public final class Pump extends Object
| Constructor and Description |
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Pump() |
| Modifier and Type | Method and Description |
|---|---|
static <E,K,V> long |
buildTreeMap(Iterator<E> source,
Engine engine,
Fun.Function1<K,E> keyExtractor,
Fun.Function1<V,E> valueExtractor,
boolean ignoreDuplicates,
int nodeSize,
boolean valuesStoredOutsideNodes,
long counterRecid,
BTreeKeySerializer<K> keySerializer,
Serializer<V> valueSerializer,
Comparator comparator)
Build BTreeMap (or TreeSet) from presorted data.
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static <E> Iterator<E> |
merge(Iterator... iters)
Merges multiple iterators into single iterator.
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static <E> Iterator<E> |
sort(Comparator comparator,
boolean mergeDuplicates,
Iterator... iterators)
Merge presorted iterators into single sorted iterator.
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static <E> Iterator<E> |
sort(Iterator<E> source,
boolean mergeDuplicates,
int batchSize,
Comparator comparator,
Serializer serializer)
Sorts large data set by given `Comparator`.
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public static <E> Iterator<E> sort(Iterator<E> source, boolean mergeDuplicates, int batchSize, Comparator comparator, Serializer serializer)
source - iterator over unsorted datamergeDuplicates - should be duplicate keys merged into single one?batchSize - how much items can fit into heap memorycomparator - used to sort dataserializer - used to store data in temporary filespublic static <E> Iterator<E> sort(Comparator comparator, boolean mergeDuplicates, Iterator... iterators)
comparator - used to compare datamergeDuplicates - if duplicate keys should be merged into single oneiterators - array of already sorted iteratorspublic static <E> Iterator<E> merge(Iterator... iters)
iters - - iterators to be mergedpublic static <E,K,V> long buildTreeMap(Iterator<E> source, Engine engine, Fun.Function1<K,E> keyExtractor, Fun.Function1<V,E> valueExtractor, boolean ignoreDuplicates, int nodeSize, boolean valuesStoredOutsideNodes, long counterRecid, BTreeKeySerializer<K> keySerializer, Serializer<V> valueSerializer, Comparator comparator)
sort(java.util.Iterator, boolean, int, java.util.Comparator, Serializer)
This method does not call commit. You should disable Write Ahead Log when this method is used DBMaker.transactionDisable()source - iterator over source data, must be reverse sortedkeyExtractor - transforms items from source iterator into keys. If null source items will be used directly as keys.valueExtractor - transforms items from source iterator into values. If null BTreeMap will be constructed without values (as Set)ignoreDuplicates - should be duplicate keys merged into single one?nodeSize - maximal BTree node size before it is splited.valuesStoredOutsideNodes - if true values will not be stored as part of BTree nodescounterRecid - TODO make size counter friendly to usekeySerializer - serializer for keys, use null for default valuevalueSerializer - serializer for value, use null for default valuecomparator - comparator used to compare keys, use null for 'comparable comparator'IllegalArgumentException - if source iterator is not reverse sortedCopyright © 2024. All rights reserved.