Package com.datastax.astra.client.model

Class DistinctIterator<T,F>

java.lang.Object

com.datastax.astra.client.model.DistinctIterator<T,F>

Type Parameters:

T - working class representing the document

F - working class representing the field to extract from the document.

All Implemented Interfaces:

Iterator<F>

public class DistinctIterator<T,F>
extends Object
implements Iterator<F>

Iterator to retrieve distinct values of a field in a document.

Constructor Summary

Constructors

Constructor	Description
DistinctIterator(PageableIterable<T> findIterable, String fieldName, Class<F> fieldClass)	Starting the cursor on an iterable to fetch more pages.

Method Summary

Modifier and Type	Method	Description
boolean	hasNext()
F	next()	Implementing a logic of iterator combining current page and paging.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

Constructor Details

DistinctIterator

public DistinctIterator(PageableIterable<T> findIterable,
 String fieldName,
 Class<F> fieldClass)

Starting the cursor on an iterable to fetch more pages.

Parameters:

findIterable - iterable

fieldName - name of the field to pick

fieldClass - type of the field to pick

Method Details

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T>

next

public F next()

Implementing a logic of iterator combining current page and paging. A local iterator is started on elements of the processing page. If the local iterator is exhausted, the flag 'nextPageState' can tell us is there are more elements to retrieve. if 'nextPageState' is not null the next page is fetch at Iterable level and the local iterator is reinitialized on the new page.

Specified by:

next in interface Iterator<T>

Returns:

next document in the iterator