org.springframework.boot.availability.ApplicationAvailability Maven / Gradle / Ivy
/*
* Copyright 2012-2020 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.availability;
import org.springframework.context.ApplicationContext;
/**
* Provides {@link AvailabilityState availability state} information for the application.
*
* Components can inject this class to get the current state information. To update the
* state of the application an {@link AvailabilityChangeEvent} should be
* {@link ApplicationContext#publishEvent published} to the application context with
* directly or via {@link AvailabilityChangeEvent#publish}.
*
* @author Brian Clozel
* @author Phillip Webb
* @since 2.3.0
*/
public interface ApplicationAvailability {
/**
* Return the {@link LivenessState} of the application.
* @return the liveness state
*/
default LivenessState getLivenessState() {
return getState(LivenessState.class, LivenessState.BROKEN);
}
/**
* Return the {@link ReadinessState} of the application.
* @return the readiness state
*/
default ReadinessState getReadinessState() {
return getState(ReadinessState.class, ReadinessState.REFUSING_TRAFFIC);
}
/**
* Return {@link AvailabilityState} information for the application.
* @param the state type
* @param stateType the state type
* @param defaultState the default state to return if no event of the given type has
* been published yet (must not be {@code null}.
* @return the readiness state
* @see #getState(Class)
*/
S getState(Class stateType, S defaultState);
/**
* Return {@link AvailabilityState} information for the application.
* @param the state type
* @param stateType the state type
* @return the readiness state or {@code null} if no event of the given type has been
* published yet
* @see #getState(Class, AvailabilityState)
*/
S getState(Class stateType);
/**
* Return the last {@link AvailabilityChangeEvent} received for a given state type.
* @param the state type
* @param stateType the state type
* @return the readiness state or {@code null} if no event of the given type has been
* published yet
*/
AvailabilityChangeEvent getLastChangeEvent(Class stateType);
}