Interface NavigableMap<K,V>

Type Parameters:
K - the type of key
V - the type of value
All Superinterfaces:
Map<K,V>, SortedMap<K,V>
All Known Implementing Classes:
TreeMap

public interface NavigableMap<K,V> extends SortedMap<K,V>
NavigableMap is a SortedMap with navigation methods answering the closest matches for specified item.
Since:
1.6
  • Method Details

    • firstEntry

      Map.Entry<K,V> firstEntry()
      Answers the entry with the smallest key, or null if the map is empty.
      Returns:
      the entry with the smallest key, or null if the map is empty
    • lastEntry

      Map.Entry<K,V> lastEntry()
      Answers the entry with the biggest key, or null if the map is empty.
      Returns:
      the entry with the biggest key, or null if the map is empty
    • pollFirstEntry

      Map.Entry<K,V> pollFirstEntry()
      Deletes and answers the entry with the smallest key, or null if the map is empty.
      Returns:
      the entry with the smallest key, or null if the map is empty
    • pollLastEntry

      Map.Entry<K,V> pollLastEntry()
      Deletes and answers the entry with the biggest key, or null if the map is empty.
      Returns:
      the entry with the biggest key, or null if the map is empty
    • ceilingEntry

      Map.Entry<K,V> ceilingEntry(K key)
      Answers an entry related with the smallest key greater than or equal to the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the entry, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • ceilingKey

      K ceilingKey(K key)
      Answers the smallest key greater than or equal to the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the smallest key greater than or equal to key, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • higherEntry

      Map.Entry<K,V> higherEntry(K key)
      Answers an entry related with the smallest key greater than the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the entry, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • higherKey

      K higherKey(K key)
      Answers the smallest key greater than the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the smallest key greater than key, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • floorEntry

      Map.Entry<K,V> floorEntry(K key)
      Answers an entry related with the biggest key less than or equal to the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the entry, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • floorKey

      K floorKey(K key)
      Answers the biggest key less than or equal to the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the biggest key less than or equal to key, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • lowerEntry

      Map.Entry<K,V> lowerEntry(K key)
      Answers an entry related with the biggest key less than the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the entry, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • lowerKey

      K lowerKey(K key)
      Answers the biggest key less than the specified key, or null if no such key.
      Parameters:
      key - the key
      Returns:
      the biggest key less than key, or null if no such key
      Throws:
      ClassCastException - if the key cannot be compared with the keys in the map
      NullPointerException - if the key is null and the map can not contain null key
    • descendingMap

      NavigableMap<K,V> descendingMap()
      Answers a reverse order view of the map.
      Returns:
      the reverse order view of the map
    • descendingKeySet

      NavigableSet<K> descendingKeySet()
      Answers a NavigableSet view of the keys in descending order.
      Returns:
      the navigable set view
    • subMap

      NavigableMap<K,V> subMap(K startKey, boolean startInclusive, K endKey, boolean endInclusive)
      Answers a view of part of the map whose keys is from startKey to endKey.
      Parameters:
      startKey - the start key
      startInclusive - true if the start key is in the returned map
      endKey - the end key
      endInclusive - true if the end key is in the returned map
      Returns:
      the sub-map view
      Throws:
      ClassCastException - when the class of the start or end key is inappropriate for this SubMap
      NullPointerException - when the start or end key is null and this SortedMap does not support null keys
      IllegalArgumentException - when the start key is greater than the end key
    • headMap

      NavigableMap<K,V> headMap(K endKey, boolean inclusive)
      Answers a view of the head of the map whose keys are smaller than (or equal to, depends on inclusive argument) endKey.
      Parameters:
      endKey - the end key
      inclusive - true if the end key is in the returned map
      Returns:
      the head-map view
      Throws:
      ClassCastException - when the class of the end key is inappropriate for this SubMap
      NullPointerException - when the end key is null and this SortedMap does not support null keys
      IllegalArgumentException - when the map is range-limited and end key is out of the range of the map
    • tailMap

      NavigableMap<K,V> tailMap(K startKey, boolean inclusive)
      Answers a view of the tail of the map whose keys are bigger than (or equal to, depends on inclusive argument) startKey.
      Parameters:
      startKey - the start key
      inclusive - true if the start key is in the returned map
      Returns:
      the tail-map view
      Throws:
      ClassCastException - when the class of the start key is inappropriate for this SubMap
      NullPointerException - when the start key is null and this SortedMap does not support null keys
      IllegalArgumentException - when the map is range-limited and start key is out of the range of the map