com.googlecode.n_orm.utils

Class AggregatingIterator

java.lang.Object

com.googlecode.n_orm.utils.AggregatingIterator

All Implemented Interfaces:

CloseableIterator<Row>, CloseableKeyIterator, Closeable, AutoCloseable, Iterator<Row>

public class AggregatingIterator
extends Object
implements CloseableKeyIterator

An CloseableIterator composite able to iterate over a set of CloseableIterators. Elements are selected from composed iterators so that they are iterated in an ordered way. In case an element with same id is found from different iterators, an exception is thrown, unless merge(Row, CloseableKeyIterator, Row, CloseableKeyIterator) is overridden.

Constructor Summary

Constructors

Constructor and Description
AggregatingIterator()

Method Summary

Modifier and Type	Method and Description
void	addIterator(CloseableKeyIterator it) Adds an iterator to the list of iterators to be explored.
void	close()
boolean	hasNext()
Row	merge(Row r1, CloseableKeyIterator it1, Row r2, CloseableKeyIterator it2)
Row	next()
void	remove()

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

Constructor Detail

AggregatingIterator

public AggregatingIterator()

Method Detail

addIterator

public void addIterator(CloseableKeyIterator it)

Adds an iterator to the list of iterators to be explored.

Throws:

IllegalStateException - in case the iteration has started using hasNext() or next().

close

public void close()

Specified by:

close in interface CloseableIterator<Row>

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<Row>

next

public Row next()

Specified by:

next in interface Iterator<Row>

remove

public void remove()

Specified by:

remove in interface Iterator<Row>

Throws:

UnsupportedOperationException - in any case

merge

public Row merge(Row r1,
                 CloseableKeyIterator it1,
                 Row r2,
                 CloseableKeyIterator it2)
          throws Exception

Throws:

Exception