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Summary: Ctors | Methods | Inherited Methods | [Expand All]

Added in API level 1

public class

TreeMap

extends AbstractMap <K, V>
implements Serializable Cloneable NavigableMap <K, V> SortedMap <K, V>

java.lang.Object
↳	java.util.AbstractMap <K, V>
	↳	java.util.TreeMap<K, V>

Class Overview

A map whose entries are sorted by their keys. All optional operations such as put(K, V) and remove(Object) are supported.

This map sorts keys using either a user-supplied comparator or the key's natural order:

User supplied comparators must be able to compare any pair of keys in this map. If a user-supplied comparator is in use, it will be returned by comparator() .
If no user-supplied comparator is supplied, keys will be sorted by their natural order. Keys must be mutually comparable : they must implement Comparable and compareTo() must be able to compare each key with any other key in this map. In this case comparator() will return null.

With either a comparator or a natural ordering, comparisons should be consistent with equals . An ordering is consistent with equals if for every pair of keys

and


        a.equals(b)

if and only if


        compare(a, b) == 0

When the ordering is not consistent with equals the behavior of this class is well defined but does not honor the contract specified by Map . Consider a tree map of case-insensitive strings, an ordering that is not consistent with equals:

        
         TreeMap
         
          map = new TreeMap
         
         
          (String.CASE_INSENSITIVE_ORDER);
   map.put("a", "android");

   // The Map API specifies that the next line should print "null" because
   // "a".equals("A") is false and there is no mapping for upper case "A".
   // But the case insensitive ordering says compare("a", "A") == 0. TreeMap
   // uses only comparators/comparable on keys and so this prints "android".
   System.out.println(map.get("A"));

Summary

Public Constructors
	TreeMap () Create a natural order, empty tree map whose keys must be mutually comparable and non-null.
	)">TreeMap ( Map <? extends K, ? extends V> copyFrom) Create a natural order tree map populated with the key/value pairs of `copyFrom` .
	)">TreeMap ( Comparator <? super K> comparator) Create a tree map ordered by `comparator` .
	)">TreeMap ( SortedMap <K, ? extends V> copyFrom) Create a tree map with the ordering and key/value pairs of `copyFrom` .

Public Methods
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.
void	clear () Removes all elements from this `Map` , leaving it empty. This implementation calls `entrySet().clear()` .
Object	clone () Creates and returns a copy of this `Object` .
Comparator <? super K>	comparator () Returns the comparator used to compare keys in this sorted map, or null if the natural ordering is in use.
boolean	containsKey ( Object key) Returns whether this `Map` contains the specified key. This implementation iterates its key set, looking for a key that `key` equals.
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.
Set < Entry <K, V>>	entrySet () Returns a `Set` containing all of the mappings in this `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 least key in this sorted 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 of the mapping with the specified key. This implementation iterates its entry set, looking for an entry with a key that `key` equals.
NavigableMap <K, V>	headMap (K to, boolean inclusive) Returns a view of the portion of this map whose keys are less than (or equal to, if `inclusive` is true) `toKey` .
SortedMap <K, V>	headMap (K toExclusive) Returns a sorted map over a range of this sorted map with all keys that are less than the specified `endKey` . Equivalent to `headMap(toKey, false)` .
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.
boolean	isEmpty () Returns whether this map is empty. This implementation compares `size()` to 0.
Set <K>	keySet () Returns a set of the keys contained in this `Map` . This implementation returns a view that calls through this to 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 greatest key in this sorted 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.
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.
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 (K key, V value) Maps the specified key to the specified value. This base implementation throws `UnsupportedOperationException` .
V	remove ( Object key) Removes a mapping with the specified key from this `Map` . This implementation iterates its entry set, removing the entry with a key that `key` equals.
int	size () Returns the number of mappings in this `Map` . This implementation returns its entry set's size.
SortedMap <K, V>	subMap (K fromInclusive, K toExclusive) Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified `startKey` and less than the specified `endKey` . Equivalent to `subMap(fromKey, true, toKey, false)` .
NavigableMap <K, V>	subMap (K from, boolean fromInclusive, K to, boolean toInclusive) Returns a view of the portion of this map whose keys range from `fromKey` to `toKey` .
NavigableMap <K, V>	tailMap (K from, boolean inclusive) Returns a view of the portion of this map whose keys are greater than (or equal to, if `inclusive` is true) `fromKey` .
SortedMap <K, V>	tailMap (K fromInclusive) Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified `startKey` . Equivalent to `tailMap(fromKey, true)` .

