EPStatementImpl (Esper Runtime API Documentation)

java.lang.Object
- com.espertech.esper.runtime.internal.kernel.statement.EPStatementImpl

All Implemented Interfaces:

EPIterable, EPListenable, EPStatement, EPStatementSPI
```
public class EPStatementImpl
extends Object
implements EPStatementSPI
```

Field Summary

Fields
Modifier and Type	Field and Description
`protected boolean`	`destroyed`
`protected com.espertech.esper.common.internal.statement.dispatch.UpdateDispatchView`	`dispatchChildView`
`protected com.espertech.esper.common.internal.view.core.Viewable`	`parentView`
`protected com.espertech.esper.common.internal.context.util.StatementContext`	`statementContext`
`protected StatementResultServiceImpl`	`statementResultService`

Constructor Summary

Constructors
Constructor and Description

EPStatementImpl(EPStatementFactoryArgs args)

Constructors
Constructor and Description
`EPStatementImpl(EPStatementFactoryArgs args)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addListener(UpdateListener listener)` Add a listener that observes events.
`void`	`addListenerWithReplay(UpdateListener listener)` Add an update listener replaying current statement results to the listener.
`protected void`	`checkDestroyed()`
`Annotation[]`	`getAnnotations()` Returns statement annotations.
`String`	`getDeploymentId()` Returns the deployment id.
`com.espertech.esper.common.internal.statement.dispatch.UpdateDispatchView`	`getDispatchChildView()`
`com.espertech.esper.common.client.EventType`	`getEventType()` Returns the type of events the statement pushes to listeners or returns for iterator.
`String`	`getName()` Returns the statement name.
`com.espertech.esper.common.internal.view.core.Viewable`	`getParentView()` Returns the parent view.
`Object`	`getProperty(com.espertech.esper.common.client.util.StatementProperty field)` Returns a statement property value.
`com.espertech.esper.common.internal.context.util.StatementContext`	`getStatementContext()` Returns the statement context.
`int`	`getStatementId()` Returns the statement id.
`Object`	`getSubscriber()` Returns the current subscriber instance that receives statement results.
`Iterator<UpdateListener>`	`getUpdateListeners()` Returns an iterator of update listeners.
`Object`	`getUserObjectCompileTime()` Returns the application defined user data object associated with the statement at compile time, or null if none was supplied at time of statement compilation.
`Object`	`getUserObjectRuntime()` Returns the application defined user data object associated with the statement at deployment time, or null if none was supplied at time of deployment.
`boolean`	`isDestroyed()` Returns true if the statement has been undeployed.
`Iterator<com.espertech.esper.common.client.EventBean>`	`iterator()` Returns a concurrency-unsafe iterator over events representing statement results (pull API).
`Iterator<com.espertech.esper.common.client.EventBean>`	`iterator(com.espertech.esper.common.client.context.ContextPartitionSelector selector)` For use with statements that have a context declared and that may therefore have multiple context partitions, allows to iterate over context partitions selectively.
`void`	`recoveryUpdateListeners(EPStatementListenerSet listenerSet)`
`void`	`removeAllListeners()` Remove all listeners.
`void`	`removeListener(UpdateListener listener)` Remove a listener that observes events.
`com.espertech.esper.common.client.util.SafeIterator<com.espertech.esper.common.client.EventBean>`	`safeIterator()` Returns a concurrency-safe iterator that iterates over events representing statement results (pull API) in the face of concurrent event processing by further threads.
`com.espertech.esper.common.client.util.SafeIterator<com.espertech.esper.common.client.EventBean>`	`safeIterator(com.espertech.esper.common.client.context.ContextPartitionSelector selector)` For use with statements that have a context declared and that may therefore have multiple context partitions, allows to safe-iterate over context partitions selectively.
`void`	`setDestroyed()`
`void`	`setParentView(com.espertech.esper.common.internal.view.core.Viewable viewable)` Sets the parent view.
`void`	`setSubscriber(Object subscriber)` Attaches a subscriber to receive statement results, or removes a previously set subscriber (by providing a null value).
`void`	`setSubscriber(Object subscriber, String methodName)` Attaches a subscriber to receive statement results by calling the method with the provided method name, or removes a previously set subscriber (by providing a null value).

