ConcurrentSkipListMap (Java Platform SE 6) (original) (raw)
java.util.concurrent
Class ConcurrentSkipListMap<K,V>
java.lang.Object
java.util.AbstractMap<K,V>
java.util.concurrent.ConcurrentSkipListMap<K,V>
Type Parameters:
K - the type of keys maintained by this map
V - the type of mapped values
All Implemented Interfaces:
Serializable, Cloneable, ConcurrentMap<K,V>, ConcurrentNavigableMap<K,V>, Map<K,V>, NavigableMap<K,V>, SortedMap<K,V>
public class ConcurrentSkipListMap<K,V>
extends AbstractMap<K,V>
implements ConcurrentNavigableMap<K,V>, Cloneable, Serializable
A scalable concurrent ConcurrentNavigableMap implementation. The map is sorted according to the natural ordering of its keys, or by a Comparator provided at map creation time, depending on which constructor is used.
This class implements a concurrent variant of SkipLists providing expected average log(n) time cost for thecontainsKey, get, put andremove operations and their variants. Insertion, removal, update, and access operations safely execute concurrently by multiple threads. Iterators are weakly consistent, returning elements reflecting the state of the map at some point at or since the creation of the iterator. They do not throw ConcurrentModificationException, and may proceed concurrently with other operations. Ascending key ordered views and their iterators are faster than descending ones.
All Map.Entry pairs returned by methods in this class and its views represent snapshots of mappings at the time they were produced. They do not support the Entry.setValue method. (Note however that it is possible to change mappings in the associated map using put, putIfAbsent, orreplace, depending on exactly which effect you need.)
Beware that, unlike in most collections, the size method is not a constant-time operation. Because of the asynchronous nature of these maps, determining the current number of elements requires a traversal of the elements. Additionally, the bulk operations putAll, equals, andclear are not guaranteed to be performed atomically. For example, an iterator operating concurrently with aputAll operation might view only some of the added elements.
This class and its views and iterators implement all of the_optional_ methods of the Map and Iterator interfaces. Like most other concurrent collections, this class does_not_ permit the use of null keys or values because some null return values cannot be reliably distinguished from the absence of elements.
This class is a member of the Java Collections Framework.
Since:
1.6
See Also:
| Nested Class Summary |
|---|
| Nested classes/interfaces inherited from class java.util.AbstractMap |
|---|
| AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V> |
| Nested classes/interfaces inherited from interface java.util.Map |
|---|
| Map.Entry<K,V> |
| Constructor Summary |
|---|
| ConcurrentSkipListMap() Constructs a new, empty map, sorted according to thenatural ordering of the keys. |
| ConcurrentSkipListMap(Comparator<? super K> comparator) Constructs a new, empty map, sorted according to the specified comparator. |
| ConcurrentSkipListMap(Map<? extends K,? extends V> m) Constructs a new map containing the same mappings as the given map, sorted according to the natural ordering of the keys. |
| ConcurrentSkipListMap(SortedMap<K,? extends V> m) Constructs a new map containing the same mappings and using the same ordering as the specified sorted map. |
| Method Summary | |
|---|---|
| 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 entry. |
| K | ceilingKey(K key) Returns the least key greater than or equal to the given key, or null if there is no such key. |
| void | clear() Removes all of the mappings from this map. |
| ConcurrentSkipListMap<K,V> | clone() Returns a shallow copy of this ConcurrentSkipListMap instance. |
| Comparator<? super K> | comparator() Returns the comparator used to order the keys in this map, ornull if this map uses the natural ordering of its keys. |
| boolean | containsKey(Object key) Returns true if this map contains a mapping for the specified key. |
| boolean | containsValue(Object value) Returns true if this map maps one or more keys to the specified value. |
| NavigableSet<K> | descendingKeySet() Returns a reverse order NavigableSet view of the keys contained in this map. |
| ConcurrentNavigableMap<K,V> | descendingMap() Returns a reverse order view of the mappings contained in this map. |
| Set<Map.Entry<K,V>> | entrySet() Returns a Set view of the mappings contained in this map. |
| boolean | equals(Object o) Compares the specified object with this map for equality. |
| 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. |
| K | firstKey() Returns the first (lowest) key currently in this map. |
| 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. |
| V | get(Object key) Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key. |
| ConcurrentNavigableMap<K,V> | headMap(K toKey) Returns a view of the portion of this map whose keys are strictly less than toKey. |
