gr.uoa.di.madgik.grs.reader

Interface IRecordReader<T extends Record>

All Superinterfaces:

Iterable<T>

All Known Implementing Classes:

ForwardReader, KeepAliveReader, RandomReader, RecordReaderDelegate

public interface IRecordReader<T extends Record>
extends Iterable<T>

Method Summary

Methods

Modifier and Type	Method and Description
int	availableRecords() The number of readily available for consumption Records.
void	close() Closes and disposes the underlying buffer.
long	currentRecord() The index of the last Record retrieved through the reader.
void	emit(BufferEvent event) Emits the provided event to the writer.
T	get() Retrieves the next available Record from the IBuffer.
T	get(long timeout, TimeUnit unit) Retrieves the next available Record from the IBuffer.
int	getCapacity() The underlying IBuffer capacity used.
int	getConcurrentPartialCapacity() The underlying IBuffer concurrent partial capacity used
long	getInactivityTimeout() Retrieves the Inactivity timeout set for the lifecycle management of the underlying IBuffer.
TimeUnit	getInactivityTimeUnit() Retrieves the Inactivity time unit set for the lifecycle management of the underlying IBuffer.
long	getIteratorTimeout() The timeout that is used by the Iterators that are created by this reader.
TimeUnit	getIteratorTimeUnit() The time unit that is used by the Iterators that are created by this reader.
RecordDefinition[]	getRecordDefinitions() Retrieves the RecordDefinitions that define the Records that are accessible through the reader.
IBuffer.Status	getStatus() Retrieves the status of the underlying IBuffer.
Iterator<T>	iterator()
BufferEvent	receive() Receives a previously emitted event from a writer.
long	seek(long len) Seeks the number of Records provided in the list of Records available.
void	setIteratorTimeout(long iteratorTimeout) The timeout that should be used by the Iterators that are created by this reader.
void	setIteratorTimeUnit(TimeUnit iteratorTimeUnit) The time unit that should be used by the Iterators that are created by this reader.
long	totalRecords() The number of total Records that have passed through the IBuffer this far.
boolean	waitAvailable(long timeout, TimeUnit unit) Makes sure that within the provided time frame, there is a Record that can be retrieved without blocking.

Method Detail

getRecordDefinitions

RecordDefinition[] getRecordDefinitions()
                                        throws GRS2ReaderException

Retrieves the RecordDefinitions that define the Records that are accessible through the reader.

Returns:

the RecordDefinitions as were provided by the corresponding writer

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.getRecordDefinitions()

getInactivityTimeout

long getInactivityTimeout()
                          throws GRS2ReaderException

Retrieves the Inactivity timeout set for the lifecycle management of the underlying IBuffer. This value should be interpreted in conjunction with the value of getInactivityTimeUnit().

Returns:

the inactivity timeout

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.getInactivityTimeout()

getInactivityTimeUnit

TimeUnit getInactivityTimeUnit()
                               throws GRS2ReaderException

Retrieves the Inactivity time unit set for the lifecycle management of the underlying IBuffer. This value should be interpreted in conjunction with the value of getInactivityTimeout()

Returns:

the inactivity time unit

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.getInactivityTimeUnit()

getCapacity

int getCapacity()
                throws GRS2ReaderException

The underlying IBuffer capacity used.

Returns:

the buffer capacity

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.getCapacity()

getConcurrentPartialCapacity

int getConcurrentPartialCapacity()
                                 throws GRS2ReaderException

The underlying IBuffer concurrent partial capacity used

Returns:

the concurrency partial record buffer capacity

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.getConcurrentPartialCapacity()

getStatus

IBuffer.Status getStatus()

Retrieves the status of the underlying IBuffer.

Returns:

the status of the underlying buffer

See Also:

IBuffer.getStatus()

close

void close()
           throws GRS2ReaderException

Closes and disposes the underlying buffer. After this method has been invoked, all associated resources are disposed.

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.close(), IBuffer.dispose()

totalRecords

long totalRecords()
                  throws GRS2ReaderException

The number of total Records that have passed through the IBuffer this far.