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

- Field Detail
  - statementContext
```
protected final com.espertech.esper.common.internal.context.util.StatementContext statementContext
```
  - dispatchChildView
```
protected final com.espertech.esper.common.internal.statement.dispatch.UpdateDispatchView dispatchChildView
```
  - statementResultService
```
protected final StatementResultServiceImpl statementResultService
```
  - parentView
```
protected com.espertech.esper.common.internal.view.core.Viewable parentView
```
  - destroyed
```
protected boolean destroyed
```
- Constructor Detail
  - EPStatementImpl
```
public EPStatementImpl(EPStatementFactoryArgs args)
```
- Method Detail
  - addListener
```
public void addListener(UpdateListener listener)
```
    Description copied from interface: EPListenable
    
    Add a listener that observes events.
    
    Specified by:
    
    addListener in interface EPListenable
    
    Parameters:
    
    listener - to add
  - getStatementId
```
public int getStatementId()
```
    Description copied from interface: EPStatementSPI
    
    Returns the statement id.
    
    Specified by:
    
    getStatementId in interface EPStatementSPI
    
    Returns:
    
    statement id
  - getStatementContext
```
public com.espertech.esper.common.internal.context.util.StatementContext getStatementContext()
```
    Description copied from interface: EPStatementSPI
    
    Returns the statement context.
    
    Specified by:
    
    getStatementContext in interface EPStatementSPI
    
    Returns:
    
    statement context
  - getName
```
public String getName()
```
    Description copied from interface: EPStatement
    
    Returns the statement name.
    
    Specified by:
    
    getName in interface EPStatement
    
    Returns:
    
    statement name
  - getDispatchChildView
```
public com.espertech.esper.common.internal.statement.dispatch.UpdateDispatchView getDispatchChildView()
```
    Specified by:
    
    getDispatchChildView in interface EPStatementSPI
  - isDestroyed
```
public boolean isDestroyed()
```
    Description copied from interface: EPStatement
    
    Returns true if the statement has been undeployed.
    
    Specified by:
    
    isDestroyed in interface EPStatement
    
    Returns:
    
    true for undeployed statements, false for deployed statements.
  - recoveryUpdateListeners
```
public void recoveryUpdateListeners(EPStatementListenerSet listenerSet)
```
    Specified by:
    
    recoveryUpdateListeners in interface EPStatementSPI
  - getEventType
```
public com.espertech.esper.common.client.EventType getEventType()
```
    Description copied from interface: EPStatement
    
    Returns the type of events the statement pushes to listeners or returns for iterator.
    
    Specified by:
    
    getEventType in interface EPStatement
    
    Returns:
    
    event type of events the iterator returns and that listeners receive
  - getAnnotations
```
public Annotation[] getAnnotations()
```
    Description copied from interface: EPStatement
    
    Returns statement annotations.
    See the annotation com.espertech.esper.common.client.annotation package for available annotations. Application can define their own annotations.
    
    Specified by:
    
    getAnnotations in interface EPStatement
    
    Returns:
    
    annotations or a zero-length array if no annotaions have been specified.
  - iterator
```
public Iterator<com.espertech.esper.common.client.EventBean> iterator()
```
    Description copied from interface: EPIterable
    
    Returns a concurrency-unsafe iterator over events representing statement results (pull API).
    The iterator is useful for applications that are single-threaded, or that coordinate the iterating thread with event processing threads that use the sendEvent method using application code locks or synchronization.
    The iterator returned by this method does not make any guarantees towards correctness of results and fail-behavior, if your application processes events into the runtime instance using the sendEvent method by multiple threads.
    Use the safeIterator method for concurrency-safe iteration. Note the safe iterator requires applications to explicitly close the safe iterator when done iterating.
    
