org.apache.hadoop.hdfs.server.namenode.INodeId Maven / Gradle / Ivy
/**
* 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.hadoop.hdfs.server.namenode;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.util.SequentialNumber;
/**
* An id which uniquely identifies an inode. Id 1 to 16384 are reserved for
* potential future usage. The id won't be recycled and is not expected to wrap
* around in a very long time. Root inode id is always 16385. Id 0 is used for
* backward compatibility support.
*/
@InterfaceAudience.Private
public class INodeId extends SequentialNumber {
/**
* The last reserved inode id. InodeIDs are allocated from LAST_RESERVED_ID +
* 1.
*/
public static final long LAST_RESERVED_ID = 1 << 14; // 16384
public static final long ROOT_INODE_ID = LAST_RESERVED_ID + 1; // 16385
public static final long INVALID_INODE_ID = -1;
INodeId() {
super(ROOT_INODE_ID);
}
}