https://github.com/Netflix/Hystrix: hystrix-core
  • Netflix Open Source Development 
Copyright 2013 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 2013 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.executionhook;

import com.netflix.hystrix.HystrixCommand;
import com.netflix.hystrix.HystrixCommandProperties.ExecutionIsolationStrategy;
import com.netflix.hystrix.HystrixInvokable;
import com.netflix.hystrix.HystrixObservableCommand;
import com.netflix.hystrix.exception.HystrixRuntimeException;
import com.netflix.hystrix.exception.HystrixRuntimeException.FailureType;
import com.netflix.hystrix.strategy.HystrixPlugins;


Abstract ExecutionHook with invocations at different lifecycle points of HystrixCommand and HystrixObservableCommand execution with default no-op implementations. 
 See HystrixPlugins or the Hystrix GitHub Wiki for information on configuring plugins: https://github.com/Netflix/Hystrix/wiki/Plugins.


Note on thread-safety and performance


A single implementation of this class will be used globally so methods on this class will be invoked concurrently from multiple threads so all functionality must be thread-safe.


Methods are also invoked synchronously and will add to execution time of the commands so all behavior should be fast. If anything time-consuming is to be done it should be spawned asynchronously
onto separate worker threads.

Since:1.2
/**
 * Abstract ExecutionHook with invocations at different lifecycle points of {@link HystrixCommand}
 * and {@link HystrixObservableCommand} execution with default no-op implementations.
 * <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>.
 * <p>
 * <b>Note on thread-safety and performance</b>
 * <p>
 * A single implementation of this class will be used globally so methods on this class will be invoked concurrently from multiple threads so all functionality must be thread-safe.
 * <p>
 * Methods are also invoked synchronously and will add to execution time of the commands so all behavior should be fast. If anything time-consuming is to be done it should be spawned asynchronously
 * onto separate worker threads.
 * 
 * @since 1.2
 * */
public abstract class HystrixCommandExecutionHook {

    
Invoked before HystrixInvokable begins executing. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.2
/**
     * Invoked before {@link HystrixInvokable} begins executing.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.2
     */
    public <T> void onStart(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked when HystrixInvokable emits a value. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • value – value emitted
Since:1.4
/**
     * Invoked when {@link HystrixInvokable} emits a value.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param value value emitted
     *
     * @since 1.4
     */
    public <T> T onEmit(HystrixInvokable<T> commandInstance, T value) {
        return value; //by default, just pass through
    }

    
Invoked when HystrixInvokable fails with an Exception. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • failureType – FailureType enum representing which type of error
  • e – exception object
Since:1.2
/**
     * Invoked when {@link HystrixInvokable} fails with an Exception.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param failureType {@link FailureType} enum representing which type of error
     * @param e exception object
     *
     * @since 1.2
     */
    public <T> Exception onError(HystrixInvokable<T> commandInstance, FailureType failureType, Exception e) {
        return e; //by default, just pass through
    }

    
Invoked when HystrixInvokable finishes a successful execution. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.4
/**
     * Invoked when {@link HystrixInvokable} finishes a successful execution.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.4
     */
    public <T> void onSuccess(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked at start of thread execution when HystrixCommand is executed using ExecutionIsolationStrategy.THREAD. 
Params:
  • commandInstance – The executing HystrixCommand instance.
Since:1.2
/**
     * Invoked at start of thread execution when {@link HystrixCommand} is executed using {@link ExecutionIsolationStrategy#THREAD}.
     *
     * @param commandInstance The executing HystrixCommand instance.
     *
     * @since 1.2
     */
    public <T> void onThreadStart(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked at completion of thread execution when HystrixCommand is executed using ExecutionIsolationStrategy.THREAD. This will get invoked whenever the Hystrix thread is done executing, regardless of whether the thread finished naturally, or was unsubscribed externally 
Params:
  • commandInstance – The executing HystrixCommand instance.
Since:1.2
/**
     * Invoked at completion of thread execution when {@link HystrixCommand} is executed using {@link ExecutionIsolationStrategy#THREAD}.
     * This will get invoked whenever the Hystrix thread is done executing, regardless of whether the thread finished
     * naturally, or was unsubscribed externally
     *
     * @param commandInstance The executing HystrixCommand instance.
     *
     * @since 1.2
     */
    public <T> void onThreadComplete(HystrixInvokable<T> commandInstance) {
        // do nothing by default
    }

