org.apache.hadoop.hdfs.server.balancer.Matcher 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.balancer;
import org.apache.hadoop.net.NetworkTopology;
import org.apache.hadoop.net.Node;
/** A matcher interface for matching nodes. */
public interface Matcher {
/** Given the cluster topology, does the left node match the right node? */
public boolean match(NetworkTopology cluster, Node left, Node right);
/** Match datanodes in the same node group. */
public static final Matcher SAME_NODE_GROUP = new Matcher() {
@Override
public boolean match(NetworkTopology cluster, Node left, Node right) {
return cluster.isOnSameNodeGroup(left, right);
}
@Override
public String toString() {
return "SAME_NODE_GROUP";
}
};
/** Match datanodes in the same rack. */
public static final Matcher SAME_RACK = new Matcher() {
@Override
public boolean match(NetworkTopology cluster, Node left, Node right) {
return cluster.isOnSameRack(left, right);
}
@Override
public String toString() {
return "SAME_RACK";
}
};
/** Match any datanode with any other datanode. */
public static final Matcher ANY_OTHER = new Matcher() {
@Override
public boolean match(NetworkTopology cluster, Node left, Node right) {
return left != right;
}
@Override
public String toString() {
return "ANY_OTHER";
}
};
}