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()
    Removes the last returned key from the underlying Map (optional operation).
    V
    setValue(V value)
    Sets the value associated with the current key (optional operation).
    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()
      Description copied from interface: MapIterator
      Removes the last returned key from the underlying Map (optional operation).

      This method can be called once per call to next().

      Specified by:
      remove in interface Iterator<K>
      Specified by:
      remove in interface MapIterator<K,V>

    • setValue

      public V setValue(V value)
      Description copied from interface: MapIterator
      Sets the value associated with the current key (optional operation).
      Specified by:
      setValue in interface MapIterator<K,V>
      Parameters:
      value - the new value
      Returns:
      the previous value