org.neo4j.storageengine.api.lock.ResourceLocker Maven / Gradle / Ivy

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/*
 * Copyright (c) 2002-2016 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */
package org.neo4j.storageengine.api.lock;

public interface ResourceLocker
{
    /**
     * Can be grabbed when no other client holds locks on the relevant resources. No other clients can hold locks
     * while one client holds an exclusive lock. If the lock cannot be acquired,
     * behavior is specified by the {@link WaitStrategy} for the given {@link ResourceType}.
     */
    void acquireExclusive( ResourceType resourceType, long resourceId ) throws AcquireLockTimeoutException;

    ResourceLocker NONE = new ResourceLocker()
    {
        @Override
        public void acquireExclusive( ResourceType resourceType, long resourceId ) throws AcquireLockTimeoutException
        {
            throw new UnsupportedOperationException( "Unexpected call to lock a resource " + resourceType +
                    " " + resourceId );
        }
    };
}