checkmerchantloginname.java

基于struts的网上商店源码

package com.mole.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.mole.struts.dao.DBConnector;

public class checkMerchantLoginName extends HttpServlet {
	private DBConnector dbc = new DBConnector();
	private HttpServletResponse response;

	/**
	 * Constructor of the object.
	 */
	public checkMerchantLoginName() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doPost method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to
	 * post.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		this.response = response;
		String action = request.getParameter("action");
		String userName = request.getParameter("userName");
		response.setContentType("text/html");
		response.setCharacterEncoding("UTF-8");
		if (action != null && action.equals("checkusername")
				&& userName != null)
			checkMerchantName(userName);
	}

	/**
	 * Initialization of the servlet. <br>
	 * 
	 * @throws ServletException
	 *             if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

	private void checkMerchantName(String merchantName) {
		String sql = "select * from Merchant where LoginName='" + merchantName
				+ "'";
		ArrayList<Object[]> list = null;
		try {
			list = dbc.executeQuery(sql);
		} catch (Exception e) {
			e.printStackTrace();
		}
		try {
			if (list.size() == 0)
				((PrintWriter) response.getWriter()).print("0");
			else
				((PrintWriter) response.getWriter()).print("1");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}