GroupFirst (Data Pipeline JavaDoc)

java.lang.Object

com.northconcepts.datapipeline.group.GroupOperation<Object>

com.northconcepts.datapipeline.group.operation.GroupFirst

public class GroupFirst extends GroupOperation<Object>

A GroupOperation that returns the first value of the source field in each group (the first non-null value when excludeNulls is set).

Constructor Summary

Constructors

Constructor

Description

GroupFirst(FieldPath sourceFieldName)

GroupFirst(FieldPath sourceFieldName, FieldPath targetFieldName)

GroupFirst(FieldPath sourceFieldName, FieldPath targetFieldName, boolean excludeNulls)

GroupFirst(String sourceFieldName)

GroupFirst(String sourceFieldName, String targetFieldName)

GroupFirst(String sourceFieldName, String targetFieldName, boolean excludeNulls)
Method Summary

Modifier and Type

Method

Description

protected GroupOperationField<Object>

createField()

Creates the accumulator that computes this operation's result for one group; called once per group in each window.

Methods inherited from class com.northconcepts.datapipeline.group.GroupOperation
getExcludeNulls, getFilter, getSourceFieldName, getSourceFieldPath, getTargetFieldName, getTargetFieldPath, setExcludeNulls, setFilter, setTargetFieldName, toString

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details
- GroupFirst
  
  public GroupFirst(String sourceFieldName)
- GroupFirst
  
  public GroupFirst(FieldPath sourceFieldName)
- GroupFirst
  
  public GroupFirst(String sourceFieldName, String targetFieldName)
- GroupFirst
  
  public GroupFirst(FieldPath sourceFieldName, FieldPath targetFieldName)
- GroupFirst
  
  public GroupFirst(String sourceFieldName, String targetFieldName, boolean excludeNulls)
- GroupFirst
  
  public GroupFirst(FieldPath sourceFieldName, FieldPath targetFieldName, boolean excludeNulls)
Method Details
- createField
  
  protected GroupOperationField<Object> createField()
  
  Description copied from class: GroupOperation
  
  Creates the accumulator that computes this operation's result for one group; called once per group in each window.
  
  Specified by:
  
  createField in class GroupOperation<Object>