    Specified by:
    
    iterator in interface EPIterable
    
    Returns:
    
    event iterator
  - safeIterator
```
public com.espertech.esper.common.client.util.SafeIterator<com.espertech.esper.common.client.EventBean> safeIterator()
```
    Description copied from interface: EPIterable
    
    Returns a concurrency-safe iterator that iterates over events representing statement results (pull API) in the face of concurrent event processing by further threads.
    In comparison to the regular iterator, the safe iterator guarantees correct results even as events are being processed by other threads. The cost is that the iterator holds one or more locks that must be released via the close method. Any locks are acquired at the time this method is called.
    This method is a blocking method. It may block until statement processing locks are released such that the safe iterator can acquire any required locks.
    An application MUST explicitly close the safe iterator instance using the close method, to release locks held by the iterator. The call to the close method should be done in a finally block to make sure the iterator gets closed.
    Multiple safe iterators may be not be used at the same time by different application threads. A single application thread may hold and use multiple safe iterators however this is discouraged.
    
    Specified by:
    
    safeIterator in interface EPIterable
    
    Returns:
    
    safe iterator; NOTE: Must use the close method to close the safe iterator, preferably in a finally block
  - removeListener
```
public void removeListener(UpdateListener listener)
```
    Description copied from interface: EPListenable
    
    Remove a listener that observes events.
    
    Specified by:
    
    removeListener in interface EPListenable
    
    Parameters:
    
    listener - to remove
  - removeAllListeners
```
public void removeAllListeners()
```
    Description copied from interface: EPListenable
    
    Remove all listeners.
    
    Specified by:
    
    removeAllListeners in interface EPListenable
  - getUpdateListeners
```
public Iterator<UpdateListener> getUpdateListeners()
```
    Description copied from interface: EPListenable
    
    Returns an iterator of update listeners.
    The returned iterator does not allow the remove operation.
    
    Specified by:
    
    getUpdateListeners in interface EPListenable
    
    Returns:
    
    iterator of update listeners
  - getParentView
```
public com.espertech.esper.common.internal.view.core.Viewable getParentView()
```
    Description copied from interface: EPStatementSPI
    
    Returns the parent view.
    
    Specified by:
    
    getParentView in interface EPStatementSPI
    
    Returns:
    
    viewable is the statement parent viewable
  - setParentView
```
public void setParentView(com.espertech.esper.common.internal.view.core.Viewable viewable)
```
    Description copied from interface: EPStatementSPI
    
    Sets the parent view.
    
    Specified by:
    
    setParentView in interface EPStatementSPI
    
    Parameters:
    
    viewable - is the statement viewable
  - setDestroyed
```
public void setDestroyed()
```
    Specified by:
    
    setDestroyed in interface EPStatementSPI
  - iterator
```
public Iterator<com.espertech.esper.common.client.EventBean> iterator(com.espertech.esper.common.client.context.ContextPartitionSelector selector)
```
    Description copied from interface: EPIterable
    
    For use with statements that have a context declared and that may therefore have multiple context partitions, allows to iterate over context partitions selectively.
    
    Specified by:
    
    iterator in interface EPIterable
    
    Parameters:
    
    selector - selects context partitions to consider
    
    Returns:
    
    iterator
  - safeIterator
```
public com.espertech.esper.common.client.util.SafeIterator<com.espertech.esper.common.client.EventBean> safeIterator(com.espertech.esper.common.client.context.ContextPartitionSelector selector)
```
    Description copied from interface: EPIterable
    
    For use with statements that have a context declared and that may therefore have multiple context partitions, allows to safe-iterate over context partitions selectively.
    
    Specified by:
    
    safeIterator in interface EPIterable
    
    Parameters:
    
    selector - selects context partitions to consider
    
    Returns:
    
    safe iterator
  - getDeploymentId
```
public String getDeploymentId()
```
    Description copied from interface: EPStatement
    
    Returns the deployment id.
    
    Specified by:
    
    getDeploymentId in interface EPStatement
    
    Returns:
    
    deployment id
  - setSubscriber
```
public void setSubscriber(Object subscriber)
```
    Description copied from interface: EPStatement
    
    Attaches a subscriber to receive statement results, or removes a previously set subscriber (by providing a null value).
    Note: Requires the allow-subscriber compiler options.
    Only a single subscriber may be set for a statement. If this method is invoked twice any previously-set subscriber is no longer used.
    
