reactor.netty.internal.util

Class MapUtils

java.lang.Object

reactor.netty.internal.util.MapUtils

public final class MapUtils
extends Object

It's a temporary workaround for Java 8 specific performance issue JDK-8161372 and this class should be removed once the Java 8 support is dropped.

Note: This utility class is for internal use only. It can be removed at any time.

Since:

1.0.15

Author:

zimatars

Method Summary

Modifier and Type	Method and Description
static <K,V> V	computeIfAbsent(Map<K,V> map, K key, Function<K,V> mappingFunction) ConcurrentHashMap.computeIfAbsent(k,v) locks when k is present.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

computeIfAbsent

public static <K,V> V computeIfAbsent(Map<K,V> map,
                                      K key,
                                      Function<K,V> mappingFunction)

ConcurrentHashMap.computeIfAbsent(k,v) locks when k is present. Add pre-screen before locking inside computeIfAbsent.

Note: This utility is not for a general purpose usage. Carefully consider the removal operations from the map. If you have many remove operations that are critical, do not use this pre-screening.

Parameters:

map - the ConcurrentHashMap instance

key - key with which the specified value is to be associated

mappingFunction - the function to compute a value

Returns:

the current (existing or computed) value associated with the specified key, or null if the computed value is null