com.lcw.one.common.servlet.ValidateCodeServlet.java Source code

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Here is the source code for com.lcw.one.common.servlet.ValidateCodeServlet.java

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/**
 * Copyright &copy; 2012-2013 <a href="https://github.com/thinkgem/jeesite">JeeSite</a> All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 */
package com.lcw.one.common.servlet;

import org.apache.commons.lang.math.NumberUtils;
import org.apache.commons.lang3.StringUtils;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;

/**
 * ????
 * @author ThinkGem
 * @version 2013-5-19
 */
@SuppressWarnings("serial")
public class ValidateCodeServlet extends HttpServlet {

    public static final String VALIDATE_CODE = "validateCode";

    private int w = 70;
    private int h = 26;

    public ValidateCodeServlet() {
        super();
    }

    public void destroy() {
        super.destroy();
    }

    public static boolean validate(HttpServletRequest request, String validateCode) {
        String code = (String) request.getSession().getAttribute(VALIDATE_CODE);
        return validateCode.toUpperCase().equals(code);
    }

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String validateCode = request.getParameter(VALIDATE_CODE); // AJAX??true
        if (StringUtils.isNotBlank(validateCode)) {
            response.getOutputStream().print(validate(request, validateCode) ? "true" : "false");
        } else {
            this.doPost(request, response);
        }
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        createImage(request, response);
    }

    private void createImage(HttpServletRequest request, HttpServletResponse response) throws IOException {

        response.setHeader("Pragma", "no-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expires", 0);
        response.setContentType("image/jpeg");

        /*
         * ??
         */
        String width = request.getParameter("width");
        String height = request.getParameter("height");
        if (StringUtils.isNumeric(width) && StringUtils.isNumeric(height)) {
            w = NumberUtils.toInt(width);
            h = NumberUtils.toInt(height);
        }

        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
        Graphics g = image.getGraphics();

    }

}