    Specified by:
    
    setSubscriber in interface EPStatement
    
    Parameters:
    
    subscriber - to attach, or null to remove the previously set subscriber
  - setSubscriber
```
public void setSubscriber(Object subscriber,
                          String methodName)
```
    Description copied from interface: EPStatement
    
    Attaches a subscriber to receive statement results by calling the method with the provided method name, or removes a previously set subscriber (by providing a null value).
    Note: Requires the allow-subscriber compiler options.
    Only a single subscriber may be set for a statement. If this method is invoked twice any previously-set subscriber is no longer used.
    
    Specified by:
    
    setSubscriber in interface EPStatement
    
    Parameters:
    
    subscriber - to attach, or null to remove the previously set subscriber
    
    methodName - the name of the method to invoke, or null for the "update" method
  - getSubscriber
```
public Object getSubscriber()
```
    Description copied from interface: EPStatement
    
    Returns the current subscriber instance that receives statement results.
    
    Specified by:
    
    getSubscriber in interface EPStatement
    
    Returns:
    
    subscriber object, or null to indicate that no subscriber is attached
  - getProperty
```
public Object getProperty(com.espertech.esper.common.client.util.StatementProperty field)
```
    Description copied from interface: EPStatement
    
    Returns a statement property value.
    
    Specified by:
    
    getProperty in interface EPStatement
    
    Parameters:
    
    field - statement property value
    
    Returns:
    
    property or null if not set
  - addListenerWithReplay
```
public void addListenerWithReplay(UpdateListener listener)
```
    Description copied from interface: EPListenable
    
    Add an update listener replaying current statement results to the listener.
    The listener receives current statement results as the first call to the update method of the listener, passing in the newEvents parameter the current statement results as an array of zero or more events. Subsequent calls to the update method of the listener are statement results.
    Current statement results are the events returned by the iterator or safeIterator methods.
    Delivery of current statement results in the first call is performed by the same thread invoking this method, while subsequent calls to the listener may deliver statement results by the same or other threads.
    Note: this is a blocking call, delivery is atomic: Events occurring during iteration and delivery to the listener are guaranteed to be delivered in a separate call and not lost. The listener implementation should minimize long-running or blocking operations.
    Delivery is only atomic relative to the current statement. If the same listener instance is registered with other statements it may receive other statement result s simultaneously.
    If a statement is not started an therefore does not have current results, the listener receives a single invocation with a null value in newEvents.
    
    Specified by:
    
    addListenerWithReplay in interface EPListenable
    
    Parameters:
    
    listener - to add
  - getUserObjectCompileTime
```
public Object getUserObjectCompileTime()
```
    Description copied from interface: EPStatement
    
    Returns the application defined user data object associated with the statement at compile time, or null if none was supplied at time of statement compilation.
    The user object is a single, unnamed field that is stored with every statement. Applications may put arbitrary objects in this field or a null value.
    User objects are passed at time of statement compilation via options.
    
    Specified by:
    
    getUserObjectCompileTime in interface EPStatement
    
    Returns:
    
    user object or null if none defined
  - getUserObjectRuntime
```
public Object getUserObjectRuntime()
```
    Description copied from interface: EPStatement
    
    Returns the application defined user data object associated with the statement at deployment time, or null if none was supplied at time of deployment.
    The user object is a single, unnamed field that is stored with every statement. Applications may put arbitrary objects in this field or a null value.
    User objects are passed at time of deployment via options.
    
    Specified by:
    
    getUserObjectRuntime in interface EPStatement
    
    Returns:
    
    user object or null if none defined
  - checkDestroyed
```
protected void checkDestroyed()
```

Class EPStatementImpl

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

statementContext

dispatchChildView

statementResultService

parentView

destroyed

Constructor Detail

EPStatementImpl

Method Detail

addListener

getStatementId

getStatementContext

getName

getDispatchChildView

isDestroyed

recoveryUpdateListeners

getEventType

getAnnotations

iterator

safeIterator

removeListener

removeAllListeners

getUpdateListeners

getParentView

setParentView

setDestroyed

iterator

safeIterator

getDeploymentId

setSubscriber

setSubscriber

getSubscriber

getProperty

addListenerWithReplay

getUserObjectCompileTime

getUserObjectRuntime

checkDestroyed