Package org.apache.commons.collections4.iterators

Class EmptyMapIterator<K,V>

java.lang.Object
org.apache.commons.collections4.iterators.AbstractEmptyMapIterator<K,V>
org.apache.commons.collections4.iterators.EmptyMapIterator<K,V>
Type Parameters:
K - the type of keys
V - the type of mapped values
All Implemented Interfaces:
Iterator<K>, MapIterator<K,V>, ResettableIterator<K>
public class EmptyMapIterator<K,V> extends AbstractEmptyMapIterator<K,V> implements MapIterator<K,V>
Provides an implementation of an empty map iterator.
Since:
3.1

  • Field Summary Link icon

    Fields
    Modifier and Type
    Field
    Description
    static final MapIterator
    INSTANCE
    Singleton instance of the iterator.

  • Constructor Summary Link icon

    Constructors
    Modifier
    Constructor
    Description
    protected
    EmptyMapIterator()
    Constructs a new instance.

  • Method Summary Link icon

    Modifier and Type
    Method
    Description
    void
    add(K ignored)
    Deprecated.
    Will be removed in 5.0 without replacement.
    static <K, V> MapIterator<K,V>
    emptyMapIterator()
    Gets a typed instance of the iterator.
    boolean
    hasNext()
    Always returns false, this iterator contains no elements.
    boolean
    hasPrevious()
    Always returns false, this iterator contains no elements.
    K
    next()
    Always throws IllegalStateException, this iterator contains no elements.
    int
    nextIndex()
    Always returns 0, this iterator contains no elements.
    K
    previous()
    Always throws IllegalStateException, this iterator contains no elements.
    int
    previousIndex()
    Always returns -1, this iterator contains no elements.
    void
    remove()
    Always throws IllegalStateException, this iterator contains no elements.
    void
    reset()
    Resets the iterator back to the position at which the iterator was created.
    void
    set(K ignored)
    Always throws IllegalStateException, this iterator contains no elements.

    Methods inherited from class org.apache.commons.collections4.iterators.AbstractEmptyMapIterator Link icon

    getKey, getValue, setValue

    Methods inherited from class java.lang.Object Link icon

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    Methods inherited from interface java.util.Iterator Link icon

    forEachRemaining

    Methods inherited from interface org.apache.commons.collections4.MapIterator Link icon

    getKey, getValue, hasNext, next, remove, setValue

  • Field Details Link icon

    • INSTANCE Link icon

      public static final MapIterator INSTANCE
      Singleton instance of the iterator.
      Since:
      3.1

  • Constructor Details Link icon

  • Method Details Link icon

    • emptyMapIterator Link icon

      public static <K, V> MapIterator<K,V> emptyMapIterator()
      Gets a typed instance of the iterator.
      Type Parameters:
      K - the key type
      V - the value type
      Returns:
      MapIterator<K, V>

    • add Link icon

      @Deprecated public void add(K ignored)
      Deprecated.
      Will be removed in 5.0 without replacement.
      Always throws UnsupportedOperationException.
      Parameters:
      ignored - ignore.
      Throws:
      UnsupportedOperationException - Always thrown.

    • hasNext Link icon

      public boolean hasNext()
      Always returns false, this iterator contains no elements.
      Specified by:
      hasNext in interface Iterator<E>
      Returns:
      Always false.

    • hasPrevious Link icon

      public boolean hasPrevious()
      Always returns false, this iterator contains no elements.
      Returns:
      Always false.

    • next Link icon

      public K next()
      Always throws IllegalStateException, this iterator contains no elements.
      Specified by:
      next in interface Iterator<E>
      Returns:
      Always throws IllegalStateException.
      Throws:
      IllegalStateException - Always thrown.

    • nextIndex Link icon

      public int nextIndex()
      Always returns 0, this iterator contains no elements.
      Returns:
      Always returns 0.

    • previous Link icon

      public K previous()
      Always throws IllegalStateException, this iterator contains no elements.
      Returns:
      Always throws IllegalStateException.
      Throws:
      IllegalStateException - Always thrown.

    • previousIndex Link icon

      public int previousIndex()
      Always returns -1, this iterator contains no elements.
      Returns:
      Always returns -1.

    • remove Link icon

      public void remove()
      Always throws IllegalStateException, this iterator contains no elements.
      Specified by:
      remove in interface Iterator<E>
      Throws:
      IllegalStateException - Always thrown.

    • reset Link icon

      public void reset()
      Description copied from interface: ResettableIterator
      Resets the iterator back to the position at which the iterator was created.
      Specified by:
      reset in interface ResettableIterator<E>

    • set Link icon

      public void set(K ignored)
      Always throws IllegalStateException, this iterator contains no elements.
      Parameters:
      ignored - ignored.
      Throws:
      IllegalStateException - Always thrown.