org.springframework.boot.autoconfigure.condition.ResourceCondition Maven / Gradle / Ivy
/*
* Copyright 2012-2019 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.autoconfigure.condition;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.springframework.boot.autoconfigure.condition.ConditionMessage.Builder;
import org.springframework.boot.autoconfigure.condition.ConditionMessage.Style;
import org.springframework.context.annotation.ConditionContext;
import org.springframework.core.io.Resource;
import org.springframework.core.type.AnnotatedTypeMetadata;
/**
* {@link SpringBootCondition} used to check if a resource can be found using a
* configurable property and optional default location(s).
*
* @author Stephane Nicoll
* @author Phillip Webb
* @author Madhura Bhave
* @since 1.3.0
*/
public abstract class ResourceCondition extends SpringBootCondition {
private final String name;
private final String property;
private final String[] resourceLocations;
/**
* Create a new condition.
* @param name the name of the component
* @param property the configuration property
* @param resourceLocations default location(s) where the configuration file can be
* found if the configuration key is not specified
* @since 2.0.0
*/
protected ResourceCondition(String name, String property, String... resourceLocations) {
this.name = name;
this.property = property;
this.resourceLocations = resourceLocations;
}
@Override
public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
if (context.getEnvironment().containsProperty(this.property)) {
return ConditionOutcome.match(startConditionMessage().foundExactly("property " + this.property));
}
return getResourceOutcome(context, metadata);
}
/**
* Check if one of the default resource locations actually exists.
* @param context the condition context
* @param metadata the annotation metadata
* @return the condition outcome
*/
protected ConditionOutcome getResourceOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
List found = new ArrayList<>();
for (String location : this.resourceLocations) {
Resource resource = context.getResourceLoader().getResource(location);
if (resource != null && resource.exists()) {
found.add(location);
}
}
if (found.isEmpty()) {
ConditionMessage message = startConditionMessage().didNotFind("resource", "resources").items(Style.QUOTE,
Arrays.asList(this.resourceLocations));
return ConditionOutcome.noMatch(message);
}
ConditionMessage message = startConditionMessage().found("resource", "resources").items(Style.QUOTE, found);
return ConditionOutcome.match(message);
}
protected final Builder startConditionMessage() {
return ConditionMessage.forCondition("ResourceCondition", "(" + this.name + ")");
}
}