[Expand]

Inherited Methods

From class java.util.AbstractMap

void	clear () Removes all elements from this `Map` , leaving it empty. This implementation calls `entrySet().clear()` .
Object	clone () Creates and returns a copy of this `Object` .
boolean	containsKey ( Object key) Returns whether this `Map` contains the specified key. This implementation iterates its key set, looking for a key that `key` equals.
boolean	containsValue ( Object value) Returns whether this `Map` contains the specified value. This implementation iterates its entry set, looking for an entry with a value that `value` equals.
abstract Set < Entry <K, V>>	entrySet () Returns a `Set` containing all of the mappings in this `Map` .
boolean	equals ( Object object) Compares this instance with the specified object and indicates if they are equal. This implementation first checks the structure of `object` .
V	get ( Object key) Returns the value of the mapping with the specified key. This implementation iterates its entry set, looking for an entry with a key that `key` equals.
int	hashCode () Returns an integer hash code for this object. This implementation iterates its entry set, summing the hashcodes of its entries.
boolean	isEmpty () Returns whether this map is empty. This implementation compares `size()` to 0.
Set <K>	keySet () Returns a set of the keys contained in this `Map` . This implementation returns a view that calls through this to map.
V	put (K key, V value) Maps the specified key to the specified value. This base implementation throws `UnsupportedOperationException` .
void	)">putAll ( Map <? extends K, ? extends V> map) Copies every mapping in the specified `Map` to this `Map` . This implementation iterates through `map` 's entry set, calling `put()` for each.
V	remove ( Object key) Removes a mapping with the specified key from this `Map` . This implementation iterates its entry set, removing the entry with a key that `key` equals.
int	size () Returns the number of mappings in this `Map` . This implementation returns its entry set's size.
String	toString () Returns a string containing a concise, human-readable description of this object. This implementation composes a string by iterating its entry set.
Collection <V>	values () Returns a `Collection` of the values contained in this `Map` . This implementation returns a view that calls through this to map.

From class java.lang.Object

Object	clone () Creates and returns a copy of this `Object` .
boolean	equals ( Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize () Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class <?>	getClass () Returns the unique instance of `Class` that represents this object's class.
int	hashCode () Returns an integer hash code for this object.
final void	notify () Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll () Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString () Returns a string containing a concise, human-readable description of this object.
final void	wait () Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait (long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait (long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

From interface java.util.Map

abstract void	clear () Removes all elements from this `Map` , leaving it empty.
abstract boolean	containsKey ( Object key) Returns whether this `Map` contains the specified key.
abstract boolean	containsValue ( Object value) Returns whether this `Map` contains the specified value.
abstract Set < Entry <K, V>>	entrySet () Returns a `Set` containing all of the mappings in this `Map` .
abstract boolean	equals ( Object object) Compares the argument to the receiver, and returns `true` if the specified object is a `Map` and both `Map` s contain the same mappings.
abstract V	get ( Object key) Returns the value of the mapping with the specified key.
abstract int	hashCode () Returns an integer hash code for the receiver.
abstract boolean	isEmpty () Returns whether this map is empty.
abstract Set <K>	keySet () Returns a set of the keys contained in this `Map` .
abstract V	put (K key, V value) Maps the specified key to the specified value.
abstract void	)">putAll ( Map <? extends K, ? extends V> map) Copies every mapping in the specified `Map` to this `Map` .
abstract V	remove ( Object key) Removes a mapping with the specified key from this `Map` .
abstract int	size () Returns the number of mappings in this `Map` .
abstract Collection <V>	values () Returns a `Collection` of the values contained in this `Map` .

