Movatterモバイル変換

Interface NavigableMap<K,V>

Type Parameters:
K - the type of keys maintained by this map
V - the type of mapped values
All Superinterfaces:
Map<K,V>,SortedMap<K,V>
All Known Subinterfaces:
ConcurrentNavigableMap<K,V>
All Known Implementing Classes:
ConcurrentSkipListMap,TreeMap
```
public interfaceNavigableMap<K,V>extendsSortedMap<K,V>
```
ASortedMap extended with navigation methods returning the closest matches for given search targets. MethodslowerEntry(K),floorEntry(K),ceilingEntry(K), andhigherEntry(K) returnMap.Entry objects associated with keys respectively less than, less than or equal, greater than or equal, and greater than a given key, returningnull if there is no such key. Similarly, methodslowerKey(K),floorKey(K),ceilingKey(K), andhigherKey(K) return only the associated keys. All of these methods are designed for locating, not traversing entries.
ANavigableMap may be accessed and traversed in either ascending or descending key order. ThedescendingMap() method returns a view of the map with the senses of all relational and directional methods inverted. The performance of ascending operations and views is likely to be faster than that of descending ones. MethodssubMap(K, boolean, K, boolean),headMap(K, boolean), andtailMap(K, boolean) differ from the like-namedSortedMap methods in accepting additional arguments describing whether lower and upper bounds are inclusive versus exclusive. Submaps of anyNavigableMap must implement theNavigableMap interface.
This interface additionally defines methodsfirstEntry(),pollFirstEntry(),lastEntry(), andpollLastEntry() that return and/or remove the least and greatest mappings, if any exist, else returningnull.
Implementations of entry-returning methods are expected to returnMap.Entry pairs representing snapshots of mappings at the time they were produced, and thus generally donot support the optionalEntry.setValue method. Note however that it is possible to change mappings in the associated map using methodput.
MethodssubMap(K, K),headMap(K), andtailMap(K) are specified to returnSortedMap to allow existing implementations ofSortedMap to be compatibly retrofitted to implementNavigableMap, but extensions and implementations of this interface are encouraged to override these methods to returnNavigableMap. Similarly,SortedMap.keySet() can be overridden to returnNavigableSet.
This interface is a member of the Java Collections Framework.
Since:
1.6

Nested Class Summary
- Nested classes/interfaces declared in interface java.util.Map
  Map.Entry<K,V>

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Map.Entry<K,V>`	`ceilingEntry(K key)`	Returns a key-value mapping associated with the least key greater than or equal to the given key, or`null` if there is no such key.
`K`	`ceilingKey(K key)`	Returns the least key greater than or equal to the given key, or`null` if there is no such key.
`NavigableSet<K>`	`descendingKeySet()`	Returns a reverse order`NavigableSet` view of the keys contained in this map.
`NavigableMap<K,V>`	`descendingMap()`	Returns a reverse order view of the mappings contained in this map.
`Map.Entry<K,V>`	`firstEntry()`	Returns a key-value mapping associated with the least key in this map, or`null` if the map is empty.
`Map.Entry<K,V>`	`floorEntry(K key)`	Returns a key-value mapping associated with the greatest key less than or equal to the given key, or`null` if there is no such key.
`K`	`floorKey(K key)`	Returns the greatest key less than or equal to the given key, or`null` if there is no such key.
`SortedMap<K,V>`	`headMap(K toKey)`	Returns a view of the portion of this map whose keys are strictly less than`toKey`.
`NavigableMap<K,V>`	`headMap(K toKey, boolean inclusive)`	Returns a view of the portion of this map whose keys are less than (or equal to, if`inclusive` is true)`toKey`.
`Map.Entry<K,V>`	`higherEntry(K key)`	Returns a key-value mapping associated with the least key strictly greater than the given key, or`null` if there is no such key.
`K`	`higherKey(K key)`	Returns the least key strictly greater than the given key, or`null` if there is no such key.
`Map.Entry<K,V>`	`lastEntry()`	Returns a key-value mapping associated with the greatest key in this map, or`null` if the map is empty.
`Map.Entry<K,V>`	`lowerEntry(K key)`	Returns a key-value mapping associated with the greatest key strictly less than the given key, or`null` if there is no such key.
`K`	`lowerKey(K key)`	Returns the greatest key strictly less than the given key, or`null` if there is no such key.
`NavigableSet<K>`	`navigableKeySet()`	Returns a`NavigableSet` view of the keys contained in this map.
`Map.Entry<K,V>`	`pollFirstEntry()`	Removes and returns a key-value mapping associated with the least key in this map, or`null` if the map is empty.
`Map.Entry<K,V>`	`pollLastEntry()`	Removes and returns a key-value mapping associated with the greatest key in this map, or`null` if the map is empty.
`NavigableMap<K,V>`	`subMap(K fromKey, boolean fromInclusive,K toKey, boolean toInclusive)`	Returns a view of the portion of this map whose keys range from`fromKey` to`toKey`.
`SortedMap<K,V>`	`subMap(K fromKey,K toKey)`	Returns a view of the portion of this map whose keys range from`fromKey`, inclusive, to`toKey`, exclusive.
`SortedMap<K,V>`	`tailMap(K fromKey)`	Returns a view of the portion of this map whose keys are greater than or equal to`fromKey`.
`NavigableMap<K,V>`	`tailMap(K fromKey, boolean inclusive)`	Returns a view of the portion of this map whose keys are greater than (or equal to, if`inclusive` is true)`fromKey`.

