Java stream api 的 Collectors.toList toMap 是直接 new ArrayList 和 new HashMap 而没有额外指定容量，这个对数据处理类的应用的性能会有多大影响？ - V2EX
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Leviathann
V2EX    Java

Java stream api 的 Collectors.toList toMap 是直接 new ArrayList 和 new HashMap 而没有额外指定容量，这个对数据处理类的应用的性能会有多大影响？

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  •   Leviathann Jul 25, 2021 1991 views
    This topic created in 1737 days ago, the information mentioned may be changed or developed.

    比如从 kafka 读数据然后处理啥的

  • new
  • hashmap
  • Kafka
  • tomap
    1 replies    2021-07-25 21:56:25 +08:00
    aragakiyuii
        1
    aragakiyuii  
       Jul 25, 2021 via iPhone
    这个得根据数据量来看会扩充多少次吧
    java stream api 是可以指定 downStream 的
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