| ConcurrentNavigableMap<K,V> | [headMap](../../../java/util/concurrent/ConcurrentSkipListMap.html#headMap%28K, boolean%29)(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, ornull if there is no such key. |
| boolean | isEmpty() Returns true if this map contains no key-value mappings. |
| NavigableSet<K> | keySet() Returns a NavigableSet view of the keys contained in this map. |
| 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. |
| K | lastKey() Returns the last (highest) key currently in this map. |
| 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, ornull 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. |
| V | [put](../../../java/util/concurrent/ConcurrentSkipListMap.html#put%28K, V%29)(K key,V value) Associates the specified value with the specified key in this map. |
| V | [putIfAbsent](../../../java/util/concurrent/ConcurrentSkipListMap.html#putIfAbsent%28K, V%29)(K key,V value) If the specified key is not already associated with a value, associate it with the given value. |
| V | remove(Object key) Removes the mapping for the specified key from this map if present. |
| boolean | [remove](../../../java/util/concurrent/ConcurrentSkipListMap.html#remove%28java.lang.Object, java.lang.Object%29)(Object key,Object value) Removes the entry for a key only if currently mapped to a given value. |
| V | [replace](../../../java/util/concurrent/ConcurrentSkipListMap.html#replace%28K, V%29)(K key,V value) Replaces the entry for a key only if currently mapped to some value. |
| boolean | [replace](../../../java/util/concurrent/ConcurrentSkipListMap.html#replace%28K, V, V%29)(K key,V oldValue,V newValue) Replaces the entry for a key only if currently mapped to a given value. |
| int | size() Returns the number of key-value mappings in this map. |
| ConcurrentNavigableMap<K,V> | [subMap](../../../java/util/concurrent/ConcurrentSkipListMap.html#subMap%28K, boolean, K, boolean%29)(K fromKey, boolean fromInclusive,K toKey, boolean toInclusive) Returns a view of the portion of this map whose keys range fromfromKey to toKey. |
| ConcurrentNavigableMap<K,V> | [subMap](../../../java/util/concurrent/ConcurrentSkipListMap.html#subMap%28K, K%29)(K fromKey,K toKey) Returns a view of the portion of this map whose keys range fromfromKey, inclusive, to toKey, exclusive. |
| ConcurrentNavigableMap<K,V> | tailMap(K fromKey) Returns a view of the portion of this map whose keys are greater than or equal to fromKey. |
| ConcurrentNavigableMap<K,V> | [tailMap](../../../java/util/concurrent/ConcurrentSkipListMap.html#tailMap%28K, boolean%29)(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. |
| Collection<V> | values() Returns a Collection view of the values contained in this map. |
| Methods inherited from class java.util.AbstractMap |
|---|
| hashCode, putAll, toString |
| Methods inherited from class java.lang.Object |
|---|
| finalize, getClass, notify, notifyAll, wait, wait, [wait](../../../java/lang/Object.html#wait%28long, int%29) |
| Methods inherited from interface java.util.Map |
|---|
| hashCode, putAll |
| Constructor Detail |
|---|
ConcurrentSkipListMap
public ConcurrentSkipListMap()
Constructs a new, empty map, sorted according to thenatural ordering of the keys.
ConcurrentSkipListMap
public ConcurrentSkipListMap(Comparator<? super K> comparator)
Constructs a new, empty map, sorted according to the specified comparator.
Parameters:
comparator - the comparator that will be used to order this map. If null, the natural ordering of the keys will be used.
ConcurrentSkipListMap
public ConcurrentSkipListMap(Map<? extends K,? extends V> m)
Constructs a new map containing the same mappings as the given map, sorted according to the natural ordering of the keys.
Parameters:
m - the map whose mappings are to be placed in this map
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the keys in m are notComparable, or are not mutually comparable
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified map or any of its keys or values are null
ConcurrentSkipListMap
public ConcurrentSkipListMap(SortedMap<K,? extends V> m)
Constructs a new map containing the same mappings and using the same ordering as the specified sorted map.
Parameters:
m - the sorted map whose mappings are to be placed in this map, and whose comparator is to be used to sort this map
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified sorted map or any of its keys or values are null
| Method Detail |
|---|
clone
public ConcurrentSkipListMap<K,V> clone()
Returns a shallow copy of this ConcurrentSkipListMap instance. (The keys and values themselves are not cloned.)
Overrides:
[clone](../../../java/util/AbstractMap.html#clone%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a shallow copy of this map
See Also:
containsKey
public boolean containsKey(Object key)
Returns true if this map contains a mapping for the specified key.
