CallableQueueService (Apache Oozie Core 4.3.1 API)

java.lang.Object
- org.apache.oozie.service.CallableQueueService

All Implemented Interfaces:

Service, Instrumentable
```
public class CallableQueueService
extends Object
implements Service, Instrumentable
```
The callable queue service queues XCallables for asynchronous execution.
Callables can be queued for immediate execution or for delayed execution (some time in the future).
Callables are consumed from the queue for execution based on their priority.
When the queues (for immediate execution and for delayed execution) are full, the callable queue service stops queuing callables.
A thread-pool is used to execute the callables asynchronously.
The following configuration parameters control the callable queue service:
CONF_QUEUE_SIZE size of the immediate execution queue. Defaulf value is 10000.
CONF_THREADS number of threads in the thread-pool used for asynchronous command execution. When this number of threads is reached, commands remain the queue until threads become available. Sets up a priority queue for the execution of Commands via a ThreadPool. Sets up a Delayed Queue to handle actions which will be ready for execution sometime in the future.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

class CallableQueueService.CallableWrapper<E>

Nested Classes
Modifier and Type	Class and Description
`class`	`CallableQueueService.CallableWrapper<E>`

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`CONCURRENCY_DELAY`
`static String`	`CONF_CALLABLE_CONCURRENCY`
`static String`	`CONF_CALLABLE_INTERRUPT_MAP_MAX_SIZE`
`static String`	`CONF_CALLABLE_INTERRUPT_TYPES`
`static String`	`CONF_CALLABLE_NEXT_ELIGIBLE`
`static String`	`CONF_PREFIX`
`static String`	`CONF_QUEUE_SIZE`
`static String`	`CONF_THREADS`
`static HashSet<String>`	`INTERRUPT_TYPES`
`static int`	`SAFE_MODE_DELAY`

Fields inherited from interface org.apache.oozie.service.Service
DEFAULT_LOCK_TIMEOUT, lockTimeout

Constructor Summary

Constructors
Constructor and Description

CallableQueueService()

Constructors
Constructor and Description
`CallableQueueService()`

Method Summary

Methods
Modifier and Type	Method and Description
`Set<XCallable<?>>`	`checkInterrupts(String lockKey)` check the interrupt map for the existence of an interrupt commands if exist a List of Interrupt Callable for the same lock key will bereturned, otherwise it will return null
`void`	`checkInterruptTypes(XCallable<?> callable)` check if the callable is of an interrupt type and insert it into the map accordingly
`void`	`destroy()` Destroy the command queue service.
`Class<? extends Service>`	`getInterface()` Return the public interface for command queue service.
`List<String>`	`getQueueDump()` Get the list of strings of queue dump
`List<String>`	`getUniqueDump()` Get the list of strings of uniqueness map dump
`void`	`init(Services services)` Initialize the command queue service.
`void`	`insertCallableIntoInterruptMap(XCallable<?> callable)` insert a new callable in the Interrupt Command Map add a new element to the list or create a new list accordingly
`void`	`instrument(Instrumentation instr)` Instruments the callable queue service.
`<T> List<Future<T>>`	`invokeAll(List<CallableQueueService.CallableWrapper<T>> tasks)`
`boolean`	`queue(XCallable<?> callable)` Queue a callable for asynchronous execution.
`boolean`	`queue(XCallable<?> callable, long delay)` Queue a callable for asynchronous execution sometime in the future.
`boolean`	`queueSerial(List<? extends XCallable<?>> callables)` Queue a list of callables for serial execution.
`boolean`	`queueSerial(List<? extends XCallable<?>> callables, long delay)` Queue a list of callables for serial execution sometime in the future.
`int`	`queueSize()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CONF_PREFIX
```
public static final String CONF_PREFIX
```
    See Also:
    Constant Field Values
  - CONF_QUEUE_SIZE
```
public static final String CONF_QUEUE_SIZE
```
    See Also:
    Constant Field Values
  - CONF_THREADS
```
public static final String CONF_THREADS
```
    See Also:
    Constant Field Values
  - CONF_CALLABLE_CONCURRENCY
```
public static final String CONF_CALLABLE_CONCURRENCY
```
    See Also:
    Constant Field Values
  - CONF_CALLABLE_NEXT_ELIGIBLE
```
public static final String CONF_CALLABLE_NEXT_ELIGIBLE
```
    See Also:
    Constant Field Values
  - CONF_CALLABLE_INTERRUPT_TYPES
```
public static final String CONF_CALLABLE_INTERRUPT_TYPES
```
    See Also:
    Constant Field Values
  - CONF_CALLABLE_INTERRUPT_MAP_MAX_SIZE
```
public static final String CONF_CALLABLE_INTERRUPT_MAP_MAX_SIZE
```
    See Also:
    Constant Field Values
  - CONCURRENCY_DELAY
```
public static final int CONCURRENCY_DELAY
```
    See Also:
    Constant Field Values
  - SAFE_MODE_DELAY
```
public static final int SAFE_MODE_DELAY
```
    See Also:
    Constant Field Values
  - INTERRUPT_TYPES
```
public static final HashSet<String> INTERRUPT_TYPES
```
- Constructor Detail
  - CallableQueueService
```
public CallableQueueService()
```
- Method Detail
  - init
```
public void init(Services services)
```
    Initialize the command queue service.
    
