DynamicPropertyBasedPoolStrategy.java

/*
 *
 * Copyright 2014 Netflix, 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.netflix.ribbon.transport.netty;

import com.netflix.config.DynamicProperty;

import io.reactivex.netty.client.MaxConnectionsBasedStrategy;

/**
 * A {@link MaxConnectionsBasedStrategy} that resize itself based on callbacks from
 * {@link DynamicProperty}
 * 
 * @author awang
 *
 */
public class DynamicPropertyBasedPoolStrategy extends MaxConnectionsBasedStrategy {

    private final DynamicProperty poolSizeProperty;
    
    public DynamicPropertyBasedPoolStrategy(final int maxConnections, String propertyName) {
        super(maxConnections);
        poolSizeProperty = DynamicProperty.getInstance(propertyName);
        setMaxConnections(poolSizeProperty.getInteger(maxConnections));
        poolSizeProperty.addCallback(new Runnable() {
            @Override
            public void run() {
                setMaxConnections(poolSizeProperty.getInteger(maxConnections));
            };
        });
    }
    
    protected void setMaxConnections(int max) {
        int diff = max - getMaxConnections();
        incrementMaxConnections(diff);
    }
}