org.wso2.siddhi.core.event.stream.holder

Class SnapshotableStreamEventQueue

java.lang.Object

org.wso2.siddhi.core.event.stream.holder.SnapshotableStreamEventQueue

All Implemented Interfaces:

Serializable, Iterator<StreamEvent>

Direct Known Subclasses:

ListEventHolder

public class SnapshotableStreamEventQueue
extends Object
implements Iterator<StreamEvent>, Serializable

The class to hold stream events in a queue and by managing its snapshots

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected StreamEvent	first
protected StreamEvent	last
protected StreamEvent	lastReturned
protected StreamEvent	previousToLastReturned

Constructor Summary

Constructors

Constructor and Description
SnapshotableStreamEventQueue(StreamEventClonerHolder eventClonerHolder)
SnapshotableStreamEventQueue(StreamEventClonerHolder eventClonerHolder, int operationChangeLogThreshold)

Method Summary

Modifier and Type	Method and Description
void	add(StreamEvent events)
void	clear()
boolean	equals(Object o)
StreamEvent	getFirst()
StreamEvent	getLast()
SnapshotState	getSnapshot()
int	hashCode()
boolean	hasNext() Returns true if the iteration has more elements.
StreamEvent	next() Returns the next element in the iteration.
void	overwrite(StreamEvent streamEvent)
StreamEvent	poll()
void	remove() Removes from the underlying collection the last element returned by the iterator (optional operation).
void	reset()
void	restore(SnapshotStateList snapshotStatelist)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Iterator

forEachRemaining

Field Detail

first

protected StreamEvent first

previousToLastReturned

protected StreamEvent previousToLastReturned

lastReturned

protected StreamEvent lastReturned

last

protected StreamEvent last

Constructor Detail

SnapshotableStreamEventQueue

public SnapshotableStreamEventQueue(StreamEventClonerHolder eventClonerHolder)

SnapshotableStreamEventQueue

public SnapshotableStreamEventQueue(StreamEventClonerHolder eventClonerHolder,
                                    int operationChangeLogThreshold)

Method Detail

add

public void add(StreamEvent events)

remove

public void remove()

Removes from the underlying collection the last element returned by the iterator (optional operation). This method can be called only once per call to next. The behavior of an iterator is unspecified if the underlying collection is modified while the iteration is in progress in any way other than by calling this method.

Specified by:

remove in interface Iterator<StreamEvent>

Throws:

UnsupportedOperationException - if the remove operation is not supported by this Iterator.

IllegalStateException - if the next method has not yet been called, or the remove method has already been called after the last call to the next method.

hasNext

public boolean hasNext()

Returns true if the iteration has more elements. (In other words, returns true if next would return an element rather than throwing an exception.)

Specified by:

hasNext in interface Iterator<StreamEvent>

Returns:

true if the iterator has more elements.

next

public StreamEvent next()

Returns the next element in the iteration.

Specified by:

next in interface Iterator<StreamEvent>

Returns:

the next element in the iteration.

Throws:

NoSuchElementException - iteration has no more elements.

clear

public void clear()

reset

public void reset()

getFirst

public StreamEvent getFirst()

getLast

public StreamEvent getLast()

poll

public StreamEvent poll()

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

getSnapshot

public SnapshotState getSnapshot()

restore

public void restore(SnapshotStateList snapshotStatelist)

overwrite

public void overwrite(StreamEvent streamEvent)