Specified by:
[containsKey](../../../java/util/Map.html#containsKey%28java.lang.Object%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[containsKey](../../../java/util/AbstractMap.html#containsKey%28java.lang.Object%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key whose presence in this map is to be tested
Returns:
true if this map contains a mapping for the specified key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
get
Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
More formally, if this map contains a mapping from a keyk to a value v such that key compares equal to k according to the map's ordering, then this method returns v; otherwise it returns null. (There can be at most one such mapping.)
Specified by:
[get](../../../java/util/Map.html#get%28java.lang.Object%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[get](../../../java/util/AbstractMap.html#get%28java.lang.Object%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key whose associated value is to be returned
Returns:
the value to which the specified key is mapped, ornull if this map contains no mapping for the key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
put
Associates the specified value with the specified key in this map. If the map previously contained a mapping for the key, the old value is replaced.
Specified by:
[put](../../../java/util/Map.html#put%28K, V%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[put](../../../java/util/AbstractMap.html#put%28K, V%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key with which the specified value is to be associated
value - value to be associated with the specified key
Returns:
the previous value associated with the specified key, ornull if there was no mapping for the key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key or value is null
remove
Removes the mapping for the specified key from this map if present.
Specified by:
[remove](../../../java/util/Map.html#remove%28java.lang.Object%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[remove](../../../java/util/AbstractMap.html#remove%28java.lang.Object%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key for which mapping should be removed
Returns:
the previous value associated with the specified key, ornull if there was no mapping for the key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
containsValue
public boolean containsValue(Object value)
Returns true if this map maps one or more keys to the specified value. This operation requires time linear in the map size.
Specified by:
[containsValue](../../../java/util/Map.html#containsValue%28java.lang.Object%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[containsValue](../../../java/util/AbstractMap.html#containsValue%28java.lang.Object%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
value - value whose presence in this map is to be tested
Returns:
true if a mapping to value exists;false otherwise
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified value is null
size
public int size()
Returns the number of key-value mappings in this map. If this map contains more than Integer.MAX_VALUE elements, it returns Integer.MAX_VALUE.
Beware that, unlike in most collections, this method is_NOT_ a constant-time operation. Because of the asynchronous nature of these maps, determining the current number of elements requires traversing them all to count them. Additionally, it is possible for the size to change during execution of this method, in which case the returned result will be inaccurate. Thus, this method is typically not very useful in concurrent applications.
Specified by:
[size](../../../java/util/Map.html#size%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[size](../../../java/util/AbstractMap.html#size%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the number of elements in this map
isEmpty
public boolean isEmpty()
Returns true if this map contains no key-value mappings.
Specified by:
[isEmpty](../../../java/util/Map.html#isEmpty%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[isEmpty](../../../java/util/AbstractMap.html#isEmpty%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
true if this map contains no key-value mappings
clear
public void clear()
Removes all of the mappings from this map.
Specified by:
[clear](../../../java/util/Map.html#clear%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[clear](../../../java/util/AbstractMap.html#clear%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
keySet
public NavigableSet<K> keySet()
Returns a NavigableSet 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. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove,removeAll, retainAll, and clear operations. It does not support the add or addAll operations.
The view's iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.
This method is equivalent to method navigableKeySet.
Specified by:
[keySet](../../../java/util/concurrent/ConcurrentNavigableMap.html#keySet%28%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[keySet](../../../java/util/Map.html#keySet%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[keySet](../../../java/util/SortedMap.html#keySet%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[keySet](../../../java/util/AbstractMap.html#keySet%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a navigable set view of the keys in this map
navigableKeySet
public NavigableSet<K> navigableKeySet()
Description copied from interface: [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#navigableKeySet%28%29)
Returns a NavigableSet 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. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove,removeAll, retainAll, and clear operations. It does not support the add or addAll operations.
The view's iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.
Specified by:
[navigableKeySet](../../../java/util/concurrent/ConcurrentNavigableMap.html#navigableKeySet%28%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[navigableKeySet](../../../java/util/NavigableMap.html#navigableKeySet%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a navigable set view of the keys in this map
values
public Collection<V> values()
Returns a Collection view of the values contained in this map. The collection's iterator returns the values in ascending order of the corresponding keys. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove,Collection.remove, removeAll,retainAll and clear operations. It does not support the add or addAll operations.
The view's iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.
