JSP学习笔记（8）_Servlet（1）
1.结构体系
HttpServlet <---(子类)--- GenericServlet(抽象类) ---(实现)---> (1)(2)(3)
(1)Servlet (interfance)
(2)ServletConfig (interfance)
(3)Serializable (interfance) 序列化接口
2.特点
跨平台，可移植性
3.效率
比JSP效率高
4.简单实现
public class Test01 implements Servlet{方法以及作用：
public void destroy() {
// TODO Auto-generated method stub
System.out.println("killed!!!");
}
public ServletConfig getServletConfig() {
// TODO Auto-generated method stub
return null;
}
public String getServletInfo() {
// TODO Auto-generated method stub
return null;
}
public void init(ServletConfig config) throws ServletException {
// TODO Auto-generated method stub
System.out.println("出现了!!");
}
public void service(ServletRequest req, ServletResponse res)
throws ServletException, IOException {
// TODO Auto-generated method stub
//System.out.println("服务中...");
HttpServletRequest request = (HttpServletRequest)req;
HttpServletResponse response = (HttpServletResponse)res;
String username = request.getParameter("username");
PrintWriter out = response.getWriter();
out.println("<html><head></head><body>");
out.println("<h1>hello "+username+"!</h1>");
out.println("</body></html>");
}
}
public void destroy()// 当服务器内存不足而导致servlet对象被调度或者关闭服务器时，serlet对象销毁前执行
public ServletConfig getServletConfig()// 用于获取config对象public String getServletInfo()// 用于获取servlet的说明信息public void init(ServletConfig config) throws ServletException// 用于执行对象创建后{构造器执行后}的初始化操作，在整个Servlet对象的生命周期中运行且只运行一次public void service(ServletRequest req, ServletResponse res)throws ServletException, IOException// 用于对外提供服务,响应客户请求[URL],该方法以多线程的方式对外提供服务,服务完毕则常驻内存