com.univocity.parsers.common.processor
Class RowWriterProcessorSwitch

java.lang.Object
  com.univocity.parsers.common.processor.RowWriterProcessorSwitch

All Implemented Interfaces:

RowWriterProcessor<Object>

Direct Known Subclasses:

OutputValueSwitch

public abstract class RowWriterProcessorSwitch
extends Object
implements RowWriterProcessor<Object>

A special RowWriterProcessor implementation that combines and allows switching among different RowWriterProcessors. Concrete implementations of this class are expected to implement the switchRowProcessor(T) method and analyze the input row to determine whether or not the current RowWriterProcessor implementation must be changed to handle a special circumstance (determined by the concrete implementation) such as a different row format. When the row writer processor is switched, the rowProcessorSwitched(RowWriterProcessor, RowWriterProcessor) will be called, and must be overridden, to notify the change to the user.

Constructor Summary

RowWriterProcessorSwitch()

Method Summary

protected abstract String	describeSwitch()
protected String[]	getHeaders() Returns the headers in use by the current row writer processor implementation, which can vary among row writer processors.
abstract String[]	getHeaders(Map headerMapping, Map mapInput) Returns the sequence of headers to use for processing an input record represented by a map A map of headers can be optionally provided to assign a name to the keys of the input map.
abstract String[]	getHeaders(Object input) Returns the sequence of headers to use for processing an input record.
protected int[]	getIndexes() Returns the indexes in use by the current row writer processor implementation, which can vary among row writer processors.
int	getMinimumRowLength() Returns the minimum row length based on the number of headers and index sizes
void	rowProcessorSwitched(RowWriterProcessor<?> from, RowWriterProcessor<?> to) Notifies a change of row writer processor implementation.
protected abstract RowWriterProcessor<?>	switchRowProcessor(Object row) Analyzes an output row to determine whether or not the row writer processor implementation must be changed
Object[]	write(Object input, String[] headers, int[] indexesToWrite) Converts the given input into an Object array that is suitable for writing.

Methods inherited from class java.lang.Object

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

Constructor Detail

RowWriterProcessorSwitch

public RowWriterProcessorSwitch()

Method Detail

switchRowProcessor

protected abstract RowWriterProcessor<?> switchRowProcessor(Object row)

Analyzes an output row to determine whether or not the row writer processor implementation must be changed

Parameters:

row - a record with data to be written to the output

Returns:

the row writer processor implementation to use. If it is not the same as the one used by the previous row, the returned row writer processor will be used, and the rowProcessorSwitched(RowWriterProcessor, RowWriterProcessor) method will be called.

getHeaders

protected String[] getHeaders()

Returns the headers in use by the current row writer processor implementation, which can vary among row writer processors. If null, the headers defined in CommonSettings.getHeaders() will be returned.

Returns:

the current sequence of headers to use.

getIndexes

protected int[] getIndexes()

Returns the indexes in use by the current row writer processor implementation, which can vary among row writer processors. If null, the indexes of fields that have been selected using CommonSettings.selectFields(String...) or CommonSettings.selectIndexes(Integer...) will be returned.

Returns:

the current sequence of indexes to use.

rowProcessorSwitched

public void rowProcessorSwitched(RowWriterProcessor<?> from,
                                 RowWriterProcessor<?> to)

Notifies a change of row writer processor implementation. Users are expected to override this method to receive the notification.

Parameters:

from - the row writer processor previously in use

to - the new row writer processor to use to continue processing the output rows.

getHeaders

public abstract String[] getHeaders(Map headerMapping,
                                    Map mapInput)

Returns the sequence of headers to use for processing an input record represented by a map A map of headers can be optionally provided to assign a name to the keys of the input map. This is useful when the input map has keys will generate unwanted header names.

Parameters:

headerMapping - an optional map associating keys of the rowData map with expected header names

mapInput - the record data

Returns:

the sequence of headers to use when processing the given input map.

getHeaders

public abstract String[] getHeaders(Object input)

Returns the sequence of headers to use for processing an input record.

Parameters:

input - the record data

Returns:

the sequence of headers to use when processing the given record.

describeSwitch

protected abstract String describeSwitch()

getMinimumRowLength

public final int getMinimumRowLength()

Returns the minimum row length based on the number of headers and index sizes

Returns:

the minimum length a row must have in order to be sent to the output

write

public Object[] write(Object input,
                      String[] headers,
                      int[] indexesToWrite)

Description copied from interface: RowWriterProcessor

Converts the given input into an Object array that is suitable for writing. Used by format-specific writers that extend AbstractWriter.

Specified by:

write in interface RowWriterProcessor<Object>

Parameters:

input - The original input record that must be converted into an Object array before writing to an output.

headers - All field names used to produce records in a given destination. May be null if no headers have been defined in CommonSettings.getHeaders()

indexesToWrite - The indexes of the headers that are actually being written. May be null if no fields have been selected using CommonSettings.selectFields(String...) or CommonSettings.selectIndexes(Integer...)

Returns:

an Object array that is suitable for writing. If null or an empty array is returned then the writer might either skip this value or write an empty record (if CommonSettings.getSkipEmptyLines() is false)

See Also:

CsvWriter, FixedWidthWriter, CommonSettings, AbstractWriter