org.dromara.hutool.core.map

类 SafeConcurrentHashMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

java.util.concurrent.ConcurrentHashMap<K,V>

org.dromara.hutool.core.map.SafeConcurrentHashMap<K,V>

类型参数:

K - 键类型

V - 值类型

所有已实现的接口:

Serializable, ConcurrentMap<K,V>, Map<K,V>

public class SafeConcurrentHashMap<K,V>
extends ConcurrentHashMap<K,V>

安全的ConcurrentHashMap实现
此类用于解决在JDK8中调用ConcurrentHashMap.computeIfAbsent(Object, Function)可能造成的死循环问题。
见：issues#2349

相关bug见：@see https://bugs.openjdk.java.net/browse/JDK-8161372

另请参阅:

序列化表格

嵌套类概要

从类继承的嵌套类/接口 java.util.concurrent.ConcurrentHashMap

ConcurrentHashMap.KeySetView<K,V>

从类继承的嵌套类/接口 java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

从接口继承的嵌套类/接口 java.util.Map

Map.Entry<K,V>

构造器概要

构造器

构造器和说明
SafeConcurrentHashMap() 构造，默认初始大小（16）
SafeConcurrentHashMap(int initialCapacity) 构造
SafeConcurrentHashMap(int initialCapacity, float loadFactor) 构造
SafeConcurrentHashMap(int initialCapacity, float loadFactor, int concurrencyLevel) 构造
SafeConcurrentHashMap(Map<? extends K,? extends V> m) 构造

方法概要

限定符和类型	方法和说明
V	computeIfAbsent(K key, Function<? super K,? extends V> mappingFunction)

从类继承的方法 java.util.concurrent.ConcurrentHashMap

clear, compute, computeIfPresent, contains, containsKey, containsValue, elements, entrySet, equals, forEach, forEach, forEach, forEachEntry, forEachEntry, forEachKey, forEachKey, forEachValue, forEachValue, get, getOrDefault, hashCode, isEmpty, keys, keySet, keySet, mappingCount, merge, newKeySet, newKeySet, put, putAll, putIfAbsent, reduce, reduceEntries, reduceEntries, reduceEntriesToDouble, reduceEntriesToInt, reduceEntriesToLong, reduceKeys, reduceKeys, reduceKeysToDouble, reduceKeysToInt, reduceKeysToLong, reduceToDouble, reduceToInt, reduceToLong, reduceValues, reduceValues, reduceValuesToDouble, reduceValuesToInt, reduceValuesToLong, remove, remove, replace, replace, replaceAll, search, searchEntries, searchKeys, searchValues, size, toString, values

从类继承的方法 java.util.AbstractMap

clone

从类继承的方法 java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

构造器详细资料

SafeConcurrentHashMap

public SafeConcurrentHashMap()

构造，默认初始大小（16）

SafeConcurrentHashMap

public SafeConcurrentHashMap(int initialCapacity)

构造

参数:

initialCapacity - 预估初始大小

SafeConcurrentHashMap

public SafeConcurrentHashMap(Map<? extends K,? extends V> m)

构造

参数:

m - 初始键值对

SafeConcurrentHashMap

public SafeConcurrentHashMap(int initialCapacity,
                             float loadFactor)

构造

参数:

initialCapacity - 初始容量

loadFactor - 增长系数

SafeConcurrentHashMap

public SafeConcurrentHashMap(int initialCapacity,
                             float loadFactor,
                             int concurrencyLevel)

构造

参数:

initialCapacity - 初始容量

loadFactor - 增长系数

concurrencyLevel - 并发级别，即Segment的个数

方法详细资料

computeIfAbsent

public V computeIfAbsent(K key,
                         Function<? super K,? extends V> mappingFunction)

指定者:

computeIfAbsent 在接口中 ConcurrentMap<K,V>

指定者:

computeIfAbsent 在接口中 Map<K,V>

覆盖:

computeIfAbsent 在类中 ConcurrentHashMap<K,V>