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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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package extra166y; |
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|
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import jsr166y.*; |
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import static extra166y.Ops.*; |
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import java.util.*; |
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import java.util.concurrent.atomic.*; |
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|
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/** |
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* A prefix view of ParallelArray that causes operations to apply |
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* only to elements within a given range. |
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* Instances of this class may be constructed only via prefix |
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* methods of ParallelArray or its other prefix classes. |
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*/ |
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public abstract class ParallelArrayWithBounds<T> extends ParallelArrayWithFilter<T> { |
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ParallelArrayWithBounds |
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(ForkJoinPool ex, int origin, int fence, T[] array) { |
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super(ex, origin, fence, array); |
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} |
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|
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/** |
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* Returns an operation prefix that causes a method to operate |
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* only on the elements of the array between firstIndex |
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* (inclusive) and upperBound (exclusive). The bound |
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* arguments are relative to the current bounds. For example |
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* {@code pa.withBounds(2, 8).withBounds(3, 5)} indexes the |
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* 5th (= 2+3) and 6th elements of pa. However, indices |
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* returned by methods such as {@code indexOf} are |
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* with respect to the underlying ParallelArray. |
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* @param firstIndex the lower bound (inclusive) |
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* @param upperBound the upper bound (exclusive) |
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* @return operation prefix |
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*/ |
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public abstract ParallelArrayWithBounds<T> withBounds |
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(int firstIndex, int upperBound); |
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|
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/** |
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* Returns the index of some element equal to given target, or |
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* -1 if not present. |
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* @param target the element to search for |
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* @return the index or -1 if not present |
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*/ |
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public abstract int indexOf(T target); |
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|
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/** |
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* Assuming this array is sorted, returns the index of an |
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* element equal to given target, or -1 if not present. If the |
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* array is not sorted, the results are undefined. |
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* @param target the element to search for |
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* @return the index or -1 if not present |
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*/ |
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public abstract int binarySearch(T target); |
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|
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/** |
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* Assuming this array is sorted with respect to the given |
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* comparator, returns the index of an element equal to given |
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* target, or -1 if not present. If the array is not sorted, |
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* the results are undefined. |
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* @param target the element to search for |
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* @param comparator the comparator |
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* @return the index or -1 if not present |
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*/ |
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public abstract int binarySearch(T target, |
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Comparator<? super T> comparator); |
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/** |
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* Replaces each element with the running cumulation of applying |
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* the given reducer. |
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* @param reducer the reducer |
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* @param base the result for an empty array |
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* @return this (to simplify use in expressions) |
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*/ |
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public abstract ParallelArrayWithBounds<T> cumulate(Reducer<T> reducer, T base); |
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|
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/** |
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* Replaces each element with the cumulation of applying the given |
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* reducer to all previous values, and returns the total |
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* reduction. |
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* @param reducer the reducer |
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* @param base the result for an empty array |
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* @return the total reduction |
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*/ |
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public abstract T precumulate(Reducer<T> reducer, T base); |
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|
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/** |
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* Sorts the elements. |
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* Unlike Arrays.sort, this sort does |
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* not guarantee that elements with equal keys maintain their |
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* relative position in the array. |
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* @param cmp the comparator to use |
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* @return this (to simplify use in expressions) |
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*/ |
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public abstract ParallelArrayWithBounds<T> sort(Comparator<? super T> cmp); |
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|
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/** |
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* Sorts the elements, assuming all elements are |
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* Comparable. Unlike Arrays.sort, this sort does not |
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* guarantee that elements with equal keys maintain their relative |
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* position in the array. |
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* @return this (to simplify use in expressions) |
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* @throws ClassCastException if any element is not Comparable |
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*/ |
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public abstract ParallelArrayWithBounds<T> sort(); |
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} |