如何在 fastutils 中实现线程安全或不可变集合？

Question

Fastutil seems to be the fastest option for collections in Java.

Answer 1

Each map type has its own synchronized wrapper class (eg Long2ObjectMaps.SynchronizedMap as you linked above). To use it, instantiate a concrete map implementation, then use the corresponding …Maps.synchronize() method to get the synchronized version:

Long2ObjectMap<Foo> unsynched = new Long2ObjectOpenHashMap<>();

// this is actually a Long2ObjectMaps.SynchronizedMap
Long2ObjectMap<Foo> synched = Long2ObjectMaps.synchronize(unsynchronized);

Answer 2

There is a lightweight thread-safe alternative: FastUtil Concurrent Wrapper<\/a> .