userreg.java

Ajax实现GET方式注册登录

package pack;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;


public class UserReg extends HttpServlet {
    
	public void init(ServletConfig config) throws ServletException {
    }
    
    
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    	//设置接收信息的字符集
    	request.setCharacterEncoding("UTF-8");
    	//接收浏览器端提交的信息
		String name = request.getParameter("name");
		String password = request.getParameter("password");
		String email = request.getParameter("email");		
		//设置输出信息的格式及字符集，注意必须为UTF-8才可以正确解析动态生成的XML文件
        response.setContentType("text/xml; charset=UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        //创建输出流对象
        PrintWriter out = response.getWriter();
        //依据验证用户名是否已被注册
        out.println("<root>");		
		DataAccess da = new DataAccess();
		ResultSet rs = da.query("select * from Users where Name='" + name + "'");
		try {
			if(rs.next()) {//用户名存在
				out.println("<inf>" + "用户" + name + "已被注册" + "</inf>");
			} else {//用户名未被注册
				int num = da.update("insert into Users values('" + name + "','" + password + "','" + email + "')");
				if(num > 0) { //更新成功
					out.println("<inf>" + "ok" + "</inf>");
				} else {//更新不成功
					out.println("<inf>" + "注册失败" + "</inf>");
				}
			}
	    }
	    catch (Exception ex) {
	    	out.println("<inf>" + "操纵数据库失败" + "</inf>");
	    	ex.printStackTrace();
	    }
		out.println("</root>");
		out.close();
    }
    /*
     *  处理<POST> 请求方法.
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
       doGet(request, response);
    }
}