| 9 |
|
|
| 10 |
|
/** |
| 11 |
|
* A {@link SortedSet} extended with navigation methods reporting |
| 12 |
< |
* closest matches for given search targets. Methods <tt>lower</tt>, |
| 13 |
< |
* <tt>floor</tt>, <tt>ceiling</tt>, and <tt>higher</tt> return keys |
| 12 |
> |
* closest matches for given search targets. Methods {@code lower}, |
| 13 |
> |
* {@code floor}, {@code ceiling}, and {@code higher} return keys |
| 14 |
|
* respectively less than, less than or equal, greater than or equal, |
| 15 |
< |
* and greater than a given key, returning <tt>null</tt> if there is |
| 16 |
< |
* no such key. A <tt>NavigableSet</tt> may be viewed and traversed |
| 17 |
< |
* in either ascending or descending order. The <tt>Collection</tt> |
| 18 |
< |
* <tt>iterator</tt> method returns an ascending <tt>Iterator</tt> and |
| 19 |
< |
* the additional method <tt>descendingIterator</tt> returns |
| 15 |
> |
* and greater than a given key, returning {@code null} if there is |
| 16 |
> |
* no such key. A {@code NavigableSet} may be viewed and traversed |
| 17 |
> |
* in either ascending or descending order. The {@code Collection} |
| 18 |
> |
* {@code iterator} method returns an ascending {@code Iterator} and |
| 19 |
> |
* the additional method {@code descendingIterator} returns |
| 20 |
|
* descending iterator. The performance of ascending traversals is |
| 21 |
|
* likely to be faster than descending traversals. This interface |
| 22 |
< |
* additionally defines methods <tt>pollFirst</tt> and |
| 22 |
> |
* additionally defines methods {@code pollFirst} and |
| 23 |
|
* <t>pollLast</tt> that return and remove the lowest and highest key, |
| 24 |
< |
* if one exists, else returning <tt>null</tt>. |
| 24 |
> |
* if one exists, else returning {@code null}. |
| 25 |
|
* |
| 26 |
|
* <p>The return values of navigation methods may be ambiguous in |
| 27 |
< |
* implementations that permit <tt>null</tt> elements. However, even |
| 27 |
> |
* implementations that permit {@code null} elements. However, even |
| 28 |
|
* in this case the result can be disambiguated by checking |
| 29 |
< |
* <tt>contains(null)</tt>. To avoid such issues, implementations of |
| 29 |
> |
* {@code contains(null)}. To avoid such issues, implementations of |
| 30 |
|
* this interface are encouraged <em>not</em> to permit insertion of |
| 31 |
< |
* <tt>null</tt> elements. (Note that sorted sets of {@link |
| 32 |
< |
* Comparable} elements intrinsically do not permit <tt>null</tt>.) |
| 31 |
> |
* {@code null} elements. (Note that sorted sets of {@link |
| 32 |
> |
* Comparable} elements intrinsically do not permit {@code null}.) |
| 33 |
|
* |
| 34 |
|
* @author Doug Lea |
| 35 |
|
* @param <E> the type of elements maintained by this set |
| 37 |
|
public interface NavigableSet<E> extends SortedSet<E> { |
| 38 |
|
/** |
| 39 |
|
* Returns an element greater than or equal to the given element, or |
| 40 |
< |
* <tt>null</tt> if there is no such element. |
| 40 |
> |
* {@code null} if there is no such element. |
| 41 |
|
* |
| 42 |
|
* @param o the value to match |
| 43 |
|
* @return an element greater than or equal to given element, or |
| 44 |
< |
* <tt>null</tt> if there is no such element. |
| 44 |
> |
* {@code null} if there is no such element. |
| 45 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 46 |
|
* currently in the set. |
| 47 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 48 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 47 |
> |
* @throws NullPointerException if o is {@code null} |
| 48 |
> |
* and this set deas not permit {@code null} elements |
| 49 |
|
*/ |
| 50 |
|
public E ceiling(E o); |
| 51 |
|
|
| 52 |
|
/** |
| 53 |
|
* Returns an element strictly less than the given element, or |
| 54 |
< |
* <tt>null</tt> if there is no such element. |
| 54 |
> |
* {@code null} if there is no such element. |
| 55 |
|
* |
| 56 |
|
* @param o the value to match |
| 57 |
|
* @return the greatest element less than the given element, or |
| 58 |
< |
* <tt>null</tt> if there is no such element. |
