com.datastax.oss.driver.internal.core.loadbalancing.nodeset.NodeSet 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 com.datastax.oss.driver.internal.core.loadbalancing.nodeset;
import com.datastax.oss.driver.api.core.metadata.Node;
import edu.umd.cs.findbugs.annotations.NonNull;
import edu.umd.cs.findbugs.annotations.Nullable;
import java.util.Set;
import net.jcip.annotations.ThreadSafe;
/**
* A thread-safe abstraction around a map of nodes per datacenter, to facilitate node management by
* load balancing policies.
*/
@ThreadSafe
public interface NodeSet {
/**
* Adds the given node to this set.
*
* If this set was initialized with datacenter awareness, the node will be added to its
* datacenter's specific set; otherwise, the node is added to a general set containing all nodes
* in the cluster.
*
* @param node The node to add.
* @return true if the node was added, false otherwise (because it was already present).
*/
boolean add(@NonNull Node node);
/**
* Removes the node from the set.
*
* @param node The node to remove.
* @return true if the node was removed, false otherwise (because it was not present).
*/
boolean remove(@NonNull Node node);
/**
* Returns the current nodes in the given datacenter.
*
*
If this set was initialized with datacenter awareness, the returned set will contain only
* nodes pertaining to the given datacenter; otherwise, the given datacenter name is ignored and
* the returned set will contain all nodes in the cluster.
*
* @param dc The datacenter name, or null if the datacenter name is not known, or irrelevant.
* @return the current nodes in the given datacenter.
*/
@NonNull
Set dc(@Nullable String dc);
/**
* Returns the current datacenter names known to this set. If datacenter awareness has been
* disabled, this method returns an empty set.
*/
Set dcs();
}