    
Invoked when the user-defined execution method in HystrixInvokable starts. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.4
/**
     * Invoked when the user-defined execution method in {@link HystrixInvokable} starts.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.4
     */
    public <T> void onExecutionStart(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked when the user-defined execution method in HystrixInvokable emits a value. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • value – value emitted
Since:1.4
/**
     * Invoked when the user-defined execution method in {@link HystrixInvokable} emits a value.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param value value emitted
     *
     * @since 1.4
     */
    public <T> T onExecutionEmit(HystrixInvokable<T> commandInstance, T value) {
        return value; //by default, just pass through
    }

    
Invoked when the user-defined execution method in HystrixInvokable fails with an Exception. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • e – exception object
Since:1.4
/**
     * Invoked when the user-defined execution method in {@link HystrixInvokable} fails with an Exception.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param e exception object
     *
     * @since 1.4
     */
    public <T> Exception onExecutionError(HystrixInvokable<T> commandInstance, Exception e) {
        return e; //by default, just pass through
    }

    
Invoked when the user-defined execution method in HystrixInvokable completes successfully. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.4
/**
     * Invoked when the user-defined execution method in {@link HystrixInvokable} completes successfully.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.4
     */
    public <T> void onExecutionSuccess(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked when the fallback method in HystrixInvokable starts. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.2
/**
     * Invoked when the fallback method in {@link HystrixInvokable} starts.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.2
     */
    public <T> void onFallbackStart(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked when the fallback method in HystrixInvokable emits a value. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • value – value emitted
Since:1.4
/**
     * Invoked when the fallback method in {@link HystrixInvokable} emits a value.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param value value emitted
     *
     * @since 1.4
     */
    public <T> T onFallbackEmit(HystrixInvokable<T> commandInstance, T value) {
        return value; //by default, just pass through
    }

    
Invoked when the fallback method in HystrixInvokable fails with an Exception. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
  • e – exception object
Since:1.2
/**
     * Invoked when the fallback method in {@link HystrixInvokable} fails with an Exception.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     * @param e exception object
     *
     * @since 1.2
     */
    public <T> Exception onFallbackError(HystrixInvokable<T> commandInstance, Exception e) {
        //by default, just pass through
        return e;
    }

    
Invoked when the user-defined execution method in HystrixInvokable completes successfully. 
Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.4
/**
     * Invoked when the user-defined execution method in {@link HystrixInvokable} completes successfully.
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.4
     */
    public <T> void onFallbackSuccess(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked when the command response is found in the HystrixRequestCache. 
Params:
  • commandInstance – The executing HystrixCommand
Since:1.4
/**
     * Invoked when the command response is found in the {@link com.netflix.hystrix.HystrixRequestCache}.
     *
     * @param commandInstance The executing HystrixCommand
     *
     * @since 1.4
     */
    public <T> void onCacheHit(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
Invoked with the command is unsubscribed before a terminal state

Params:
  • commandInstance – The executing HystrixInvokable instance.
Since:1.5.9
/**
     * Invoked with the command is unsubscribed before a terminal state
     *
     * @param commandInstance The executing HystrixInvokable instance.
     *
     * @since 1.5.9
     */
    public <T> void onUnsubscribe(HystrixInvokable<T> commandInstance) {
        //do nothing by default
    }

    
DEPRECATED: Change usages of this to onExecutionStart. Invoked before HystrixCommand.run() is about to be executed. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionStart}.
     *
     * Invoked before {@link HystrixCommand#run()} is about to be executed.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> void onRunStart(HystrixCommand<T> commandInstance) {
        // do nothing by default
    }

    
DEPRECATED: Change usages of this to onExecutionStart. Invoked before HystrixCommand.run() is about to be executed. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionStart}.
     *
     * Invoked before {@link HystrixCommand#run()} is about to be executed.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     *
     * @since 1.2
     */
    @Deprecated
    public <T> void onRunStart(HystrixInvokable<T> commandInstance) {
        // do nothing by default
    }

    
DEPRECATED: Change usages of this to onExecutionEmit if you want to add a hook for each value emitted by the command or to onExecutionSuccess if you want to add a hook when the command successfully executes Invoked after successful execution of HystrixCommand.run() with response value. In a HystrixCommand using ExecutionIsolationStrategy.THREAD, this will get invoked if the Hystrix thread successfully runs, regardless of whether the calling thread encountered a timeout. 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionEmit} if you want to add a hook for each value emitted by the command
     * or to {@link #onExecutionSuccess} if you want to add a hook when the command successfully executes
     *
     * Invoked after successful execution of {@link HystrixCommand#run()} with response value.
     * In a {@link HystrixCommand} using {@link ExecutionIsolationStrategy#THREAD}, this will get invoked if the Hystrix thread
     * successfully runs, regardless of whether the calling thread encountered a timeout.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param response
     *            from {@link HystrixCommand#run()}
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> T onRunSuccess(HystrixCommand<T> commandInstance, T response) {
        // pass-thru by default
        return response;
    }

