org.springframework.boot.autoconfigure.condition.OnResourceCondition 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.List;
import org.springframework.boot.autoconfigure.condition.ConditionMessage.Style;
import org.springframework.context.annotation.Condition;
import org.springframework.context.annotation.ConditionContext;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.type.AnnotatedTypeMetadata;
import org.springframework.util.Assert;
import org.springframework.util.MultiValueMap;
/**
* {@link Condition} that checks for specific resources.
*
* @author Dave Syer
* @see ConditionalOnResource
*/
@Order(Ordered.HIGHEST_PRECEDENCE + 20)
class OnResourceCondition extends SpringBootCondition {
@Override
public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
MultiValueMap attributes = metadata
.getAllAnnotationAttributes(ConditionalOnResource.class.getName(), true);
ResourceLoader loader = context.getResourceLoader();
List locations = new ArrayList<>();
collectValues(locations, attributes.get("resources"));
Assert.isTrue(!locations.isEmpty(),
"@ConditionalOnResource annotations must specify at least one resource location");
List missing = new ArrayList<>();
for (String location : locations) {
String resource = context.getEnvironment().resolvePlaceholders(location);
if (!loader.getResource(resource).exists()) {
missing.add(location);
}
}
if (!missing.isEmpty()) {
return ConditionOutcome.noMatch(ConditionMessage.forCondition(ConditionalOnResource.class)
.didNotFind("resource", "resources").items(Style.QUOTE, missing));
}
return ConditionOutcome.match(ConditionMessage.forCondition(ConditionalOnResource.class)
.found("location", "locations").items(locations));
}
private void collectValues(List names, List