https://github.com/Netflix/Hystrix: hystrix-core
  • Netflix Open Source Development 
Copyright 2012 Netflix, Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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http://www.apache.org/licenses/LICENSE-2.0
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/**
 * Copyright 2012 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.hystrix.strategy.metrics;

import com.netflix.hystrix.HystrixCircuitBreaker;
import com.netflix.hystrix.HystrixCollapser;
import com.netflix.hystrix.HystrixCollapserKey;
import com.netflix.hystrix.HystrixCollapserMetrics;
import com.netflix.hystrix.HystrixCollapserProperties;
import com.netflix.hystrix.HystrixCommand;
import com.netflix.hystrix.HystrixCommandGroupKey;
import com.netflix.hystrix.HystrixCommandKey;
import com.netflix.hystrix.HystrixCommandMetrics;
import com.netflix.hystrix.HystrixCommandProperties;
import com.netflix.hystrix.HystrixThreadPool;
import com.netflix.hystrix.HystrixThreadPoolKey;
import com.netflix.hystrix.HystrixThreadPoolMetrics;
import com.netflix.hystrix.HystrixThreadPoolProperties;
import com.netflix.hystrix.strategy.HystrixPlugins;


Abstract class with default implementations of Factory methods for creating "Metrics Publisher" instances for getting metrics and other related data
exposed, published or otherwise retrievable by external systems such as Servo (https://github.com/Netflix/servo)
for monitoring and statistical purposes.

 See HystrixPlugins or the Hystrix GitHub Wiki for information on configuring plugins: https://github.com/Netflix/Hystrix/wiki/Plugins.

/**
 * Abstract class with default implementations of Factory methods for creating "Metrics Publisher" instances for getting metrics and other related data
 * exposed, published or otherwise retrievable by external systems such as Servo (https://github.com/Netflix/servo)
 * for monitoring and statistical purposes.
 * <p>
 * See {@link HystrixPlugins} or the Hystrix GitHub Wiki for information on configuring plugins: <a
 * href="https://github.com/Netflix/Hystrix/wiki/Plugins">https://github.com/Netflix/Hystrix/wiki/Plugins</a>.
 */
public abstract class HystrixMetricsPublisher {

    // TODO should this have cacheKey functionality like HystrixProperties does?
    // I think we do otherwise dynamically provided owner and properties won't work
    // a custom override would need the caching strategy for properties/publisher/owner etc to be in sync

    
Construct an implementation of HystrixMetricsPublisherCommand for HystrixCommand instances having key HystrixCommandKey. 
 This will be invoked once per HystrixCommandKey instance. 

Default Implementation

 Return instance of HystrixMetricsPublisherCommandDefault 
Params:
Returns:instance of HystrixMetricsPublisherCommand that will have its initialize method invoked once.
/**
     * Construct an implementation of {@link HystrixMetricsPublisherCommand} for {@link HystrixCommand} instances having key {@link HystrixCommandKey}.
     * <p>
     * This will be invoked once per {@link HystrixCommandKey} instance.
     * <p>
     * <b>Default Implementation</b>
     * <p>
     * Return instance of {@link HystrixMetricsPublisherCommandDefault}
     * 
     * @param commandKey
     *            {@link HystrixCommandKey} representing the name or type of {@link HystrixCommand}
     * @param commandGroupKey
     *            {@link HystrixCommandGroupKey} of {@link HystrixCommand}
     * @param metrics
     *            {@link HystrixCommandMetrics} instance tracking metrics for {@link HystrixCommand} instances having the key as defined by {@link HystrixCommandKey}
     * @param circuitBreaker
     *            {@link HystrixCircuitBreaker} instance for {@link HystrixCommand} instances having the key as defined by {@link HystrixCommandKey}
     * @param properties
     *            {@link HystrixCommandProperties} instance for {@link HystrixCommand} instances having the key as defined by {@link HystrixCommandKey}
     * @return instance of {@link HystrixMetricsPublisherCommand} that will have its <code>initialize</code> method invoked once.
     */
    public HystrixMetricsPublisherCommand getMetricsPublisherForCommand(HystrixCommandKey commandKey, HystrixCommandGroupKey commandGroupKey, HystrixCommandMetrics metrics, HystrixCircuitBreaker circuitBreaker, HystrixCommandProperties properties) {
        return new HystrixMetricsPublisherCommandDefault(commandKey, commandGroupKey, metrics, circuitBreaker, properties);
    }