    
DEPRECATED: Change usages of this to onExecutionEmit if you want to add a hook for each value emitted by the command or to onExecutionSuccess if you want to add a hook when the command successfully executes Invoked after successful execution of HystrixCommand.run() with response value. In a HystrixCommand using ExecutionIsolationStrategy.THREAD, this will get invoked if the Hystrix thread successfully runs, regardless of whether the calling thread encountered a timeout. 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionEmit} if you want to add a hook for each value emitted by the command
     * or to {@link #onExecutionSuccess} if you want to add a hook when the command successfully executes
     *
     * Invoked after successful execution of {@link HystrixCommand#run()} with response value.
     * In a {@link HystrixCommand} using {@link ExecutionIsolationStrategy#THREAD}, this will get invoked if the Hystrix thread
     * successfully runs, regardless of whether the calling thread encountered a timeout.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param response
     *            from {@link HystrixCommand#run()}
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     *
     * @since 1.2
     */
    @Deprecated
    public <T> T onRunSuccess(HystrixInvokable<T> commandInstance, T response) {
        // pass-thru by default
        return response;
    }

    
DEPRECATED: Change usages of this to onExecutionError Invoked after failed execution of HystrixCommand.run() with thrown Exception. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
  • e –  Exception thrown by HystrixCommand.run()
Returns:Exception that can be decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionError}
     *
     * Invoked after failed execution of {@link HystrixCommand#run()} with thrown Exception.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param e
     *            Exception thrown by {@link HystrixCommand#run()}
     * @return Exception that can be decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> Exception onRunError(HystrixCommand<T> commandInstance, Exception e) {
        // pass-thru by default
        return e;
    }

    
DEPRECATED: Change usages of this to onExecutionError Invoked after failed execution of HystrixCommand.run() with thrown Exception. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
  • e –  Exception thrown by HystrixCommand.run()
Returns:Exception that can be decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onExecutionError}
     *
     * Invoked after failed execution of {@link HystrixCommand#run()} with thrown Exception.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param e
     *            Exception thrown by {@link HystrixCommand#run()}
     * @return Exception that can be decorated, replaced or just returned as a pass-thru.
     *
     * @since 1.2
     */
    @Deprecated
    public <T> Exception onRunError(HystrixInvokable<T> commandInstance, Exception e) {
        // pass-thru by default
        return e;
    }

    
DEPRECATED: Change usages of this to onFallbackStart Invoked before HystrixCommand.getFallback() is about to be executed. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onFallbackStart}
     *
     * Invoked before {@link HystrixCommand#getFallback()} is about to be executed.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> void onFallbackStart(HystrixCommand<T> commandInstance) {
        // do nothing by default
    }

    
DEPRECATED: Change usages of this to onFallbackEmit if you want to write a hook that handles each emitted fallback value or to onFallbackSuccess if you want to write a hook that handles success of the fallback method Invoked after successful execution of HystrixCommand.getFallback() with response value. 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onFallbackEmit} if you want to write a hook that handles each emitted fallback value
     * or to {@link #onFallbackSuccess} if you want to write a hook that handles success of the fallback method
     *
     * Invoked after successful execution of {@link HystrixCommand#getFallback()} with response value.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param fallbackResponse
     *            from {@link HystrixCommand#getFallback()}
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> T onFallbackSuccess(HystrixCommand<T> commandInstance, T fallbackResponse) {
        // pass-thru by default
        return fallbackResponse;
    }

    
DEPRECATED: Change usages of this to onFallbackEmit if you want to write a hook that handles each emitted fallback value or to onFallbackSuccess if you want to write a hook that handles success of the fallback method Invoked after successful execution of HystrixCommand.getFallback() with response value. 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onFallbackEmit} if you want to write a hook that handles each emitted fallback value
     * or to {@link #onFallbackSuccess} if you want to write a hook that handles success of the fallback method
     *
     * Invoked after successful execution of {@link HystrixCommand#getFallback()} with response value.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param fallbackResponse
     *            from {@link HystrixCommand#getFallback()}
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     *
     * @since 1.2
     */
    @Deprecated
    public <T> T onFallbackSuccess(HystrixInvokable<T> commandInstance, T fallbackResponse) {
        // pass-thru by default
        return fallbackResponse;
    }