    Specified by:
    
    init in interface Service
    
    Parameters:
    services - services instance.
  - destroy
```
public void destroy()
```
    Destroy the command queue service.
    
    Specified by:
    
    destroy in interface Service
  - getInterface
```
public Class<? extends Service> getInterface()
```
    Return the public interface for command queue service.
    
    Specified by:
    
    getInterface in interface Service
    
    Returns:
    CallableQueueService.
  - queueSize
```
public int queueSize()
```
    Returns:
    int size of queue
  - queue
```
public boolean queue(XCallable<?> callable)
```
    Queue a callable for asynchronous execution.
    
    Parameters:
    callable - callable to queue.
    
    Returns:
    true if the callable was queued, false if the queue is full and the callable was not queued.
  - queueSerial
```
public boolean queueSerial(List<? extends XCallable<?>> callables)
```
    Queue a list of callables for serial execution.
    Useful to serialize callables that may compete with each other for resources.
    All callables will be processed with the priority of the highest priority of all callables.
    
    Parameters:
    callables - callables to be executed by the composite callable.
    
    Returns:
    true if the callables were queued, false if the queue is full and the callables were not queued.
  - queue
```
public boolean queue(XCallable<?> callable,
            long delay)
```
    Queue a callable for asynchronous execution sometime in the future.
    
    Parameters:
    callable - callable to queue for delayed execution
    delay - time, in milliseconds, that the callable should be delayed.
    
    Returns:
    true if the callable was queued, false if the queue is full and the callable was not queued.
  - queueSerial
```
public boolean queueSerial(List<? extends XCallable<?>> callables,
                  long delay)
```
    Queue a list of callables for serial execution sometime in the future.
    Useful to serialize callables that may compete with each other for resources.
    All callables will be processed with the priority of the highest priority of all callables.
    
    Parameters:
    callables - callables to be executed by the composite callable.
    delay - time, in milliseconds, that the callable should be delayed.
    
    Returns:
    true if the callables were queued, false if the queue is full and the callables were not queued.
  - instrument
```
public void instrument(Instrumentation instr)
```
    Instruments the callable queue service.
    
    Specified by:
    
    instrument in interface Instrumentable
    
    Parameters:
    instr - instance to instrument the callable queue service to.
  - checkInterrupts
```
public Set<XCallable<?>> checkInterrupts(String lockKey)
```
    check the interrupt map for the existence of an interrupt commands if exist a List of Interrupt Callable for the same lock key will bereturned, otherwise it will return null
  - checkInterruptTypes
```
public void checkInterruptTypes(XCallable<?> callable)
```
    check if the callable is of an interrupt type and insert it into the map accordingly
    
    Parameters:
    callable -
  - insertCallableIntoInterruptMap
```
public void insertCallableIntoInterruptMap(XCallable<?> callable)
```
    insert a new callable in the Interrupt Command Map add a new element to the list or create a new list accordingly
    
    Parameters:
    callable -
  - getQueueDump
```
public List<String> getQueueDump()
```
    Get the list of strings of queue dump
    
    Returns:
    the list of string that representing each CallableWrapper
  - getUniqueDump
```
public List<String> getUniqueDump()
```
    Get the list of strings of uniqueness map dump
    
    Returns:
    the list of string that representing the key of each command in the queue
  - invokeAll
```
public <T> List<Future<T>> invokeAll(List<CallableQueueService.CallableWrapper<T>> tasks)
                          throws InterruptedException
```
    Throws:
    
    InterruptedException

Class CallableQueueService

Nested Class Summary

Field Summary

Fields inherited from interface org.apache.oozie.service.Service

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CONF_PREFIX

CONF_QUEUE_SIZE

CONF_THREADS

CONF_CALLABLE_CONCURRENCY

CONF_CALLABLE_NEXT_ELIGIBLE

CONF_CALLABLE_INTERRUPT_TYPES

CONF_CALLABLE_INTERRUPT_MAP_MAX_SIZE

CONCURRENCY_DELAY

SAFE_MODE_DELAY

INTERRUPT_TYPES

Constructor Detail

CallableQueueService

Method Detail

init

destroy

getInterface

queueSize

queue

queueSerial

queue

queueSerial

instrument

checkInterrupts

checkInterruptTypes

insertCallableIntoInterruptMap

getQueueDump

getUniqueDump

invokeAll