMax
					-?colorRandoMin?+?1)
					+?colorRandoMin,?random.nextInt(colorRandoMax
					-?colorRandoMin?+?1)
					+?colorRandoMin));
			//?繪制文字
			graphics.drawString(valChar[index]?+?"",?i?*?15?+?5,?18);

			sb.append(valChar[index]);
		}

		//?存儲在session中
		request.getSession().setAttribute("validateCode",?sb.toString());
		sb?=?null;

		//?輸入驗證碼圖
		OutputStream?out?=?response.getOutputStream();
		ImageIO.write(bufferedImage,?"jpg",?out);

		//?刷新并關閉輸出流
		out.flush();
		out.close();

	}