Servlet的体系架构
Servlet -- 接口
|
GenericServlet -- 抽象类
|
HttpServlet -- 抽象类
* GenericServlet:将Servlet接口中其他的方法做了默认空实现,只将service()方法作为抽象
* 将来定义Servlet类时,可以继承GenericServlet,实现service()方法即可
package com.test.servlet;
import javax.servlet.GenericServlet;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import java.io.IOException;
@WebServlet("/hello")
public class MyGenericServlet extends GenericServlet {
@Override
public void service(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException {
System.out.println("asdlkfjaklsdjflaksjdlk");
}
}
* HttpServlet:对http协议的一种封装,简化操作
1. 定义类继承HttpServlet
2. 复写doGet/doPost方法
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.IOException;
@WebServlet("/hello")
public class MyHttpServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("doget");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("dopost");
}
}
Servlet相关配置
1. urlpartten:Servlet访问路径
1. 一个Servlet可以定义多个访问路径 : @WebServlet({"/d4","/dd4","/ddd4"})
2. 路径定义规则:
1. /xxx 路径匹配
2. /xxx/xxx 多层路径,目录结构
4. /xxx/* 多层路径,目录结构 (优先级特别的低)
3. *.do 扩展名匹配 (虚拟路径 任何名.do 都可以访问);