NamespaceBundleStatsComparator.java

/**
 * Copyright 2016 Yahoo Inc.
 *
 * Licensed 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.yahoo.pulsar.common.policies.data.loadbalancer;

import java.util.Comparator;
import java.util.Map;

import com.yahoo.pulsar.common.policies.data.loadbalancer.SystemResourceUsage.ResourceType;

/**
 */
public class NamespaceBundleStatsComparator implements Comparator<String> {
    Map<String, NamespaceBundleStats> map;
    ResourceType resType;

    public NamespaceBundleStatsComparator(Map<String, NamespaceBundleStats> map, ResourceType resType) {
        this.map = map;
        this.resType = resType;
    }

    // sort in reverse order, maximum loaded should be on top
    public int compare(String a, String b) {
        int result = 0;
        if (this.resType == ResourceType.CPU) {
            result = map.get(a).compareByMsgRate(map.get(b));
        } else if (this.resType == ResourceType.Memory) {
            result = map.get(a).compareByTopicConnections(map.get(b));
        } else if (this.resType == ResourceType.BandwidthIn) {
            result = map.get(a).compareByBandwidthIn(map.get(b));
        } else if (this.resType == ResourceType.BandwidthOut) {
            result = map.get(a).compareByBandwidthOut(map.get(b));
        } else {
            result = map.get(a).compareTo(map.get(b));
        }

        if (result > 0) {
            return -1;
        } else {
            return 1;
        }
    }
}