Methods declared in interface java.util.Map
clear,compute,computeIfAbsent,computeIfPresent,containsKey,containsValue,equals,forEach,get,getOrDefault,hashCode,isEmpty,merge,put,putAll,putIfAbsent,remove,remove,replace,replace,replaceAll,size

Methods declared in interface java.util.SortedMap
comparator,entrySet,firstKey,keySet,lastKey,values

- Method Detail
  - lowerEntry
```
Map.Entry<K,V> lowerEntry(K key)
```
    Returns a key-value mapping associated with the greatest key strictly less than the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    an entry with the greatest key less thankey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - lowerKey
```
K lowerKey(K key)
```
    Returns the greatest key strictly less than the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    the greatest key less thankey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - floorEntry
```
Map.Entry<K,V> floorEntry(K key)
```
    Returns a key-value mapping associated with the greatest key less than or equal to the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    an entry with the greatest key less than or equal tokey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - floorKey
```
K floorKey(K key)
```
    Returns the greatest key less than or equal to the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    the greatest key less than or equal tokey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - ceilingEntry
```
Map.Entry<K,V> ceilingEntry(K key)
```
    Returns a key-value mapping associated with the least key greater than or equal to the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    an entry with the least key greater than or equal tokey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - ceilingKey
```
K ceilingKey(K key)
```
    Returns the least key greater than or equal to the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    the least key greater than or equal tokey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - higherEntry
```
Map.Entry<K,V> higherEntry(K key)
```
    Returns a key-value mapping associated with the least key strictly greater than the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    an entry with the least key greater thankey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - higherKey
```
K higherKey(K key)
```
    Returns the least key strictly greater than the given key, ornull if there is no such key.
    Parameters:
    key - the key
    Returns:
    the least key greater thankey, ornull if there is no such key
    Throws:
    ClassCastException - if the specified key cannot be compared with the keys currently in the map
    NullPointerException - if the specified key is null and this map does not permit null keys
  - firstEntry
```
Map.Entry<K,V> firstEntry()
```
    Returns a key-value mapping associated with the least key in this map, ornull if the map is empty.
    Returns:
    an entry with the least key, ornull if this map is empty
  - lastEntry
```
Map.Entry<K,V> lastEntry()
```
    Returns a key-value mapping associated with the greatest key in this map, ornull if the map is empty.
    Returns:
    an entry with the greatest key, ornull if this map is empty
  - pollFirstEntry
```
Map.Entry<K,V> pollFirstEntry()
```
    Removes and returns a key-value mapping associated with the least key in this map, ornull if the map is empty.
    Returns:
    the removed first entry of this map, ornull if this map is empty
  - pollLastEntry
```
Map.Entry<K,V> pollLastEntry()
```
    Removes and returns a key-value mapping associated with the greatest key in this map, ornull if the map is empty.
    Returns:
    the removed last entry of this map, ornull if this map is empty
  - descendingMap
```
NavigableMap<K,V> descendingMap()
```
    Returns a reverse order view of the mappings contained in this map. The descending map is backed by this map, so changes to the map are reflected in the descending map, and vice-versa. If either map is modified while an iteration over a collection view of either map is in progress (except through the iterator's ownremove operation), the results of the iteration are undefined.
    The returned map has an ordering equivalent toCollections.reverseOrder(comparator()). The expressionm.descendingMap().descendingMap() returns a view ofm essentially equivalent tom.