    
DEPRECATED: Change usages of this to onFallbackError. Invoked after failed execution of HystrixCommand.getFallback() with thrown exception. 
Params:
Returns:Exception that can be decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onFallbackError}.
     *
     * Invoked after failed execution of {@link HystrixCommand#getFallback()} with thrown exception.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param e
     *            Exception thrown by {@link HystrixCommand#getFallback()}
     * @return Exception that can be decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> Exception onFallbackError(HystrixCommand<T> commandInstance, Exception e) {
        // pass-thru by default
        return e;
    }

    
DEPRECATED: Change usages of this to onStart. Invoked before HystrixCommand executes. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onStart}.
     *
     * Invoked before {@link HystrixCommand} executes.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> void onStart(HystrixCommand<T> commandInstance) {
        // do nothing by default
    }

    
DEPRECATED: Change usages of this to onEmit if you want to write a hook that handles each emitted command value or to onSuccess if you want to write a hook that handles success of the command Invoked after completion of HystrixCommand execution that results in a response. 
 The response can come either from HystrixCommand.run() or HystrixCommand.getFallback(). 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onEmit} if you want to write a hook that handles each emitted command value
     * or to {@link #onSuccess} if you want to write a hook that handles success of the command
     *
     * Invoked after completion of {@link HystrixCommand} execution that results in a response.
     * <p>
     * The response can come either from {@link HystrixCommand#run()} or {@link HystrixCommand#getFallback()}.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param response
     *            from {@link HystrixCommand#run()} or {@link HystrixCommand#getFallback()}.
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> T onComplete(HystrixCommand<T> commandInstance, T response) {
        // pass-thru by default
        return response;
    }

    
DEPRECATED: Change usages of this to onEmit if you want to write a hook that handles each emitted command value or to onSuccess if you want to write a hook that handles success of the command Invoked after completion of HystrixCommand execution that results in a response. 
 The response can come either from HystrixCommand.run() or HystrixCommand.getFallback(). 
Params:
Returns:T response object that can be modified, decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onEmit} if you want to write a hook that handles each emitted command value
     * or to {@link #onSuccess} if you want to write a hook that handles success of the command
     *
     * Invoked after completion of {@link HystrixCommand} execution that results in a response.
     * <p>
     * The response can come either from {@link HystrixCommand#run()} or {@link HystrixCommand#getFallback()}.
     *
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param response
     *            from {@link HystrixCommand#run()} or {@link HystrixCommand#getFallback()}.
     * @return T response object that can be modified, decorated, replaced or just returned as a pass-thru.
     *
     * @since 1.2
     */
    @Deprecated
    public <T> T onComplete(HystrixInvokable<T> commandInstance, T response) {
        // pass-thru by default
        return response;
    }

    
DEPRECATED: Change usages of this to onError. Invoked after failed completion of HystrixCommand execution. 
Params:
Returns:Exception that can be decorated, replaced or just returned as a pass-thru.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onError}.
     *
     * Invoked after failed completion of {@link HystrixCommand} execution.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * @param failureType
     *            {@link FailureType} representing the type of failure that occurred.
     *            <p>
     *            See {@link HystrixRuntimeException} for more information.
     * @param e
     *            Exception thrown by {@link HystrixCommand}
     * @return Exception that can be decorated, replaced or just returned as a pass-thru.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> Exception onError(HystrixCommand<T> commandInstance, FailureType failureType, Exception e) {
        // pass-thru by default
        return e;
    }

    
DEPRECATED: Change usages of this to onThreadStart. Invoked at start of thread execution when HystrixCommand is executed using ExecutionIsolationStrategy.THREAD. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onThreadStart}.
     *
     * Invoked at start of thread execution when {@link HystrixCommand} is executed using {@link ExecutionIsolationStrategy#THREAD}.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> void onThreadStart(HystrixCommand<T> commandInstance) {
        // do nothing by default
    }

    
DEPRECATED: Change usages of this to onThreadComplete. Invoked at completion of thread execution when HystrixCommand is executed using ExecutionIsolationStrategy.THREAD. This will get invoked if the Hystrix thread successfully executes, regardless of whether the calling thread encountered a timeout. 
Params:
  • commandInstance – 
           The executing HystrixCommand instance.
Since:1.2
/**
     * DEPRECATED: Change usages of this to {@link #onThreadComplete}.
     *
     * Invoked at completion of thread execution when {@link HystrixCommand} is executed using {@link ExecutionIsolationStrategy#THREAD}.
     * This will get invoked if the Hystrix thread successfully executes, regardless of whether the calling thread
     * encountered a timeout.
     * 
     * @param commandInstance
     *            The executing HystrixCommand instance.
     * 
     * @since 1.2
     */
    @Deprecated
    public <T> void onThreadComplete(HystrixCommand<T> commandInstance) {
        // do nothing by default
    }
}