mirror of
https://github.com/spring-projects/spring-boot.git
synced 2024-09-03 04:26:12 +08:00
Document how to obtain ServletContext with an embedded container setup
Closes gh-24561
This commit is contained in:
parent
708e57eafb
commit
d240e293db
@ -818,6 +818,17 @@ Usually a `TomcatServletWebServerFactory`, `JettyServletWebServerFactory`, or `U
|
||||
NOTE: You usually do not need to be aware of these implementation classes.
|
||||
Most applications are auto-configured, and the appropriate `ApplicationContext` and `ServletWebServerFactory` are created on your behalf.
|
||||
|
||||
In an embedded container setup, the `ServletContext` is set as part of server startup which happens during application context initialization.
|
||||
Because of this beans in the `ApplicationContext` cannot be reliably initialized with a `ServletContext`.
|
||||
One way to get around this is to inject `ApplicationContext` as a dependency of the bean and access the `ServletContext` only when it is needed.
|
||||
Another way is to use a callback once the server has started.
|
||||
This can be done using an `ApplicationListener` which listens for the `ApplicationStartedEvent` as follows:
|
||||
|
||||
[source,java,indent=0,subs="verbatim"]
|
||||
----
|
||||
include::{docs-java}/features/developingwebapplications/embeddedcontainer/applicationcontext/MyDemoBean.java[]
|
||||
----
|
||||
|
||||
|
||||
|
||||
[[features.developing-web-applications.embedded-container.customizing]]
|
||||
|
@ -0,0 +1,36 @@
|
||||
/*
|
||||
* Copyright 2012-2022 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* https://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package org.springframework.boot.docs.features.developingwebapplications.embeddedcontainer.applicationcontext;
|
||||
|
||||
import javax.servlet.ServletContext;
|
||||
|
||||
import org.springframework.boot.context.event.ApplicationStartedEvent;
|
||||
import org.springframework.context.ApplicationContext;
|
||||
import org.springframework.context.ApplicationListener;
|
||||
import org.springframework.web.context.WebApplicationContext;
|
||||
|
||||
public class MyDemoBean implements ApplicationListener<ApplicationStartedEvent> {
|
||||
|
||||
private ServletContext servletContext;
|
||||
|
||||
@Override
|
||||
public void onApplicationEvent(ApplicationStartedEvent event) {
|
||||
ApplicationContext applicationContext = event.getApplicationContext();
|
||||
this.servletContext = ((WebApplicationContext) applicationContext).getServletContext();
|
||||
}
|
||||
|
||||
}
|
Loading…
Reference in New Issue
Block a user