From interface java.util.NavigableMap

abstract 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.
abstract K	ceilingKey (K key) Returns the least key greater than or equal to the given key, or `null` if there is no such key.
abstract NavigableSet <K>	descendingKeySet () Returns a reverse order `NavigableSet` view of the keys contained in this map.
abstract NavigableMap <K, V>	descendingMap () Returns a reverse order view of the mappings contained in this map.
abstract Entry <K, V>	firstEntry () Returns a key-value mapping associated with the least key in this map, or `null` if the map is empty.
abstract 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.
abstract K	floorKey (K key) Returns the greatest key less than or equal to the given key, or `null` if there is no such key.
abstract 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` .
abstract SortedMap <K, V>	headMap (K toKey) Returns a sorted map over a range of this sorted map with all keys that are less than the specified `endKey` . Equivalent to `headMap(toKey, false)` .
abstract 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.
abstract K	higherKey (K key) Returns the least key strictly greater than the given key, or `null` if there is no such key.
abstract Entry <K, V>	lastEntry () Returns a key-value mapping associated with the greatest key in this map, or `null` if the map is empty.
abstract 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.
abstract K	lowerKey (K key) Returns the greatest key strictly less than the given key, or `null` if there is no such key.
abstract NavigableSet <K>	navigableKeySet () Returns a `NavigableSet` view of the keys contained in this map.
abstract 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.
abstract 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.
abstract SortedMap <K, V>	subMap (K fromKey, K toKey) Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified `startKey` and less than the specified `endKey` . Equivalent to `subMap(fromKey, true, toKey, false)` .
abstract 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` .
abstract SortedMap <K, V>	tailMap (K fromKey) Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified `startKey` . Equivalent to `tailMap(fromKey, true)` .
abstract 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` .

From interface java.util.SortedMap

abstract Comparator <? super K>	comparator () Returns the comparator used to compare keys in this sorted map, or null if the natural ordering is in use.
abstract K	firstKey () Returns the least key in this sorted map.
abstract SortedMap <K, V>	headMap (K endKey) Returns a sorted map over a range of this sorted map with all keys that are less than the specified `endKey` .
abstract K	lastKey () Returns the greatest key in this sorted map.
abstract SortedMap <K, V>	subMap (K startKey, K endKey) Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified `startKey` and less than the specified `endKey` .
abstract SortedMap <K, V>	tailMap (K startKey) Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified `startKey` .

Public Constructors

public TreeMap ()

Added in API level 1

Create a natural order, empty tree map whose keys must be mutually comparable and non-null.

)">

public TreeMap ( Map <? extends K, ? extends V> copyFrom)

Added in API level 1

Create a natural order tree map populated with the key/value pairs of copyFrom . This map's keys must be mutually comparable and non-null.

Even if copyFrom is a SortedMap , the constructed map will not use copyFrom 's ordering. This constructor always creates a naturally-ordered map. Because the TreeMap constructor overloads are ambiguous, prefer to construct a map and populate it in two steps:

          
           TreeMap
           
            customOrderedMap
       = new TreeMap
           
           
            (copyFrom.comparator());
   customOrderedMap.putAll(copyFrom);

)">

public TreeMap ( Comparator <? super K> comparator)

Added in API level 1

Create a tree map ordered by comparator . This map's keys may only be null if comparator permits.

Parameters

comparator	the comparator to order elements with, or `null` to use the natural ordering.

)">

public TreeMap ( SortedMap <K, ? extends V> copyFrom)

Added in API level 1

Create a tree map with the ordering and key/value pairs of copyFrom . This map's keys may only be null if the copyFrom 's ordering permits.

The constructed map will always use copyFrom 's ordering. Because the TreeMap constructor overloads are ambiguous, prefer to construct a map and populate it in two steps:

          
           TreeMap
           
            customOrderedMap
       = new TreeMap
           
           
            (copyFrom.comparator());
   customOrderedMap.putAll(copyFrom);

Public Methods

public Entry <K, V> ceilingEntry (K key)

Added in API level 9

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.

Parameters

key	the key

Returns

an entry with the least key greater than or equal to key , or null if there is no such key

public K ceilingKey (K key)

Added in API level 9

Returns the least key greater than or equal to the given key, or null if there is no such key.

Parameters

key	the key

Returns

the least key greater than or equal to key , or null if there is no such key

public void clear ()

Added in API level 1

Removes all elements from this Map , leaving it empty.

This implementation calls entrySet().clear() .

public Object clone ()

Added in API level 1

Creates and returns a copy of this Object . The default implementation returns a so-called "shallow" copy: It creates a new instance of the same class and then copies the field values (including object references) from this instance to the new instance. A "deep" copy, in contrast, would also recursively clone nested objects. A subclass that needs to implement this kind of cloning should call super.clone() to create the new instance and then create deep copies of the nested, mutable objects.

