pulsar-client-admin-api/src/main/java/org/apache/pulsar/policies/data/loadbalancer/ResourceUsage.java

/**
 * 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.pulsar.policies.data.loadbalancer;

import lombok.EqualsAndHashCode;

/**
 * POJO used to represent any system specific resource usage this is the format that load manager expects it in.
 */
@EqualsAndHashCode
public class ResourceUsage {
    public final double usage;
    public final double limit;

    public ResourceUsage(double usage, double limit) {
        this.usage = usage;
        this.limit = limit;
    }

    public ResourceUsage() {
        this(0, 0);
    }

    /**
     * this may be wrong since we are comparing available and not the usage.
     *
     * @param o
     * @return
     */
    public int compareTo(ResourceUsage o) {
        double required = o.limit - o.usage;
        double available = limit - usage;
        return Double.compare(available, required);
    }

    public float percentUsage() {
        float proportion = 0;
        if (limit > 0) {
            proportion = ((float) usage) / ((float) limit);
        }
        return proportion * 100;
    }
}