Java Servlet-入门

配置 servlet

<servlet>
    <servlet-name>one</servlet-name>
    <servlet-class>servletlearn.FirstServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>one</servlet-name>
    <url-pattern>/test</url-pattern>
    <url-pattern>/test1</url-pattern>
</servlet-mapping>
  
<servlet>
    <servlet-name>two</servlet-name>
    <servlet-class>servletlearn.SecondServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>two</servlet-name>
    <url-pattern>/test2</url-pattern>
</servlet-mapping>

FirstServlet.java

package servletlearn;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class FirstServlet extends HttpServlet {
    protected void service(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException {
        System.out.println("我的第一个servlet程序运行啦！！");
    }
}

SecondServlet.java

package servletlearn;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class SecondServlet extends HttpServlet {
    protected void service(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
        System.out.println("我的第二个servlet！！！");
        System.out.println("客户端浏览器类型："+req.getHeader("User-Agent"));
        res.getWriter().println("<h1>Hello Servelet!!!</h1>");
        res.getWriter().println("<h2>Hello Servelet!!!</h2>");
    }
}