Returns

a copy of this object.

public Comparator <? super K> comparator ()

Added in API level 1

Returns the comparator used to compare keys in this sorted map, or null if the natural ordering is in use.

public boolean containsKey ( Object key)

Added in API level 1

Returns whether this Map contains the specified key.

This implementation iterates its key set, looking for a key that key equals.

Parameters

key	the key to search for.

Returns

true if this map contains the specified key, false otherwise.

public NavigableSet <K> descendingKeySet ()

Added in API level 9

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. 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 the Iterator.remove , Set.remove , removeAll , retainAll , and clear operations. It does not support the add or addAll operations.

Returns

a reverse order navigable set view of the keys in this map

public NavigableMap <K, V> descendingMap ()

Added in API level 9

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 own remove operation), the results of the iteration are undefined.

The returned map has an ordering equivalent to )">Collections.reverseOrder (comparator()) . The expression m.descendingMap().descendingMap() returns a view of m essentially equivalent to m .

Returns

a reverse order view of this map

public Set < Entry <K, V>> entrySet ()

Added in API level 1

Returns a Set containing all of the mappings in this Map . Each mapping is an instance of Map.Entry . As the Set is backed by this Map , changes in one will be reflected in the other.

Returns

a set of the mappings

public Entry <K, V> firstEntry ()

Added in API level 9

Returns a key-value mapping associated with the least key in this map, or null if the map is empty.

public K firstKey ()

Added in API level 1

Returns the least key in this sorted map.

public Entry <K, V> floorEntry (K key)

Added in API level 9

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.

Parameters

key	the key

Returns

an entry with the greatest key less than or equal to key , or null if there is no such key

public K floorKey (K key)

Added in API level 9

Returns the greatest key less than or equal to the given key, or null if there is no such key.

Parameters

key	the key

Returns

the greatest key less than or equal to key , or null if there is no such key

public V get ( Object key)

Added in API level 1

Returns the value of the mapping with the specified key.

This implementation iterates its entry set, looking for an entry with a key that key equals.

Parameters

key	the key.

Returns

the value of the mapping with the specified key, or null if no mapping for the specified key is found.

public NavigableMap <K, V> headMap (K to, boolean inclusive)

Added in API level 9

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.

Parameters

to	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

public SortedMap <K, V> headMap (K toExclusive)

Added in API level 1

Returns a sorted map over a range of this sorted map with all keys that are less than the specified endKey . Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Equivalent to headMap(toKey, false) .

Parameters

toExclusive	the high boundary of the range specified.

Returns

a sorted map where the keys are less than endKey .

public Entry <K, V> higherEntry (K key)

Added in API level 9

Returns a key-value mapping associated with the least key strictly greater than the given key, or null if there is no such key.

Parameters

key	the key

Returns

an entry with the least key greater than key , or null if there is no such key

public K higherKey (K key)

Added in API level 9

Returns the least key strictly greater than the given key, or null if there is no such key.

Parameters

key	the key

Returns

the least key greater than key , or null if there is no such key

public boolean isEmpty ()

Added in API level 1

Returns whether this map is empty.

This implementation compares size() to 0.

Returns

true if this map has no elements, false otherwise.

public Set <K> keySet ()

Added in API level 1

Returns a set of the keys contained in this Map . The Set is backed by this Map so changes to one are reflected by the other. The Set does not support adding.

This implementation returns a view that calls through this to map. Its iterator transforms this map's entry set iterator to return keys.

Returns

a set of the keys.

public Entry <K, V> lastEntry ()

Added in API level 9

Returns a key-value mapping associated with the greatest key in this map, or null if the map is empty.

public K lastKey ()

Added in API level 1

Returns the greatest key in this sorted map.

public Entry <K, V> lowerEntry (K key)

Added in API level 9

Returns a key-value mapping associated with the greatest key strictly less than the given key, or null if there is no such key.

Parameters

key	the key

Returns

an entry with the greatest key less than key , or null if there is no such key

public K lowerKey (K key)

Added in API level 9

Returns the greatest key strictly less than the given key, or null if there is no such key.

Parameters

key	the key

Returns

the greatest key less than key , or null if there is no such key

public NavigableSet <K> navigableKeySet ()

Added in API level 9

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. 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 the Iterator.remove , Set.remove , removeAll , retainAll , and clear operations. It does not support the add or addAll operations.