    
Construct an implementation of HystrixMetricsPublisherThreadPool for HystrixThreadPool instances having key HystrixThreadPoolKey. 
 This will be invoked once per HystrixThreadPoolKey instance. 

Default Implementation

 Return instance of HystrixMetricsPublisherThreadPoolDefault 
Params:
Returns:instance of HystrixMetricsPublisherThreadPool that will have its initialize method invoked once.
/**
     * Construct an implementation of {@link HystrixMetricsPublisherThreadPool} for {@link HystrixThreadPool} instances having key {@link HystrixThreadPoolKey}.
     * <p>
     * This will be invoked once per {@link HystrixThreadPoolKey} instance.
     * <p>
     * <b>Default Implementation</b>
     * <p>
     * Return instance of {@link HystrixMetricsPublisherThreadPoolDefault}
     * 
     * @param threadPoolKey
     *            {@link HystrixThreadPoolKey} representing the name or type of {@link HystrixThreadPool}
     * @param metrics
     *            {@link HystrixThreadPoolMetrics} instance tracking metrics for the {@link HystrixThreadPool} instance having the key as defined by {@link HystrixThreadPoolKey}
     * @param properties
     *            {@link HystrixThreadPoolProperties} instance for the {@link HystrixThreadPool} instance having the key as defined by {@link HystrixThreadPoolKey}
     * @return instance of {@link HystrixMetricsPublisherThreadPool} that will have its <code>initialize</code> method invoked once.
     */
    public HystrixMetricsPublisherThreadPool getMetricsPublisherForThreadPool(HystrixThreadPoolKey threadPoolKey, HystrixThreadPoolMetrics metrics, HystrixThreadPoolProperties properties) {
        return new HystrixMetricsPublisherThreadPoolDefault(threadPoolKey, metrics, properties);
    }

    
Construct an implementation of HystrixMetricsPublisherCollapser for HystrixCollapser instances having key HystrixCollapserKey. 
 This will be invoked once per HystrixCollapserKey instance. 

Default Implementation

 Return instance of HystrixMetricsPublisherCollapserDefault 
Params:
Returns:instance of HystrixMetricsPublisherCollapser that will have its initialize method invoked once.
/**
     * Construct an implementation of {@link HystrixMetricsPublisherCollapser} for {@link HystrixCollapser} instances having key {@link HystrixCollapserKey}.
     * <p>
     * This will be invoked once per {@link HystrixCollapserKey} instance.
     * <p>
     * <b>Default Implementation</b>
     * <p>
     * Return instance of {@link HystrixMetricsPublisherCollapserDefault}
     *
     * @param collapserKey
     *            {@link HystrixCollapserKey} representing the name or type of {@link HystrixCollapser}
     * @param metrics
     *            {@link HystrixCollapserMetrics} instance tracking metrics for the {@link HystrixCollapser} instance having the key as defined by {@link HystrixCollapserKey}
     * @param properties
     *            {@link HystrixCollapserProperties} instance for the {@link HystrixCollapser} instance having the key as defined by {@link HystrixCollapserKey}
     * @return instance of {@link HystrixMetricsPublisherCollapser} that will have its <code>initialize</code> method invoked once.
     */
    public HystrixMetricsPublisherCollapser getMetricsPublisherForCollapser(HystrixCollapserKey collapserKey, HystrixCollapserMetrics metrics, HystrixCollapserProperties properties) {
        return new HystrixMetricsPublisherCollapserDefault(collapserKey, metrics, properties);
    }

}