在web应用中Servlet的应用比较多，最开始的web应用就是全部以servlet来实现的，后来出现了Struts、Struts2，到今天应用非常广泛的SpringMvc，这些web mvc框架比原来的servlet功能更加强大，开发效率而更高，但是实际上这些框架底层都是servlet在做支撑。今天我们学习如何在SpringBoot添加Servlet的应用。

一.编写Servlet继承HttpServlet

package com.maxbill.core.webbox.servlet;

import org.apache.log4j.Logger;

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;

/** * @功能 自定义servlet * @作者 zuoshuai(MaxBill) * @日期 2017/7/6 * @时间 14:57 * @备注 MyServlet */ public class MyServlet extends HttpServlet {

Logger log = Logger.getLogger(MyServlet.class);

protected void doGet(HttpServletRequest request, HttpServletResponse response) 

  throws ServletException, IOException { log.info("servlet通过get方式请求完成..."); }

}

这里只实现了doGet请求，post、put等请求同理实现即可。

二.注册servlet到启动类

package com.maxbill;

import com.maxbill.core.webbox.servlet.MyServlet; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.web.servlet.ServletRegistrationBean; import org.springframework.context.annotation.Bean;

@SpringBootApplication public class MaxbillApplication {

/\*\*
 \* 注册Servlet
 \*/
@Bean
public ServletRegistrationBean MyServlet1(){
    return new ServletRegistrationBean(new MyServlet(),"/servlet/\*");
}

public static void main(String\[\] args) {
    SpringApplication.run(MaxbillApplication.class, args);
}

}

三.使用注解注册servlet

首先在servlet上增加@WebServlet

@WebServlet(urlPatterns = "/servlet/*", description = "") public class MyServlet extends HttpServlet {

Logger log = Logger.getLogger(MyServlet.class);

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    log.info("servlet通过get方式请求完成...");
}

}

然后在启动类中增加@ServletComponentScan，使项目中的servlet能够被扫描到

package com.maxbill;

import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.web.servlet.ServletComponentScan;

@ServletComponentScan @SpringBootApplication public class MaxbillApplication {

public static void main(String\[\] args) {
    SpringApplication.run(MaxbillApplication.class, args);
}

}

启动项目测试：访问http://127.0.0.1:520/servlet

控制台日志：INFO com.maxbill.core.webbox.servlet.MyServlet:25 - servlet通过get方式请求完成...