org.datavec.api.records.reader.impl.regex

Class RegexLineRecordReader

java.lang.Object

org.datavec.api.records.reader.BaseRecordReader

org.datavec.api.records.reader.impl.LineRecordReader

org.datavec.api.records.reader.impl.regex.RegexLineRecordReader

All Implemented Interfaces:

Closeable, Serializable, AutoCloseable, Configurable, RecordReader

public class RegexLineRecordReader
extends LineRecordReader

RegexLineRecordReader: Read a file, one line at a time, and split it into fields using a regex. Specifically, we are using Pattern and Matcher.
To load an entire file using a Example: Data in format "2016-01-01 23:59:59.001 1 DEBUG First entry message!"
using regex String "(\\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2}\\.\\d{3}) (\\d+) ([A-Z]+) (.*)"
would be split into 4 Text writables: ["2016-01-01 23:59:59.001", "1", "DEBUG", "First entry message!"]

Author:

Alex Black

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	SKIP_NUM_LINES

Fields inherited from class org.datavec.api.records.reader.impl.LineRecordReader

conf, inputSplit, lineIndex, locations, splitIndex

Fields inherited from class org.datavec.api.records.reader.BaseRecordReader

listeners

Fields inherited from interface org.datavec.api.records.reader.RecordReader

APPEND_LABEL, LABELS, NAME_SPACE

Constructor Summary

Constructors

Constructor and Description
RegexLineRecordReader(String regex, int skipNumLines)

Method Summary

Modifier and Type	Method and Description
void	initialize(Configuration conf, InputSplit split) Called once at initialization.
List<Record>	loadFromMetaData(List<RecordMetaData> recordMetaDatas) Load multiple records from the given a list of RecordMetaData instances
Record	loadFromMetaData(RecordMetaData recordMetaData) Load a single record from the given RecordMetaData instance Note: that for data that isn't splittable (i.e., text data that needs to be scanned/split), it is more efficient to load multiple records at once using RecordReader.loadFromMetaData(List)
List<Writable>	next() Get the next record
Record	nextRecord() Similar to RecordReader.next(), but returns a Record object, that may include metadata such as the source of the data
List<Writable>	record(URI uri, DataInputStream dataInputStream) Load the record from the given DataInputStream Unlike RecordReader.next() the internal state of the RecordReader is not modified Implementations of this method should not close the DataInputStream
void	reset() Reset record reader iterator

Methods inherited from class org.datavec.api.records.reader.impl.LineRecordReader

close, closeIfRequired, getConf, getIterator, getLabels, hasNext, initialize, onLocationOpen, setConf

Methods inherited from class org.datavec.api.records.reader.BaseRecordReader

batchesSupported, getListeners, invokeListeners, next, setListeners, setListeners

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SKIP_NUM_LINES

public static final String SKIP_NUM_LINES

Constructor Detail

RegexLineRecordReader

public RegexLineRecordReader(String regex,
                             int skipNumLines)

Method Detail

initialize

public void initialize(Configuration conf,
                       InputSplit split)
                throws IOException,
                       InterruptedException

Description copied from interface: RecordReader

Called once at initialization.

Specified by:

initialize in interface RecordReader

Overrides:

initialize in class LineRecordReader

Parameters:

conf - a configuration for initialization

split - the split that defines the range of records to read

Throws:

IOException

InterruptedException

next

public List<Writable> next()

Description copied from interface: RecordReader

Get the next record

Specified by:

next in interface RecordReader

Overrides:

next in class LineRecordReader

Returns:

record

public List<Writable> record(URI uri,
                             DataInputStream dataInputStream)
                      throws IOException

Description copied from interface: RecordReader

Load the record from the given DataInputStream Unlike RecordReader.next() the internal state of the RecordReader is not modified Implementations of this method should not close the DataInputStream

Specified by:

record in interface RecordReader

Overrides:

record in class LineRecordReader

Throws:

IOException - if error occurs during reading from the input stream

reset

public void reset()

Description copied from interface: RecordReader

Reset record reader iterator

Specified by:

reset in interface RecordReader

Overrides:

reset in class LineRecordReader

nextRecord

public Record nextRecord()

Description copied from interface: RecordReader

Similar to RecordReader.next(), but returns a Record object, that may include metadata such as the source of the data

Specified by:

nextRecord in interface RecordReader

Overrides:

nextRecord in class LineRecordReader

Returns:

next record

loadFromMetaData

public Record loadFromMetaData(RecordMetaData recordMetaData)
                        throws IOException

Description copied from interface: RecordReader

Load a single record from the given RecordMetaData instance
Note: that for data that isn't splittable (i.e., text data that needs to be scanned/split), it is more efficient to load multiple records at once using RecordReader.loadFromMetaData(List)

Specified by:

loadFromMetaData in interface RecordReader

Overrides:

loadFromMetaData in class LineRecordReader

Parameters:

recordMetaData - Metadata for the record that we want to load from

Returns:

Single record for the given RecordMetaData instance

Throws:

IOException - If I/O error occurs during loading

loadFromMetaData

public List<Record> loadFromMetaData(List<RecordMetaData> recordMetaDatas)
                              throws IOException

Description copied from interface: RecordReader

Load multiple records from the given a list of RecordMetaData instances

Specified by:

loadFromMetaData in interface RecordReader

Overrides:

loadFromMetaData in class LineRecordReader

Parameters:

recordMetaDatas - Metadata for the records that we want to load from

Returns:

Multiple records for the given RecordMetaData instances

Throws:

IOException - If I/O error occurs during loading