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Préférences
Moteurs de recherche
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JavaTM 2 Platform Std. Ed. v1.5.0
java.util
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Nested Class Summary |
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Nested classes/interfaces inherited from interface java.util.Map |
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Map.Entry<K,V> |
Method Summary | |
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Comparator<? super K> |
comparator()
Returns the comparator associated with this sorted map, or null if it uses its keys' natural ordering. |
K |
firstKey()
Returns the first (lowest) key currently in this sorted map. |
SortedMap<K,V> |
headMap(K toKey)
Returns a view of the portion of this sorted map whose keys are strictly less than toKey. |
K |
lastKey()
Returns the last (highest) key currently in this sorted map. |
SortedMap<K,V> |
subMap(K fromKey,
K toKey)
Returns a view of the portion of this sorted map whose keys range from fromKey, inclusive, to toKey, exclusive. |
SortedMap<K,V> |
tailMap(K fromKey)
Returns a view of the portion of this sorted map whose keys are greater than or equal to fromKey. |
Methods inherited from interface java.util.Map |
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clear, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values |
Method Detail |
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Comparator<? super K> comparator()
SortedMap<K,V> subMap(K fromKey, K toKey)
The map returned by this method will throw an IllegalArgumentException if the user attempts to insert a key outside the specified range.
Note: this method always returns a half-open range (which includes its low endpoint but not its high endpoint). If you need a closed range (which includes both endpoints), and the key type allows for calculation of the successor a given key, merely request the subrange from lowEndpoint to successor(highEndpoint). For example, suppose that m is a map whose keys are strings. The following idiom obtains a view containing all of the key-value mappings in m whose keys are between low and high, inclusive:
Map sub = m.subMap(low, high+"\0");A similarly technique can be used to generate an open range (which contains neither endpoint). The following idiom obtains a view containing all of the key-value mappings in m whose keys are between low and high, exclusive:
Map sub = m.subMap(low+"\0", high);
fromKey
- low endpoint (inclusive) of the subMap.toKey
- high endpoint (exclusive) of the subMap.
ClassCastException
- 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.
IllegalArgumentException
- if fromKey is greater than
toKey; or if this map is itself a subMap, headMap,
or tailMap, and fromKey or toKey are not
within the specified range of the subMap, headMap, or tailMap.
NullPointerException
- if fromKey or toKey is
null and this sorted map does not tolerate
null keys.SortedMap<K,V> headMap(K toKey)
The map returned by this method will throw an IllegalArgumentException if the user attempts to insert a key outside the specified range.
Note: this method always returns a view that does not contain its (high) endpoint. If you need a view that does contain this endpoint, and the key type allows for calculation of the successor a given key, merely request a headMap bounded by successor(highEndpoint). For example, suppose that suppose that m is a map whose keys are strings. The following idiom obtains a view containing all of the key-value mappings in m whose keys are less than or equal to high:
Map head = m.headMap(high+"\0");
toKey
- high endpoint (exclusive) of the subMap.
ClassCastException
- 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.
IllegalArgumentException
- if this map is itself a subMap,
headMap, or tailMap, and toKey is not within the
specified range of the subMap, headMap, or tailMap.
NullPointerException
- if toKey is null and
this sorted map does not tolerate null keys.SortedMap<K,V> tailMap(K fromKey)
The map returned by this method will throw an IllegalArgumentException if the user attempts to insert a key outside the specified range.
Note: this method always returns a view that contains its (low) endpoint. If you need a view that does not contain this endpoint, and the element type allows for calculation of the successor a given value, merely request a tailMap bounded by successor(lowEndpoint). For example, suppose that suppose that m is a map whose keys are strings. The following idiom obtains a view containing all of the key-value mappings in m whose keys are strictly greater than low:
Map tail = m.tailMap(low+"\0");
fromKey
- low endpoint (inclusive) of the tailMap.
ClassCastException
- 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.
IllegalArgumentException
- if this map is itself a subMap,
headMap, or tailMap, and fromKey is not within the
specified range of the subMap, headMap, or tailMap.
NullPointerException
- if fromKey is null and
this sorted map does not tolerate null keys.K firstKey()
NoSuchElementException
- if this map is empty.K lastKey()
NoSuchElementException
- if this map is empty.