core/sis-metadata/src/main/java/org/apache/sis/internal/jaxb/IdentifierMapEntry.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.sis.internal.jaxb;

import java.util.AbstractMap;
import org.opengis.metadata.Identifier;
import org.opengis.metadata.citation.Citation;
import org.apache.sis.metadata.iso.citation.Citations;

// Branch-dependent imports
import org.opengis.referencing.ReferenceIdentifier;


/**
 * An entry in {@link org.apache.sis.xml.IdentifierMap}. This class implements both the {@link AbstractMap.Entry}
 * interface (for inclusion in the set to be returned by {@link IdentifierMapAdapter#entrySet()}) and the
 * {@link Identifier} interface (for inclusion in the {@link IdentifierMapAdapter#identifiers} collection).
 *
 * @author  Martin Desruisseaux (Geomatys)
 * @version 0.5
 * @since   0.3
 * @module
 */
final class IdentifierMapEntry extends AbstractMap.SimpleEntry<Citation,String> implements ReferenceIdentifier {
    /**
     * For cross-version compatibility.
     */
    private static final long serialVersionUID = 5159620102001638970L;

    /**
     * Creates a new entry for the given authority and code.
     */
    IdentifierMapEntry(final Citation authority, final String code) {
        super(authority, code);
    }

    /**
     * Returns the identifier namespace, which is the key of this entry.
     */
    @Override
    public Citation getAuthority() {
        return getKey();
    }

    /**
     * Returns the identifier code, which is the value of this entry.
     */
    @Override
    public String getCode() {
        return getValue();
    }

    /**
     * Infers a code space from the authority.
     *
     * @return the code space, or {@code null} if none.
     *
     * @since 0.5
     */
    @Override
    public String getCodeSpace() {
        return Citations.toCodeSpace(getAuthority());
    }

    /**
     * Returns {@code null} since this class does not hold version information.
     *
     * @return {@code null}.
     *
     * @since 0.5
     */
    @Override
    public String getVersion() {
        return null;
    }

    /**
     * Same than the above, but as an immutable entry. We use this implementation when the
     * entry has been created on-the-fly at iteration time rather than being stored in the
     * identifier collection.
     */
    static final class Immutable extends AbstractMap.SimpleImmutableEntry<Citation,String> implements ReferenceIdentifier {
        private static final long serialVersionUID = -6857931598565368465L;
        Immutable(Citation authority, String code) {super(authority, code);}
        @Override public Citation            getAuthority()   {return getKey();}
        @Override public String              getCode()        {return getValue();}
        @Override public String              getCodeSpace()   {return Citations.toCodeSpace(getAuthority());}
        @Override public String              getVersion()     {return null;}
    }
}