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.
/**
 * 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.config;

An implementation of DynamicDoubleProperty that caches the primitive value whenever it is changed. This can give improved performance due to avoiding the unboxing, at the expense of additional memory usage. 
Author:
Mike Smith/**
 * An implementation of {@link DynamicDoubleProperty} that caches the primitive value whenever it is changed.
 *
 * This can give improved performance due to avoiding the unboxing, at the expense of additional
 * memory usage.
 *
 * @author Mike Smith
 *
 */
public class CachedDynamicDoubleProperty extends DynamicDoubleProperty {

    protected volatile double primitiveValue;

    public CachedDynamicDoubleProperty(String propName, double defaultValue) {
        super(propName, defaultValue);

        // Set the initial value of the cached primitive value.
        this.primitiveValue = chooseValue();
    }

    @Override
    protected void propertyChanged() {
        // Update the cached primitive value when the property is changed.
        this.primitiveValue = chooseValue();
    }

    
Get the current value from the underlying DynamicProperty
Returns:
/**
     * Get the current value from the underlying DynamicProperty
     *
     * @return
     */
    protected double chooseValue() {
        return prop.getDouble(defaultValue).doubleValue();
    }

    
Get the current cached value.
Returns:
/**
     * Get the current cached value.
     *
     * @return
     */
    @Override
    public double get() {
        return primitiveValue;
    }

    @Override
    public Double getValue() {
        return get();
    }
}