    Returns:
    a reverse order view of this map
  - navigableKeySet
```
NavigableSet<K> navigableKeySet()
```
    Returns aNavigableSet view of the keys contained in this map. The set's iterator returns the keys in ascending order. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclear operations. It does not support theadd oraddAll operations.
    Returns:
    a navigable set view of the keys in this map
  - descendingKeySet
```
NavigableSet<K> descendingKeySet()
```
    Returns a reverse orderNavigableSet view of the keys contained in this map. The set's iterator returns the keys in descending order. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via theIterator.remove,Set.remove,removeAll,retainAll, andclear operations. It does not support theadd oraddAll operations.
    Returns:
    a reverse order navigable set view of the keys in this map
  - subMap
```
NavigableMap<K,V> subMap(K fromKey,                               boolean fromInclusive,K toKey,                               boolean toInclusive)
```
    Returns a view of the portion of this map whose keys range fromfromKey totoKey. IffromKey andtoKey are equal, the returned map is empty unlessfromInclusive andtoInclusive are both true. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside of its range, or to construct a submap either of whose endpoints lie outside its range.
    Parameters:
    fromKey - low endpoint of the keys in the returned map
    fromInclusive -true if the low endpoint is to be included in the returned view
    toKey - high endpoint of the keys in the returned map
    toInclusive -true if the high endpoint is to be included in the returned view
    Returns:
    a view of the portion of this map whose keys range fromfromKey totoKey
    Throws:
    ClassCastException - iffromKey andtoKey cannot be compared to one another using this map's comparator (or, if the map has no comparator, using natural ordering). Implementations may, but are not required to, throw this exception iffromKey ortoKey cannot be compared to keys currently in the map.
    NullPointerException - iffromKey ortoKey is null and this map does not permit null keys
    IllegalArgumentException - iffromKey is greater thantoKey; or if this map itself has a restricted range, andfromKey ortoKey lies outside the bounds of the range
  - headMap
```
NavigableMap<K,V> headMap(K toKey,                                boolean inclusive)
```
    Returns a view of the portion of this map whose keys are less than (or equal to, ifinclusive is true)toKey. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside its range.
    Parameters:
    toKey - high endpoint of the keys in the returned map
    inclusive -true if the high endpoint is to be included in the returned view
    Returns:
    a view of the portion of this map whose keys are less than (or equal to, ifinclusive is true)toKey
    Throws:
    ClassCastException - iftoKey is not compatible with this map's comparator (or, if the map has no comparator, iftoKey does not implementComparable). Implementations may, but are not required to, throw this exception iftoKey cannot be compared to keys currently in the map.
    NullPointerException - iftoKey is null and this map does not permit null keys
    IllegalArgumentException - if this map itself has a restricted range, andtoKey lies outside the bounds of the range
  - tailMap
```
NavigableMap<K,V> tailMap(K fromKey,                                boolean inclusive)
```
    Returns a view of the portion of this map whose keys are greater than (or equal to, ifinclusive is true)fromKey. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside its range.
    Parameters:
    fromKey - low endpoint of the keys in the returned map
    inclusive -true if the low endpoint is to be included in the returned view
    Returns:
    a view of the portion of this map whose keys are greater than (or equal to, ifinclusive is true)fromKey
    Throws:
    ClassCastException - iffromKey is not compatible with this map's comparator (or, if the map has no comparator, iffromKey does not implementComparable). Implementations may, but are not required to, throw this exception iffromKey cannot be compared to keys currently in the map.
