/*
 * 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.jackrabbit.oak.segment;

import java.util.Iterator;

import org.jetbrains.annotations.NotNull;

/**
 * An implementation of a record number to offset table that assumes that a
 * record number is also a valid offset in the segment. This implementation is
 * useful when an instance of a table has still to be provided, but record
 * numbers have no logical semantics (e.g. for bulk segments).
 * <p>
 * This implementation is trivially thread-safe.
 */
class IdentityRecordNumbers implements RecordNumbers {

    @Override
    public int getOffset(int recordNumber) {
        return recordNumber;
    }

    @NotNull
    @Override
    public Iterator<Entry> iterator() {
        throw new UnsupportedOperationException("invalid usage of the record-number-to-offset table");
    }

}
