Why is there no direct implemention of Bag in java collection framework? -


i can't figure out why jcf (java collection framework) does't have bag implementation(to allow duplicates , not maintain order). bag performance better current collection implementations in jcf.

  • i know how implement bag in java.
  • i know there bag collection in apache common.
  • i know can use implementation bag! there work in other implementations compare bag.

why has java collections framework not provided direct implementations this?

posting comment answer since answers question best.

from bug report filed here :

there isn't lot of enthusiasm among maintainers of collection framework design , implement these interfaces/classes. can't recall having needed one. more popular package developed outside jdk imported jdk after having proved worth in real world.

the need having support bags valid today.

guava has support it. gs-collections.


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