Package org.springframework.batch.item.file.transform

Class ExtractorLineAggregator<T>

java.lang.Object

org.springframework.batch.item.file.transform.ExtractorLineAggregator<T>

All Implemented Interfaces:

LineAggregator<T>

Direct Known Subclasses:

DelimitedLineAggregator, FormatterLineAggregator

public abstract class ExtractorLineAggregator<T>
extends Object
implements LineAggregator<T>

An abstract LineAggregator implementation that utilizes a FieldExtractor to convert the incoming object to an array of its parts. Extending classes must decide how those parts will be aggregated together.

Since:

2.0

Author:

Dan Garrette

Constructor Summary

Constructors

Constructor	Description
ExtractorLineAggregator()

Method Summary

Modifier and Type	Method	Description
String	aggregate(T item)	Extract fields from the given item using the FieldExtractor and then aggregate them.
protected abstract String	doAggregate(Object[] fields)	Aggregate provided fields into single String.
void	setFieldExtractor(FieldExtractor<T> fieldExtractor)	Public setter for the field extractor responsible for splitting an input object up into an array of objects.

Methods inherited from class java.lang.Object

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

Constructor Details

ExtractorLineAggregator

public ExtractorLineAggregator()

Method Details

setFieldExtractor

public void setFieldExtractor(FieldExtractor<T> fieldExtractor)

Public setter for the field extractor responsible for splitting an input object up into an array of objects. Defaults to PassThroughFieldExtractor.

Parameters:

fieldExtractor - The field extractor to set

aggregate

public String aggregate(T item)

Extract fields from the given item using the FieldExtractor and then aggregate them. Any null field returned by the extractor will be replaced by an empty String. Null items are not allowed.

Specified by:

aggregate in interface LineAggregator<T>

Parameters:

item - values to be converted

Returns:

string

See Also:

• LineAggregator.aggregate(java.lang.Object)

doAggregate

protected abstract String doAggregate(Object[] fields)

Aggregate provided fields into single String.

Parameters:

fields - An array of the fields that must be aggregated

Returns:

aggregated string