Package org.apache.commons.collections

Interface MapIterator

  • All Superinterfaces:
    Iterator
    All Known Subinterfaces:
    OrderedMapIterator
    All Known Implementing Classes:
    AbstractMapIteratorDecorator, AbstractOrderedMapIteratorDecorator, EmptyMapIterator, EmptyOrderedMapIterator, EntrySetMapIterator, UnmodifiableMapIterator, UnmodifiableOrderedMapIterator
    @Deprecated(since="2021-04-30")
public interface MapIterator
extends Iterator
    Deprecated.
    Commons Collections 3 is in maintenance mode. Commons Collections 4 should be used instead.
    Defines an iterator that operates over a Map.

    This iterator is a special version designed for maps. It can be more efficient to use this rather than an entry set iterator where the option is available, and it is certainly more convenient.

    A map that provides this interface may not hold the data internally using Map Entry objects, thus this interface can avoid lots of object creation.

    In use, this iterator iterates through the keys in the map. After each call to next(), the getValue() method provides direct access to the value. The value can also be set using setValue(). 

      MapIterator it = map.mapIterator();
  while (it.hasNext()) {
    Object key = it.next();
    Object value = it.getValue();
    it.setValue(newValue);
  }
    Since:
    Commons Collections 3.0

    • Method Summary

      All Methods Instance Methods Abstract Methods Deprecated Methods 
      Modifier and Type Method Description
      Object getKey()
      Deprecated.
      Gets the current key, which is the key returned by the last call to next().
      Object getValue()
      Deprecated.
      Gets the current value, which is the value associated with the last key returned by next().
      boolean hasNext()
      Deprecated.
      Checks to see if there are more entries still to be iterated.
      Object next()
      Deprecated.
      Gets the next key from the Map.
      void remove()
      Deprecated.
      Removes the last returned key from the underlying Map (optional operation).
      Object setValue​(Object value)
      Deprecated.
      Sets the value associated with the current key (optional operation).

    • Method Detail

      • hasNext

        boolean hasNext()
        Deprecated.
        Checks to see if there are more entries still to be iterated.
        Specified by:
        hasNext in interface Iterator
        Returns:
        true if the iterator has more elements

      • next

        Object next()
        Deprecated.
        Gets the next key from the Map.
        Specified by:
        next in interface Iterator
        Returns:
        the next key in the iteration
        Throws:
        NoSuchElementException - if the iteration is finished

      • getKey

        Object getKey()
        Deprecated.
        Gets the current key, which is the key returned by the last call to next().
        Returns:
        the current key
        Throws:
        IllegalStateException - if next() has not yet been called

      • getValue

        Object getValue()
        Deprecated.
        Gets the current value, which is the value associated with the last key returned by next().
        Returns:
        the current value
        Throws:
        IllegalStateException - if next() has not yet been called

      • remove

        void remove()
        Deprecated.
        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
        Throws:
        UnsupportedOperationException - if remove is not supported by the map
        IllegalStateException - if next() has not yet been called
        IllegalStateException - if remove() has already been called since the last call to next()