view层：jsp展示和传输数据：
控制器层：
servlet：多个请求调用一个servlet：
@WebServlet(name ="CustomerServlet",urlPatterns ="*.do")
public class CustomerServletextends HttpServlet {
// protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// String method = request.getParameter("method");
// switch (method){
// case "add":add(request,response);break;
// case "query":query(request,response);break;
// case "delete":delete(request,response);break;
// }
// }
protected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
//1.获取ServletPath：/edit.do或add.do
String servletPath = request.getServletPath();
//2.去除/和.do,得到类似于edit和add这样的字符串
try {
String methodName = servletPath.substring(5);
methodName = methodName.substring(0,methodName.length()-3);
System.out.println(methodName);
//3.利用反射获取methodName对应的方法
Method method = getClass().getDeclaredMethod(methodName,HttpServletRequest.class,HttpServletResponse.class);
//4.利用反射调用对应的方法
method.invoke(this,request,response);
}
catch (Exception e) {
request.getRequestDispatcher("/WEB-INF/error.jsp").forward(request,response);
// e.printStackTrace();
}
}
private void add(HttpServletRequest request,HttpServletResponse response)throws ServletException{
System.out.println("add");
}
private void query(HttpServletRequest request,HttpServletResponse response)throws ServletException{
System.out.println("query");
}
private void delete(HttpServletRequest request,HttpServletResponse response)throws ServletException{
System.out.println("delete");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
doPost(request,response);
}
}
数据层：
JDBC工具采用DBUtils
数据库连接池为：c3p0
通过DAO设计模型，反射，泛型，构成后台操作数据库代码的通用性：
大大增加后台操作数据库代码的重用性
