InjectableAttributeImpl.java

/**
 * Copyright (c) Codice Foundation
 * <p>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p>
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package ddf.catalog.data.impl;

import static org.apache.commons.lang.Validate.notNull;

import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Optional;
import java.util.Set;

import javax.annotation.Nullable;

import ddf.catalog.data.InjectableAttribute;

public class InjectableAttributeImpl implements InjectableAttribute {
    private final String attribute;

    private final Set<String> metacardTypes = new HashSet<>();

    /**
     * Constructs an {@link InjectableAttributeImpl} with the given attribute name and metacard type
     * names.
     * <p>
     * If this attribute should be injected into all {@link ddf.catalog.data.MetacardType}s, then
     * {@code metacardTypes} should be null or empty.
     *
     * @param attribute     the name of the attribute that this {@code InjectableAttributeImpl}
     *                      represents, cannot be null
     * @param metacardTypes the names of the {@link ddf.catalog.data.MetacardType}s into which the
     *                      attribute named {@code attribute} should be injected, can be null
     * @throws IllegalArgumentException if {@code attribute} is null
     */
    public InjectableAttributeImpl(String attribute, @Nullable Collection<String> metacardTypes) {
        notNull(attribute, "The attribute name cannot be null.");
        this.attribute = attribute;

        Optional.ofNullable(metacardTypes)
                .ifPresent(this.metacardTypes::addAll);
    }

    @Override
    public String attribute() {
        return attribute;
    }

    @Override
    public Set<String> metacardTypes() {
        return Collections.unmodifiableSet(metacardTypes);
    }
}