Specified by:
[values](../../../java/util/Map.html#values%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[values](../../../java/util/SortedMap.html#values%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[values](../../../java/util/AbstractMap.html#values%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a collection view of the values contained in this map
entrySet
public Set<Map.Entry<K,V>> entrySet()
Returns a Set view of the mappings contained in this map. The set's iterator returns the entries in ascending key order. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove,removeAll, retainAll and clear operations. It does not support the add oraddAll operations.
The view's iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.
The Map.Entry elements returned byiterator.next() do not support thesetValue operation.
Specified by:
[entrySet](../../../java/util/Map.html#entrySet%28%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[entrySet](../../../java/util/SortedMap.html#entrySet%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[entrySet](../../../java/util/AbstractMap.html#entrySet%28%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a set view of the mappings contained in this map, sorted in ascending key order
descendingMap
public ConcurrentNavigableMap<K,V> descendingMap()
Description copied from interface: [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#descendingMap%28%29)
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.
The returned map has an ordering equivalent toCollections.reverseOrder(comparator()). The expression m.descendingMap().descendingMap() returns a view of m essentially equivalent to m.
Specified by:
[descendingMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#descendingMap%28%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[descendingMap](../../../java/util/NavigableMap.html#descendingMap%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a reverse order view of this map
descendingKeySet
public NavigableSet<K> descendingKeySet()
Description copied from interface: [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#descendingKeySet%28%29)
Returns a reverse order NavigableSet 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. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove,removeAll, retainAll, and clear operations. It does not support the add or addAll operations.
The view's iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.
Specified by:
[descendingKeySet](../../../java/util/concurrent/ConcurrentNavigableMap.html#descendingKeySet%28%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[descendingKeySet](../../../java/util/NavigableMap.html#descendingKeySet%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
a reverse order navigable set view of the keys in this map
equals
public boolean equals(Object o)
Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings. More formally, two mapsm1 and m2 represent the same mappings ifm1.entrySet().equals(m2.entrySet()). This operation may return misleading results if either map is concurrently modified during execution of this method.
Specified by:
[equals](../../../java/util/Map.html#equals%28java.lang.Object%29) in interface [Map](../../../java/util/Map.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Overrides:
[equals](../../../java/util/AbstractMap.html#equals%28java.lang.Object%29) in class [AbstractMap](../../../java/util/AbstractMap.html "class in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
o - object to be compared for equality with this map
Returns:
true if the specified object is equal to this map
See Also:
putIfAbsent
public V putIfAbsent(K key, V value)
If the specified key is not already associated with a value, associate it with the given value. This is equivalent to
if (!map.containsKey(key)) return map.put(key, value); else return map.get(key);
except that the action is performed atomically.
Specified by:
[putIfAbsent](../../../java/util/concurrent/ConcurrentMap.html#putIfAbsent%28K, V%29) in interface [ConcurrentMap](../../../java/util/concurrent/ConcurrentMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key with which the specified value is to be associated
value - value to be associated with the specified key
Returns:
the previous value associated with the specified key, or null if there was no mapping for the key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key or value is null
remove
public boolean remove(Object key, Object value)
Removes the entry for a key only if currently mapped to a given value. This is equivalent to
if (map.containsKey(key) && map.get(key).equals(value)) { map.remove(key); return true; } else return false;
except that the action is performed atomically.
Specified by:
[remove](../../../java/util/concurrent/ConcurrentMap.html#remove%28java.lang.Object, java.lang.Object%29) in interface [ConcurrentMap](../../../java/util/concurrent/ConcurrentMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key with which the specified value is associated
value - value expected to be associated with the specified key
Returns:
true if the value was removed
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
replace
public boolean replace(K key, V oldValue, V newValue)
Replaces the entry for a key only if currently mapped to a given value. This is equivalent to
if (map.containsKey(key) && map.get(key).equals(oldValue)) { map.put(key, newValue); return true; } else return false;
except that the action is performed atomically.
Specified by:
[replace](../../../java/util/concurrent/ConcurrentMap.html#replace%28K, V, V%29) in interface [ConcurrentMap](../../../java/util/concurrent/ConcurrentMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key with which the specified value is associated
oldValue - value expected to be associated with the specified key
newValue - value to be associated with the specified key
Returns:
true if the value was replaced
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if any of the arguments are null
replace
public V replace(K key, V value)
Replaces the entry for a key only if currently mapped to some value. This is equivalent to
if (map.containsKey(key)) { return map.put(key, value); } else return null;
except that the action is performed atomically.
