Android应用中怎么与Apache Tomcat服务器实现数据交互

package com.Servlet;  import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;  import java.io.PrintWriter; import java.sql.Connection; import java.sql.ResultSet; import java.sql.Statement; import com.DBTool.DBUtil;  @WebServlet("/Servlet") public class Login extends HttpServlet {   private static final long serialVersionUID = L;          public Login() {     super();     // TODO Auto-generated constructor stub   }      protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {     // TODO Auto-generated method stub     response.getWriter().append("Served at: ").append(request.getContextPath());   }       protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {     String ID = request.getParameter("ID");      String PW= request.getParameter("PW");     boolean type=false;     response.setContentType("text/html; charset=UTF-8");     PrintWriter out = response.getWriter();     try     {       Connection con=DBUtil.getConnection();       Statement stmt=con.createStatement();       //mysql数据库中的数据表，表名叫：demotable ，需要自己预先在数据库中进行创建，包含相应的字段和记录。       String sql="select * from mysql.demotable where uid="+ID+" and pwd="+PW;       ResultSet rs=stmt.executeQuery(sql);       while(rs.next())       {         type=true;       }     }     catch(Exception ex)     {       ex.printStackTrace();     }     finally     {       DBUtil.Close();       out.print(type);       out.flush();       out.close();     }   }  }