Java 如何使用正则表达式在短语后打印单词

它必须使用正则表达式用java编写
我需要在“什么是”之后打印一个单词 输入：

So what is java regex
what is operator in java

输出：

java
operator

java
operator

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只需使用lookback将紧跟其后的字符串与lookback中与模式匹配的字符串进行匹配

(?<=what is )\\S+

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如果必须是正则表达式，我会保持简单，并使用a来匹配和捕获“what is”后面的单词

注意：您需要引用匹配组

#1

以返回匹配结果

说明：

what       # 'what'
\s         # whitespace (\n, \r, \t, \f, and " ")
is         # 'is'
\s         # whitespace (\n, \r, \t, \f, and " ")
(          # group and capture to \1:
  \w+      #   word characters (a-z, A-Z, 0-9, _) (1 or more times)
)          # end of \1

java
operator

what\sis\s(\w+)

what       # 'what'
\s         # whitespace (\n, \r, \t, \f, and " ")
is         # 'is'
\s         # whitespace (\n, \r, \t, \f, and " ")
(          # group and capture to \1:
  \w+      #   word characters (a-z, A-Z, 0-9, _) (1 or more times)
)          # end of \1