com.northconcepts.datapipeline.core

Class AbstractReader

java.lang.Object

com.northconcepts.datapipeline.core.DataObject

com.northconcepts.datapipeline.core.Endpoint

com.northconcepts.datapipeline.core.DataEndpoint

com.northconcepts.datapipeline.core.DataReader

com.northconcepts.datapipeline.core.AbstractReader

Direct Known Subclasses:

ExcelReader, ParsingReader, TextReader

public abstract class AbstractReader
extends DataReader

Abstract super-class, with some common logic, for reading records. The only method subclasses must implement is fillRecord(Record).

Nested Class Summary

Nested classes/interfaces inherited from class com.northconcepts.datapipeline.core.DataEndpoint

DataEndpoint.State

Field Summary

Fields

Modifier and Type	Field and Description
protected Record	currentRecord
protected String[]	fieldNames
protected int	lastRow
protected int	startingRow

Fields inherited from class com.northconcepts.datapipeline.core.DataReader

fieldLineage, recordLineage

Fields inherited from class com.northconcepts.datapipeline.core.DataEndpoint

lastRecord, PRODUCT, PRODUCT_VERSION, VENDOR, XML_INPUT_FACTORY_KEY

Fields inherited from class com.northconcepts.datapipeline.core.Endpoint

BUFFER_SIZE, captureElapsedTime, DEFAULT_READ_BUFFER_SIZE

Fields inherited from class com.northconcepts.datapipeline.core.DataObject

id, log, name, TIMESTAMP_FORMAT

Constructor Summary

Constructors

Constructor and Description
AbstractReader()

Method Summary

Modifier and Type	Method and Description
DataException	addExceptionProperties(DataException exception) Adds this endpoint's current state to a DataException.
protected abstract boolean	fillRecord(Record record)
String[]	getFieldNames()
int	getLastRow()
int	getStartingRow()
boolean	isFieldNamesInFirstRow()
boolean	isSkipEmptyRows() Indicates that rows with only null values should not be returned by the reader (default is false).
void	open() Makes this endpoint ready for reading or writing.
Record	read() Reads the next record from this DataReader and increases the record-count by 1.
protected Record	readImpl() Overridden by subclasses to read the next record from this DataReader.
AbstractReader	setFieldNames(Collection<String> fieldNames)
AbstractReader	setFieldNames(String... fieldNames)
AbstractReader	setFieldNamesInFirstRow(boolean fieldNamesInFirstRow)
AbstractReader	setLastRow(int lastRow)
AbstractReader	setSkipEmptyRows(boolean skipEmptyRows) Indicates that rows with only null values should not be returned by the reader (default is false).
AbstractReader	setStartingRow(int startingRow)

Methods inherited from class com.northconcepts.datapipeline.core.DataReader

addLineage, available, getBufferSize, getNestedEndpoint, getNestedReader, getRootEndpoint, getRootReader, isExhausted, isLineageSupported, isSaveLineage, peek, pop, push, setSaveLineage, skip

Methods inherited from class com.northconcepts.datapipeline.core.DataEndpoint

close, decrementRecordCount, enableJmx, getLastRecord, getRecordCount, getRecordCountAsBigInteger, getRecordCountAsString, incrementRecordCount, isRecordCountBigInteger, resetRecordCount, toString

Methods inherited from class com.northconcepts.datapipeline.core.Endpoint

addElapsedtime, assertClosed, assertNotOpened, assertOpened, finalize, getClosedOn, getDescription, getElapsedTime, getElapsedTimeAsString, getOpenedOn, getOpenElapsedTime, getOpenElapsedTimeAsString, getSelfTime, getSelfTimeAsString, getState, isCaptureElapsedTime, isClosed, isOpen, setCaptureElapsedTime, setDescription

Methods inherited from class com.northconcepts.datapipeline.core.DataObject

exception, exception, exception, getId, getName, resetID

Methods inherited from class java.lang.Object

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

Field Detail

fieldNames

protected String[] fieldNames

currentRecord

protected Record currentRecord

startingRow

protected int startingRow

lastRow

protected int lastRow

Constructor Detail

AbstractReader

public AbstractReader()

Method Detail

addExceptionProperties

public DataException addExceptionProperties(DataException exception)

Description copied from class: Endpoint

Adds this endpoint's current state to a DataException. Since this method is called whenever an exception is thrown, subclasses should override it to add their specific information.

Overrides:

addExceptionProperties in class DataReader

isFieldNamesInFirstRow

public boolean isFieldNamesInFirstRow()

setFieldNamesInFirstRow

public AbstractReader setFieldNamesInFirstRow(boolean fieldNamesInFirstRow)

getFieldNames

public String[] getFieldNames()

setFieldNames

public AbstractReader setFieldNames(String... fieldNames)

setFieldNames

public AbstractReader setFieldNames(Collection<String> fieldNames)

setStartingRow

public AbstractReader setStartingRow(int startingRow)

getStartingRow

public int getStartingRow()

setLastRow

public AbstractReader setLastRow(int lastRow)

getLastRow

public int getLastRow()

setSkipEmptyRows

public AbstractReader setSkipEmptyRows(boolean skipEmptyRows)

Indicates that rows with only null values should not be returned by the reader (default is false).

isSkipEmptyRows

public boolean isSkipEmptyRows()

Indicates that rows with only null values should not be returned by the reader (default is false).

open

public void open()
          throws DataException

Description copied from class: DataEndpoint

Makes this endpoint ready for reading or writing.

Overrides:

open in class DataEndpoint

Throws:

DataException

read

public Record read()
            throws DataException

Description copied from class: DataReader

Reads the next record from this DataReader and increases the record-count by 1. This method will first read any pushed (DataReader.push(Record)) records before reading from the underlying source.

If no record is available, null will be returned. This method blocks until a record is available, the end of the stream is reached, or an exception is thrown.

Any exception raised while reading will be converted to a DataException using DataObject.exception(Throwable).

Subclasses generally do not need to override this method, instead they should implement DataReader.readImpl().

Overrides:

read in class DataReader

Throws:

DataException

See Also:

DataReader.push(Record), DataReader.peek(int), DataReader.read()

readImpl

protected Record readImpl()
                   throws Throwable

Description copied from class: DataReader

Overridden by subclasses to read the next record from this DataReader. The default implementation of DataReader.read() now insures that this method will not be called again after it returns a null.

If no record is available, null will be returned.

Specified by:

readImpl in class DataReader

Throws:

Throwable

fillRecord

protected abstract boolean fillRecord(Record record)
                               throws Throwable

Throws:

Throwable