Returns

a navigable set view of the keys in this map

public Entry <K, V> pollFirstEntry ()

Added in API level 9

Removes and returns a key-value mapping associated with the least key in this map, or null if the map is empty.

Returns

the removed first entry of this map, or null if this map is empty

public Entry <K, V> pollLastEntry ()

Added in API level 9

Removes and returns a key-value mapping associated with the greatest key in this map, or null if the map is empty.

Returns

the removed last entry of this map, or null if this map is empty

public V put (K key, V value)

Added in API level 1

Maps the specified key to the specified value.

This base implementation throws UnsupportedOperationException .

Parameters

key	the key.
value	the value.

Returns

the value of any previous mapping with the specified key or null if there was no mapping.

public V remove ( Object key)

Added in API level 1

Removes a mapping with the specified key from this Map .

This implementation iterates its entry set, removing the entry with a key that key equals.

Parameters

key	the key of the mapping to remove.

Returns

the value of the removed mapping or null if no mapping for the specified key was found.

public int size ()

Added in API level 1

Returns the number of mappings in this Map .

This implementation returns its entry set's size.

Returns

the number of mappings in this Map .

public SortedMap <K, V> subMap (K fromInclusive, K toExclusive)

Added in API level 1

Returns a sorted map over a range of this sorted map with all keys greater than or equal to the specified startKey and less than the specified endKey . Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Equivalent to subMap(fromKey, true, toKey, false) .

Parameters

fromInclusive	the low boundary of the range (inclusive).
toExclusive	the high boundary of the range (exclusive),

Returns

a sorted map with the key from the specified range.

public NavigableMap <K, V> subMap (K from, boolean fromInclusive, K to, boolean toInclusive)

Added in API level 9

Returns a view of the portion of this map whose keys range from fromKey to toKey . If fromKey and toKey are equal, the returned map is empty unless fromExclusive 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.

Parameters

from	low endpoint of the keys in the returned map
fromInclusive	`true` if the low endpoint is to be included in the returned view
to	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 from fromKey to toKey

public NavigableMap <K, V> tailMap (K from, boolean inclusive)

Added in API level 9

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.

Parameters

from	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

public SortedMap <K, V> tailMap (K fromInclusive)

Added in API level 1

Returns a sorted map over a range of this sorted map with all keys that are greater than or equal to the specified startKey . Changes to the returned sorted map are reflected in this sorted map and vice versa.

Note: The returned map will not allow an insertion of a key outside the specified range.

Equivalent to tailMap(fromKey, true) .

Parameters

fromInclusive	the low boundary of the range specified.

Returns

a sorted map where the keys are greater or equal to startKey .

Results

Interfaces

Classes

Enums

Exceptions

Errors

TreeMap

Class Overview

Summary

Public Constructors

public TreeMap ()

public TreeMap ( Map <? extends K, ? extends V> copyFrom)

public TreeMap ( Comparator <? super K> comparator)

Parameters

public TreeMap ( SortedMap <K, ? extends V> copyFrom)

Public Methods

public Entry <K, V> ceilingEntry (K key)

Parameters

Returns

public K ceilingKey (K key)

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public void clear ()

public Object clone ()

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public Comparator <? super K> comparator ()

public boolean containsKey ( Object key)

Parameters

Returns

public NavigableSet <K> descendingKeySet ()

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public NavigableMap <K, V> descendingMap ()

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public Set < Entry <K, V>> entrySet ()

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public Entry <K, V> firstEntry ()

public K firstKey ()

public Entry <K, V> floorEntry (K key)

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public K floorKey (K key)

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public V get ( Object key)

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public NavigableMap <K, V> headMap (K to, boolean inclusive)

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public SortedMap <K, V> headMap (K toExclusive)

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public Entry <K, V> higherEntry (K key)

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Returns

public K higherKey (K key)

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public boolean isEmpty ()

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public Set <K> keySet ()

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public Entry <K, V> lastEntry ()

public K lastKey ()

public Entry <K, V> lowerEntry (K key)

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public K lowerKey (K key)

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public NavigableSet <K> navigableKeySet ()

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public Entry <K, V> pollFirstEntry ()

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public Entry <K, V> pollLastEntry ()

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public V put (K key, V value)

Parameters

Returns

public V remove ( Object key)