SpringBoot整合Servlet的兩種方式

方式一：通過注解掃描方式實現

項目名稱：030-springboot-servlet-01

1.通過注解方式創建一個Servlet

在com.abc.springboot.servlet包下創建MyServlet

package com.abc.springboot.servlet;

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;

/**
 * ClassName:MyServlet
 * Package:com.abc.springboot.servlet
 * Description:

 */
@WebServlet(urlPatterns = "/myServlet")
public class MyServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.getWriter().print("My SpringBoot Servlet");
        response.getWriter().flush();
        response.getWriter().close();
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request,response);
    }
}

2.在主應用程序Application類上添加@ServletComponentScan("com.abc.springboot.servlet")

package com.abc.springboot;

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

@SpringBootApplication
@ServletComponentScan(basePackages = "com.abc.springboot.servlet")
public class Application {

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

}

3.啟動應用SpringBoot，瀏覽器訪問測試

方式二： 通過SpringBoot的配置類實現（組件注冊）

項目名稱：031-springboot-servlet-02

1.創建一個普通的Servlet

在com.abc.springboot.servlet包下創建HeServlet類

package com.abc.springboot.servlet;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * ClassName:HeServlet
 * Package:com.abc.springboot.servlet
 * Description:

 */
public class HeServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.getWriter().print("He SpringBoot Servlet");
        response.getWriter().flush();
        response.getWriter().close();
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request,response);
    }
}

2.編寫一個Spring Boot的配置類，在該類中注冊Servlet

在com.abc.springboot.config包下，創建ServletConfig配置類

package com.abc.springboot.config;

import com.abc.springboot.servlet.HeServlet;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * ClassName:ServletConfig
 * Package:com.abc.springboot.config
 * Description:

 */
@Configuration //添加@Configuration 將此類變為配置變
public class ServletConfig {

    /**
     * @Bean是一個方法級別上的注解，主要用在@Configuration注解的類里，也可以用在@Component注解的類里。添加的bean的id為方法名
     * 如下代碼相當于
     * 
     *     
     * 
     * @return
     */
    @Bean
    public ServletRegistrationBean heServletRegistrationBean() {

        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new HeServlet(),"/servlet/heServlet");

        return servletRegistrationBean;
    }
}

3.啟動應用SpringBoot，瀏覽器訪問測試