    NullPointerException - iffromKey is null and this map does not permit null keys
    IllegalArgumentException - if this map itself has a restricted range, andfromKey lies outside the bounds of the range
  - subMap
```
SortedMap<K,V> subMap(K fromKey,K toKey)
```
    Returns a view of the portion of this map whose keys range fromfromKey, inclusive, totoKey, exclusive. (IffromKey andtoKey are equal, the returned map is empty.) The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside its range.
    Equivalent tosubMap(fromKey, true, toKey, false).
    Specified by:
    subMap in interface SortedMap<K,V>
    Parameters:
    fromKey - low endpoint (inclusive) of the keys in the returned map
    toKey - high endpoint (exclusive) of the keys in the returned map
    Returns:
    a view of the portion of this map whose keys range fromfromKey, inclusive, totoKey, exclusive
    Throws:
    ClassCastException - iffromKey andtoKey cannot be compared to one another using this map's comparator (or, if the map has no comparator, using natural ordering). Implementations may, but are not required to, throw this exception iffromKey ortoKey cannot be compared to keys currently in the map.
    NullPointerException - iffromKey ortoKey is null and this map does not permit null keys
    IllegalArgumentException - iffromKey is greater thantoKey; or if this map itself has a restricted range, andfromKey ortoKey lies outside the bounds of the range
  - headMap
```
SortedMap<K,V> headMap(K toKey)
```
    Returns a view of the portion of this map whose keys are strictly less thantoKey. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside its range.
    Equivalent toheadMap(toKey, false).
    Specified by:
    headMap in interface SortedMap<K,V>
    Parameters:
    toKey - high endpoint (exclusive) of the keys in the returned map
    Returns:
    a view of the portion of this map whose keys are strictly less thantoKey
    Throws:
    ClassCastException - iftoKey is not compatible with this map's comparator (or, if the map has no comparator, iftoKey does not implementComparable). Implementations may, but are not required to, throw this exception iftoKey cannot be compared to keys currently in the map.
    NullPointerException - iftoKey is null and this map does not permit null keys
    IllegalArgumentException - if this map itself has a restricted range, andtoKey lies outside the bounds of the range
  - tailMap
```
SortedMap<K,V> tailMap(K fromKey)
```
    Returns a view of the portion of this map whose keys are greater than or equal tofromKey. The returned map is backed by this map, so changes in the returned map are reflected in this map, and vice-versa. The returned map supports all optional map operations that this map supports.
    The returned map will throw anIllegalArgumentException on an attempt to insert a key outside its range.
    Equivalent totailMap(fromKey, true).
    Specified by:
    tailMap in interface SortedMap<K,V>
    Parameters:
    fromKey - low endpoint (inclusive) of the keys in the returned map
    Returns:
    a view of the portion of this map whose keys are greater than or equal tofromKey
    Throws:
    ClassCastException - iffromKey is not compatible with this map's comparator (or, if the map has no comparator, iffromKey does not implementComparable). Implementations may, but are not required to, throw this exception iffromKey cannot be compared to keys currently in the map.
    NullPointerException - iffromKey is null and this map does not permit null keys
    IllegalArgumentException - if this map itself has a restricted range, andfromKey lies outside the bounds of the range

Movatterモバイル変換

Interface NavigableMap<K,​V>

Nested Class Summary

Nested classes/interfaces declared in interface java.util.Map

Method Summary

Methods declared in interface java.util.Map

Methods declared in interface java.util.SortedMap

Method Detail

lowerEntry

lowerKey

floorEntry

floorKey

ceilingEntry

ceilingKey

higherEntry

higherKey

firstEntry

lastEntry

pollFirstEntry

pollLastEntry

descendingMap

navigableKeySet

descendingKeySet

subMap

headMap

tailMap

subMap

headMap

tailMap

Interface NavigableMap<K,V>