Package org.apache.commons.collections4.iterators

Class UnmodifiableMapIterator<K,V>

java.lang.Object

org.apache.commons.collections4.iterators.UnmodifiableMapIterator<K,V>

Type Parameters:

K - The type of keys.

V - The type of mapped values.

All Implemented Interfaces:

Iterator<K>, MapIterator<K,V>, Unmodifiable

public final class UnmodifiableMapIterator<K,V>
extends Object
implements MapIterator<K,V>, Unmodifiable

Decorates a map iterator such that it cannot be modified.

Attempts to modify it will result in an UnsupportedOperationException.

Since:

3.0

Method Summary

Modifier and Type	Method	Description
K	getKey()	Gets the current key, which is the key returned by the last call to next().
V	getValue()	Gets the current value, which is the value associated with the last key returned by next().
boolean	hasNext()	Checks to see if there are more entries still to be iterated.
K	next()	Gets the next key from the Map.
void	remove()	Always throws UnsupportedOperationException.
V	setValue(V value)	Always throws UnsupportedOperationException.
static <K, V> MapIterator<K,V>	unmodifiableMapIterator(MapIterator<? extends K,? extends V> iterator)	Decorates the specified iterator such that it cannot be modified.

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

Method Details

unmodifiableMapIterator

public static <K,
V> MapIterator<K,V> unmodifiableMapIterator(MapIterator<? extends K,? extends V> iterator)

Decorates the specified iterator such that it cannot be modified.

Type Parameters:

K - The key type.

V - The value type.

Parameters:

iterator - The iterator to decorate.

Returns:

A new unmodifiable map iterator.

Throws:

NullPointerException - If the iterator is null.

getKey

public K getKey()

Description copied from interface: MapIterator

Gets the current key, which is the key returned by the last call to next().

Specified by:

getKey in interface MapIterator<K,V>

Returns:

The current key.

getValue

public V getValue()

Description copied from interface: MapIterator

Gets the current value, which is the value associated with the last key returned by next().

Specified by:

getValue in interface MapIterator<K,V>

Returns:

The current value.

hasNext

public boolean hasNext()

Description copied from interface: MapIterator

Checks to see if there are more entries still to be iterated.

Specified by:

hasNext in interface Iterator<K>

Specified by:

hasNext in interface MapIterator<K,V>

Returns:

true if the iterator has more elements

next

public K next()

Description copied from interface: MapIterator

Gets the next key from the Map.

Specified by:

next in interface Iterator<K>

Specified by:

next in interface MapIterator<K,V>

Returns:

The next key in the iteration.

remove

public void remove()

Always throws UnsupportedOperationException.

Specified by:

remove in interface Iterator<K>

Specified by:

remove in interface MapIterator<K,V>

Throws:

UnsupportedOperationException - Always thrown.

setValue

public V setValue(V value)

Always throws UnsupportedOperationException.

Specified by:

setValue in interface MapIterator<K,V>

Parameters:

value - Ignored.

Returns:

The previous value.

Throws:

UnsupportedOperationException - Always thrown.