Returns:

the number of total Records that have passed through the IBuffer this far

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.totalRecords()

availableRecords

int availableRecords()
                     throws GRS2ReaderException

The number of readily available for consumption Records.

Returns:

the number of readily available for consumption records

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.availableRecords()

currentRecord

long currentRecord()
                   throws GRS2ReaderException

The index of the last Record retrieved through the reader.

Returns:

the index of the last Record retrieved through the reader

Throws:

GRS2ReaderException - the operation could not be completed because no records were retrieved yet

get

T get()
                     throws GRS2ReaderException

Retrieves the next available Record from the IBuffer. An explicit cast is performed to the type provided in the generic declaration of the reader.

Returns:

the retrieved Record or null if none was readily available

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.get()

get

T get(long timeout,
    TimeUnit unit)
                     throws GRS2ReaderException

Retrieves the next available Record from the IBuffer. An explicit cast is performed to the type provided in the generic declaration of the reader. If no record is readily available the reader will block for a maximum of timeout unit units of time waiting for a record to become available or until the IBuffer uses the IBuffer.getReaderImmediateNotificationObject() to notify blocked readers.

Parameters:

timeout - the timeout to wait for

unit - the unit of time to use to interpret the timeout value

Returns:

the Record retrieved, or null if the timeout expired without a Record becoming available

Throws:

GRS2ReaderException - the operation could not be completed

See Also:

IBuffer.get()

waitAvailable

boolean waitAvailable(long timeout,
                    TimeUnit unit)
                      throws GRS2ReaderException

Makes sure that within the provided time frame, there is a Record that can be retrieved without blocking. If the timeout defined expires and no Record has been made available, false is returned. Otherwise, or if there are already available Records, true is returned.

Parameters:

timeout - the timeout value interpreted in conjunction with the unit value

unit - the time unit to use to interpret the timeout value

Returns:

true if there is a Record available before the timeout has expired, false otherwise

Throws:

GRS2ReaderException - the operation could not be completed

setIteratorTimeout

void setIteratorTimeout(long iteratorTimeout)

The timeout that should be used by the Iterators that are created by this reader. This value is interpreted in conjunction with the value of getIteratorTimeUnit()

Parameters:

iteratorTimeout - the timeout

setIteratorTimeUnit

void setIteratorTimeUnit(TimeUnit iteratorTimeUnit)

The time unit that should be used by the Iterators that are created by this reader. This value is interpreted in conjunction with the value of getIteratorTimeout()

Parameters:

iteratorTimeUnit - the time unit

getIteratorTimeout

long getIteratorTimeout()
                        throws GRS2ReaderException

The timeout that is used by the Iterators that are created by this reader. This value is interpreted in conjunction with the value of getIteratorTimeUnit().

Returns:

the timeout

Throws:

GRS2ReaderException

getIteratorTimeUnit

TimeUnit getIteratorTimeUnit()

The time unit that is used by the Iterators that are created by this reader. This value is interpreted in conjunction with the value of getIteratorTimeout()

Returns:

the time unit

iterator

Iterator<T> iterator()

Specified by:

iterator in interface Iterable<T extends Record>

seek

long seek(long len)
          throws GRS2ReaderException

Seeks the number of Records provided in the list of Records available. Depending on the actual IRecordReader implementation, forward and/or backward seeks may be supported.

Parameters:

len - the number of Record}s to skip

Returns:

the number of Records actually skipped

Throws:

GRS2ReaderException - the operation could not be completed

emit

void emit(BufferEvent event)
          throws GRS2ReaderException,
                 GRS2ReaderInvalidArgumentException

Emits the provided event to the writer. The source of the event is set to BufferEvent.EventSource.Reader.

Parameters:

event - the event to send to the writer

Throws:

GRS2ReaderException - the operation could not be completed

GRS2ReaderInvalidArgumentException - the event provided cannot be null

receive

BufferEvent receive()
                    throws GRS2ReaderException

Receives a previously emitted event from a writer.

Returns:

the event received or null if no pending events exist

Throws:

GRS2ReaderException - the operation could not be completed