001/*
002 * The contents of this file are subject to the terms of the Common Development and
003 * Distribution License (the License). You may not use this file except in compliance with the
004 * License.
005 *
006 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
007 * specific language governing permission and limitations under the License.
008 *
009 * When distributing Covered Software, include this CDDL Header Notice in each file and include
010 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
011 * Header, with the fields enclosed by brackets [] replaced by your own identifying
012 * information: "Portions Copyright [year] [name of copyright owner]".
013 *
014 * Copyright 2014-2015 ForgeRock AS.
015 */
016package org.opends.server.backends.pluggable.spi;
017
018/**
019 * Function performing a read operation.
020 *
021 * @param <T>
022 *          type of the value that is read and returned by this read operation
023 */
024// @FunctionalInterface
025public interface ReadOperation<T>
026{
027  /**
028   * Executes a read operation, and returns the read value.
029   *
030   * @param txn
031   *          the read transaction where to execute the read operation
032   * @return the read value
033   * @throws Exception
034   *           if a problem occurs with the underlying storage engine
035   */
036  T run(ReadableTransaction txn) throws Exception;
037}