AbstractIterator

java.lang.Object

org.apache.lucene.internal.hppc.AbstractIterator<E>

All Implemented Interfaces:: Iterator<E>

Direct Known Subclasses:: CharHashSet.EntryIterator, CharObjectHashMap.EntryIterator, CharObjectHashMap.KeysIterator, CharObjectHashMap.ValuesIterator, FloatArrayList.ValueIterator, IntArrayList.ValueIterator, IntDoubleHashMap.EntryIterator, IntDoubleHashMap.KeysIterator, IntDoubleHashMap.ValuesIterator, IntFloatHashMap.EntryIterator, IntFloatHashMap.KeysIterator, IntFloatHashMap.ValuesIterator, IntHashSet.EntryIterator, IntIntHashMap.EntryIterator, IntIntHashMap.KeysIterator, IntIntHashMap.ValuesIterator, IntObjectHashMap.EntryIterator, IntObjectHashMap.KeysIterator, IntObjectHashMap.ValuesIterator, LongArrayList.ValueIterator, LongFloatHashMap.EntryIterator, LongFloatHashMap.KeysIterator, LongFloatHashMap.ValuesIterator, LongHashSet.EntryIterator, LongIntHashMap.EntryIterator, LongIntHashMap.KeysIterator, LongIntHashMap.ValuesIterator, LongObjectHashMap.EntryIterator, LongObjectHashMap.KeysIterator, LongObjectHashMap.ValuesIterator

public abstract class AbstractIterator<E> extends Object implements Iterator<E>

Simplifies the implementation of iterators a bit. Modeled loosely after Google Guava's API.

Forked from com.carrotsearch.hppc.AbstractIterator

Field Summary

Fields

Modifier and Type

Field

Description

private static final int

AT_END

private static final int

CACHED

private E

nextElement

The next element to be returned from next() if fetched.

private static final int

NOT_CACHED

private int

state

Current iterator state.
Constructor Summary

Constructors

Constructor

Description

AbstractIterator()
Method Summary

Modifier and Type

Method

Description

protected final E

done()

Call when done.

protected abstract E

fetch()

Fetch next element.

boolean

hasNext()

E

next()

void

remove()

Default implementation throws UnsupportedOperationException.

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

Field Details
- NOT_CACHED
  
  private static final int NOT_CACHED
  See Also:
  
  Constant Field Values
- CACHED
  
  private static final int CACHED
  See Also:
  
  Constant Field Values
- AT_END
  
  private static final int AT_END
  See Also:
  
  Constant Field Values
- state
  
  private int state
  
  Current iterator state.
- nextElement
  
  private E nextElement
  
  The next element to be returned from next() if fetched.
Constructor Details
- AbstractIterator
  
  public AbstractIterator()
Method Details
- hasNext
  
  public boolean hasNext()
  
  Specified by:
  
  hasNext in interface Iterator<E>
- next
  
  public E next()
  
  Specified by:
  
  next in interface Iterator<E>
- remove
  
  public void remove()
  
  Default implementation throws UnsupportedOperationException.
  
  Specified by:
  
  remove in interface Iterator<E>
- fetch
  
  protected abstract E fetch()
  
  Fetch next element. The implementation must return done() when all elements have been fetched.
  
  Returns:
  
  Returns the next value for the iterator or chain-calls done().
- done
  
  protected final E done()
  
  Call when done.
  
  Returns:
  
  Returns a unique sentinel value to indicate end-of-iteration.