| 58 |
> |
* {@code null} if there is no such element. |
| 59 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 60 |
|
* currently in the set |
| 61 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 62 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 61 |
> |
* @throws NullPointerException if o is {@code null} |
| 62 |
> |
* and this set deas not permit {@code null} elements |
| 63 |
|
*/ |
| 64 |
|
public E lower(E o); |
| 65 |
|
|
| 66 |
|
/** |
| 67 |
|
* Returns an element less than or equal to the given element, or |
| 68 |
< |
* <tt>null</tt> if there is no such element. |
| 68 |
> |
* {@code null} if there is no such element. |
| 69 |
|
* |
| 70 |
|
* @param o the value to match |
| 71 |
|
* @return the greatest element less than or equal to given |
| 72 |
< |
* element, or <tt>null</tt> if there is no such element |
| 72 |
> |
* element, or {@code null} if there is no such element |
| 73 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 74 |
|
* currently in the set |
| 75 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 76 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 75 |
> |
* @throws NullPointerException if o is {@code null} |
| 76 |
> |
* and this set deas not permit {@code null} elements |
| 77 |
|
*/ |
| 78 |
|
public E floor(E o); |
| 79 |
|
|
| 80 |
|
/** |
| 81 |
|
* Returns an element strictly greater than the given element, or |
| 82 |
< |
* <tt>null</tt> if there is no such element. |
| 82 |
> |
* {@code null} if there is no such element. |
| 83 |
|
* |
| 84 |
|
* @param o the value to match |
| 85 |
|
* @return the least element greater than the given element, or |
| 86 |
< |
* <tt>null</tt> if there is no such element. |
| 86 |
> |
* {@code null} if there is no such element. |
| 87 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 88 |
|
* currently in the set |
| 89 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 90 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 89 |
> |
* @throws NullPointerException if o is {@code null} |
| 90 |
> |
* and this set deas not permit {@code null} elements |
| 91 |
|
*/ |
| 92 |
|
public E higher(E o); |
| 93 |
|
|
| 94 |
|
/** |
| 95 |
|
* Retrieves and removes the first (lowest) element. |
| 96 |
|
* |
| 97 |
< |
* @return the first element, or <tt>null</tt> if empty |
| 97 |
> |
* @return the first element, or {@code null} if empty |
| 98 |
|
*/ |
| 99 |
|
public E pollFirst(); |
| 100 |
|
|
| 101 |
|
/** |
| 102 |
|
* Retrieves and removes the last (highest) element. |
| 103 |
|
* |
| 104 |
< |
* @return the last element, or <tt>null</tt> if empty |
| 104 |
> |
* @return the last element, or {@code null} if empty |
| 105 |
|
*/ |
| 106 |
|
public E pollLast(); |
| 107 |
|
|
| 109 |
|
* Returns an iterator over the elements in this collection, in |
| 110 |
|
* descending order. |
| 111 |
|
* |
| 112 |
< |
* @return an <tt>Iterator</tt> over the elements in this collection |
| 112 |
> |
* @return an {@code Iterator} over the elements in this collection |
| 113 |
|
*/ |
| 114 |
|
Iterator<E> descendingIterator(); |
| 115 |
|
|
| 116 |
|
/** |
| 117 |
|
* Returns a view of the portion of this set whose elements range from |
| 118 |
< |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, exclusive. (If |
| 119 |
< |
* <tt>fromElement</tt> and <tt>toElement</tt> are equal, the returned |
| 118 |
> |
* {@code fromElement}, inclusive, to {@code toElement}, exclusive. (If |
| 119 |
> |
* {@code fromElement} and {@code toElement} are equal, the returned |
| 120 |
|
* sorted set is empty.) The returned sorted set is backed by this set, |
| 121 |
|
* so changes in the returned sorted set are reflected in this set, and |
| 122 |
|
* vice-versa. |
| 123 |
|
* @param fromElement low endpoint (inclusive) of the subSet |
| 124 |
|
* @param toElement high endpoint (exclusive) of the subSet |
| 125 |
|
* @return a view of the portion of this set whose elements range from |
| 126 |
< |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, |
| 126 |
