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Is there any equivalent in google Guava for apache commons' CollectionUtils.isEmpty(list) to check if a collection is null or empty?
谷歌Guava中是否有任何等效的apache commons的CollectionUtils.isEmpty（列表）来检查集合是否为空或空？
1 个解决方案
#1
5
To check if Collection is both null and empty, you must do null check by yourself. Guava devs advocate not to use nulls for Collections at all - see IdeaGraveyard on Guava Wiki:
要检查Collection是否为空和空，您必须自己进行空检查。 Guava开发人员主张不对集合使用空值 - 请参阅Guava Wiki上的IdeaGraveyard：
Prefer to return empty collections instead of null. Then a plain isEmpty check will suffice.
更喜欢返回空集合而不是null。然后一个简单的isEmpty检查就足够了。
EDIT:
编辑：
See this SO answer by Guava's lead dev.
请参阅Guava的主要开发人员的回答。
#1
5
To check if Collection is both null and empty, you must do null check by yourself. Guava devs advocate not to use nulls for Collections at all - see IdeaGraveyard on Guava Wiki:
要检查Collection是否为空和空，您必须自己进行空检查。 Guava开发人员主张不对集合使用空值 - 请参阅Guava Wiki上的IdeaGraveyard：
Prefer to return empty collections instead of null. Then a plain isEmpty check will suffice.
更喜欢返回空集合而不是null。然后一个简单的isEmpty检查就足够了。
EDIT:
编辑：
See this SO answer by Guava's lead dev.
请参阅Guava的主要开发人员的回答。