[BAEL-9350] Register ServletContextListener in Spring Boot

 - implement two different ways of registering a custom ServletContextListener

Author: martin-blazevic

spring-boot-modules/spring-boot-mvc-5/src/main/java/com/baeldung/servletcontextlistener/CustomLifecycleLoggingListener.java

@@ -0,0 +1,23 @@
+package com.baeldung.servletcontextlistener;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import jakarta.servlet.ServletContextEvent;
+import jakarta.servlet.ServletContextListener;
+
+// Annotate with @WebListener if using @ServletComponentScan in ServletContextListenerApplication
+public class CustomLifecycleLoggingListener implements ServletContextListener {
+
+    private final Logger log = LoggerFactory.getLogger(CustomLifecycleLoggingListener.class);
+
+    @Override
+    public void contextInitialized(ServletContextEvent sce) {
+        log.info("Application started");
+    }
+
+    @Override
+    public void contextDestroyed(ServletContextEvent sce) {
+        log.info(" Application stopped");
+    }
+}

spring-boot-modules/spring-boot-mvc-5/src/main/java/com/baeldung/servletcontextlistener/CustomListenerConfiguration.java

@@ -0,0 +1,14 @@
+package com.baeldung.servletcontextlistener;
+
+import org.springframework.boot.web.servlet.ServletListenerRegistrationBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class CustomListenerConfiguration {
+
+    @Bean
+    public ServletListenerRegistrationBean<CustomLifecycleLoggingListener> lifecycleListener() {
+        return new ServletListenerRegistrationBean<>(new CustomLifecycleLoggingListener());
+    }
+}

spring-boot-modules/spring-boot-mvc-5/src/main/java/com/baeldung/servletcontextlistener/ServletContextListenerApplication.java

@@ -0,0 +1,13 @@
+package com.baeldung.servletcontextlistener;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+// @ServletComponentScan enables scanning for servlet components such as @WebListener, @WebFilter, and @WebServlet.
+public class ServletContextListenerApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(ServletContextListenerApplication.class, args);
+    }
+}