/*
* Copyright 2012-2017 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
*
* http://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.context.properties.source;
import java.util.function.Predicate;
import org.springframework.util.Assert;
/**
* The state of content from a {@link ConfigurationPropertySource}.
*
* @author Phillip Webb
* @since 2.0.0
*/
public enum ConfigurationPropertyState {
/**
* The {@link ConfigurationPropertySource} has at least one matching
* {@link ConfigurationProperty}.
*/
PRESENT,
/**
* The {@link ConfigurationPropertySource} has no matching
* {@link ConfigurationProperty ConfigurationProperties}.
*/
ABSENT,
/**
* It's not possible to determine if {@link ConfigurationPropertySource} has matching
* {@link ConfigurationProperty ConfigurationProperties} or not.
*/
UNKNOWN;
/**
* Search the given iterable using a predicate to determine if content is
* {@link #PRESENT} or {@link #ABSENT}.
* @param <T> the data type
* @param source the source iterable to search
* @param predicate the predicate used to test for presence
* @return {@link #PRESENT} if the iterable contains a matching item, otherwise
* {@link #ABSENT}.
*/
static <T> ConfigurationPropertyState search(Iterable<T> source,
Predicate<T> predicate) {
Assert.notNull(source, "Source must not be null");
Assert.notNull(predicate, "Predicate must not be null");
for (T item : source) {
if (predicate.test(item)) {
return PRESENT;
}
}
return ABSENT;
}
}