> |
* {@code fromElement}, inclusive, to {@code toElement}, |
| 127 |
|
* exclusive |
| 128 |
< |
* @throws ClassCastException if <tt>fromElement</tt> and |
| 129 |
< |
* <tt>toElement</tt> cannot be compared to one another using |
| 128 |
> |
* @throws ClassCastException if {@code fromElement} and |
| 129 |
> |
* {@code toElement} cannot be compared to one another using |
| 130 |
|
* this set's comparator (or, if the set has no comparator, |
| 131 |
|
* using natural ordering) |
| 132 |
< |
* @throws IllegalArgumentException if <tt>fromElement</tt> is |
| 133 |
< |
* greater than <tt>toElement</tt> |
| 134 |
< |
* @throws NullPointerException if <tt>fromElement</tt> or |
| 135 |
< |
* <tt>toElement</tt> is <tt>null</tt> |
| 136 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 132 |
> |
* @throws IllegalArgumentException if {@code fromElement} is |
| 133 |
> |
* greater than {@code toElement} |
| 134 |
> |
* @throws NullPointerException if {@code fromElement} or |
| 135 |
> |
* {@code toElement} is {@code null} |
| 136 |
> |
* and this set deas not permit {@code null} elements |
| 137 |
|
*/ |
| 138 |
|
public NavigableSet<E> subSet(E fromElement, E toElement); |
| 139 |
|
|
| 140 |
|
/** |
| 141 |
|
* Returns a view of the portion of this set whose elements are strictly |
| 142 |
< |
* less than <tt>toElement</tt>. The returned sorted set is backed by |
| 142 |
> |
* less than {@code toElement}. The returned sorted set is backed by |
| 143 |
|
* this set, so changes in the returned sorted set are reflected in this |
| 144 |
|
* set, and vice-versa. |
| 145 |
|
* @param toElement high endpoint (exclusive) of the headSet |
| 146 |
|
* @return a view of the portion of this set whose elements are strictly |
| 147 |
|
* less than toElement |
| 148 |
< |
* @throws ClassCastException if <tt>toElement</tt> is not compatible |
| 148 |
> |
* @throws ClassCastException if {@code toElement} is not compatible |
| 149 |
|
* with this set's comparator (or, if the set has no comparator, |
| 150 |
< |
* if <tt>toElement</tt> does not implement <tt>Comparable</tt>) |
| 151 |
< |
* @throws NullPointerException if <tt>toElement</tt> is <tt>null</tt> |
| 152 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 150 |
> |
* if {@code toElement} does not implement {@code Comparable}) |
| 151 |
> |
* @throws NullPointerException if {@code toElement} is {@code null} |
| 152 |
> |
* and this set deas not permit {@code null} elements |
| 153 |
|
*/ |
| 154 |
|
public NavigableSet<E> headSet(E toElement); |
| 155 |
|
|
| 156 |
|
/** |
| 157 |
|
* Returns a view of the portion of this set whose elements are |
| 158 |
< |
* greater than or equal to <tt>fromElement</tt>. The returned |
| 158 |
> |
* greater than or equal to {@code fromElement}. The returned |
| 159 |
|
* sorted set is backed by this set, so changes in the returned |
| 160 |
|
* sorted set are reflected in this set, and vice-versa. |
| 161 |
|
* @param fromElement low endpoint (inclusive) of the tailSet |
| 162 |
|
* @return a view of the portion of this set whose elements are |
| 163 |
< |
* greater than or equal to <tt>fromElement</tt> |
| 164 |
< |
* @throws ClassCastException if <tt>fromElement</tt> is not |
| 163 |
> |
* greater than or equal to {@code fromElement} |
| 164 |
> |
* @throws ClassCastException if {@code fromElement} is not |
| 165 |
|
* compatible with this set's comparator (or, if the set has no |
| 166 |
< |
* comparator, if <tt>fromElement</tt> does not implement |
| 167 |
< |
* <tt>Comparable</tt>) |
| 168 |
< |
* @throws NullPointerException if <tt>fromElement</tt> is <tt>null</tt> |
| 169 |
< |
* and this set deas not permit <tt>null</tt> elements |
| 166 |
> |
* comparator, if {@code fromElement} does not implement |
| 167 |
> |
* {@code Comparable}) |
| 168 |
> |
* @throws NullPointerException if {@code fromElement} is {@code null} |
| 169 |
> |
* and this set deas not permit {@code null} elements |
| 170 |
|
*/ |
| 171 |
|
public NavigableSet<E> tailSet(E fromElement); |
| 172 |
|
} |