Specified by:
[replace](../../../java/util/concurrent/ConcurrentMap.html#replace%28K, V%29) in interface [ConcurrentMap](../../../java/util/concurrent/ConcurrentMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - key with which the specified value is associated
value - value to be associated with the specified key
Returns:
the previous value associated with the specified key, or null if there was no mapping for the key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key or value is null
comparator
public Comparator<? super K> comparator()
Description copied from interface: [SortedMap](../../../java/util/SortedMap.html#comparator%28%29)
Returns the comparator used to order the keys in this map, ornull if this map uses the natural ordering of its keys.
Specified by:
[comparator](../../../java/util/SortedMap.html#comparator%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the comparator used to order the keys in this map, or null if this map uses the natural ordering of its keys
firstKey
public K firstKey()
Description copied from interface: [SortedMap](../../../java/util/SortedMap.html#firstKey%28%29)
Returns the first (lowest) key currently in this map.
Specified by:
[firstKey](../../../java/util/SortedMap.html#firstKey%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the first (lowest) key currently in this map
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this map is empty
lastKey
public K lastKey()
Description copied from interface: [SortedMap](../../../java/util/SortedMap.html#lastKey%28%29)
Returns the last (highest) key currently in this map.
Specified by:
[lastKey](../../../java/util/SortedMap.html#lastKey%28%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the last (highest) key currently in this map
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this map is empty
subMap
public ConcurrentNavigableMap<K,V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#subMap%28K, boolean, K, boolean%29)
Returns a view of the portion of this map whose keys range fromfromKey to toKey. If fromKey andtoKey are equal, the returned map is empty unlessfromExclusive and toExclusive 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 an IllegalArgumentException on an attempt to insert a key outside of its range, or to construct a submap either of whose endpoints lie outside its range.
Specified by:
[subMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#subMap%28K, boolean, K, boolean%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[subMap](../../../java/util/NavigableMap.html#subMap%28K, boolean, K, boolean%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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 to toKey
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if fromKey and toKey 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 if fromKey or toKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if fromKey or toKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if fromKey is greater thantoKey; or if this map itself has a restricted range, and fromKey or toKey lies outside the bounds of the range
headMap
public ConcurrentNavigableMap<K,V> headMap(K toKey, boolean inclusive)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#headMap%28K, boolean%29)
Returns a view of the portion of this map whose keys are less than (or equal to, if inclusive 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 an IllegalArgumentException on an attempt to insert a key outside its range.
Specified by:
[headMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#headMap%28K, boolean%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[headMap](../../../java/util/NavigableMap.html#headMap%28K, boolean%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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, if inclusive is true) toKey
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if toKey is not compatible with this map's comparator (or, if the map has no comparator, if toKey does not implement Comparable). Implementations may, but are not required to, throw this exception if toKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if toKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if this map itself has a restricted range, and toKey lies outside the bounds of the range
tailMap
public ConcurrentNavigableMap<K,V> tailMap(K fromKey, boolean inclusive)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#tailMap%28K, boolean%29)
Returns a view of the portion of this map whose keys are greater than (or equal to, if inclusive 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 an IllegalArgumentException on an attempt to insert a key outside its range.
Specified by:
[tailMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#tailMap%28K, boolean%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[tailMap](../../../java/util/NavigableMap.html#tailMap%28K, boolean%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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, if inclusive is true) fromKey
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if fromKey is not compatible with this map's comparator (or, if the map has no comparator, if fromKey does not implement Comparable). Implementations may, but are not required to, throw this exception if fromKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if fromKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if this map itself has a restricted range, and fromKey lies outside the bounds of the range
subMap
public ConcurrentNavigableMap<K,V> subMap(K fromKey, K toKey)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#subMap%28K, K%29)
Returns a view of the portion of this map whose keys range fromfromKey, inclusive, to toKey, exclusive. (IffromKey and toKey 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 an IllegalArgumentException on an attempt to insert a key outside its range.
Equivalent to subMap(fromKey, true, toKey, false).
Specified by:
[subMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#subMap%28K, K%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[subMap](../../../java/util/NavigableMap.html#subMap%28K, K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[subMap](../../../java/util/SortedMap.html#subMap%28K, K%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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, to toKey, exclusive
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if fromKey and toKey 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 if fromKey or toKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if fromKey or toKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if fromKey is greater thantoKey; or if this map itself has a restricted range, and fromKey or toKey lies outside the bounds of the range
headMap
public ConcurrentNavigableMap<K,V> headMap(K toKey)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#headMap%28K%29)
Returns a view of the portion of this map whose keys are strictly less than 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 an IllegalArgumentException on an attempt to insert a key outside its range.
