16 lines
459 B
Java
16 lines
459 B
Java
package com.baeldung.distinct;
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import java.util.Map;
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import java.util.concurrent.ConcurrentHashMap;
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import java.util.function.Function;
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import java.util.function.Predicate;
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public class DistinctWithJavaFunction {
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public static <T> Predicate<T> distinctByKey(Function<? super T, ?> keyExtractor) {
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Map<Object, Boolean> seen = new ConcurrentHashMap<>();
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return t -> seen.putIfAbsent(keyExtractor.apply(t), Boolean.TRUE) == null;
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}
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}
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