Equivalent to headMap(toKey, false).
Specified by:
[headMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#headMap%28K%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[headMap](../../../java/util/NavigableMap.html#headMap%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[headMap](../../../java/util/SortedMap.html#headMap%28K%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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 than toKey
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if toKey is not compatible with this map's comparator (or, if the map has no comparator, if toKey does not implement Comparable). Implementations may, but are not required to, throw this exception if toKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if toKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if this map itself has a restricted range, and toKey lies outside the bounds of the range
tailMap
public ConcurrentNavigableMap<K,V> tailMap(K fromKey)
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#tailMap%28K%29)
Returns a view of the portion of this map whose keys are greater than or equal to 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 an IllegalArgumentException on an attempt to insert a key outside its range.
Equivalent to tailMap(fromKey, true).
Specified by:
[tailMap](../../../java/util/concurrent/ConcurrentNavigableMap.html#tailMap%28K%29) in interface [ConcurrentNavigableMap](../../../java/util/concurrent/ConcurrentNavigableMap.html "interface in java.util.concurrent")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[tailMap](../../../java/util/NavigableMap.html#tailMap%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Specified by:
[tailMap](../../../java/util/SortedMap.html#tailMap%28K%29) in interface [SortedMap](../../../java/util/SortedMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
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 to fromKey
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if fromKey is not compatible with this map's comparator (or, if the map has no comparator, if fromKey does not implement Comparable). Implementations may, but are not required to, throw this exception if fromKey cannot be compared to keys currently in the map.
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if fromKey is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if this map itself has a restricted range, and fromKey lies outside the bounds of the range
lowerEntry
public 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. The returned entry does not support theEntry.setValue method.
Specified by:
[lowerEntry](../../../java/util/NavigableMap.html#lowerEntry%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
an entry with the greatest key less than key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
lowerKey
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#lowerKey%28K%29)
Returns the greatest key strictly less than the given key, ornull if there is no such key.
Specified by:
[lowerKey](../../../java/util/NavigableMap.html#lowerKey%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
the greatest key less than key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
floorEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[floorEntry](../../../java/util/NavigableMap.html#floorEntry%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
an entry with the greatest key less than or equal tokey, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
floorKey
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#floorKey%28K%29)
Returns the greatest key less than or equal to the given key, or null if there is no such key.
Specified by:
[floorKey](../../../java/util/NavigableMap.html#floorKey%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
the greatest key less than or equal to key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
ceilingEntry
public 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 entry. The returned entry does not support the Entry.setValue method.
Specified by:
[ceilingEntry](../../../java/util/NavigableMap.html#ceilingEntry%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
an entry with the least key greater than or equal tokey, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
ceilingKey
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#ceilingKey%28K%29)
Returns the least key greater than or equal to the given key, or null if there is no such key.
Specified by:
[ceilingKey](../../../java/util/NavigableMap.html#ceilingKey%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
the least key greater than or equal to key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
higherEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[higherEntry](../../../java/util/NavigableMap.html#higherEntry%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
an entry with the least key greater than key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
higherKey
Description copied from interface: [NavigableMap](../../../java/util/NavigableMap.html#higherKey%28K%29)
Returns the least key strictly greater than the given key, ornull if there is no such key.
Specified by:
[higherKey](../../../java/util/NavigableMap.html#higherKey%28K%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Parameters:
key - the key
Returns:
the least key greater than key, or null if there is no such key
Throws:
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the specified key cannot be compared with the keys currently in the map
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified key is null
firstEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[firstEntry](../../../java/util/NavigableMap.html#firstEntry%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
an entry with the least key, or null if this map is empty
lastEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[lastEntry](../../../java/util/NavigableMap.html#lastEntry%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
an entry with the greatest key, or null if this map is empty
pollFirstEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[pollFirstEntry](../../../java/util/NavigableMap.html#pollFirstEntry%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the removed first entry of this map, or null if this map is empty
pollLastEntry
public 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. The returned entry does not support the Entry.setValue method.
Specified by:
[pollLastEntry](../../../java/util/NavigableMap.html#pollLastEntry%28%29) in interface [NavigableMap](../../../java/util/NavigableMap.html "interface in java.util")<[K](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap"),[V](../../../java/util/concurrent/ConcurrentSkipListMap.html "type parameter in ConcurrentSkipListMap")>
Returns:
the removed last entry of this map, or null if this map is empty
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