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How to Use Topic Patterns in MapRStreams Data Objects

How to Use Topic Patterns in MapRStreams Data Objects

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Regular Expression Syntax Guidelines

Regular Expression Syntax Guidelines

You must use perl compatible regular expression syntax when you create a regular expression.

The following table describes perl compatible regular expression syntax guidelines to create a regular expression:

Syntax	Description
. (a period)	Matches any one character.
[a-z]	Matches one instance of a character in lower case. For example, [a-z] matches ab. Use [A-Z] to match characters in upper case.
\d	Matches one instance of any digit from 0-9.
\s	Matches a whitespace character.
\w	Matches one alphanumeric character, including underscore (_)
()	Groups an expression. For example, the parentheses in (\d-\d-\d\d) groups the expression \d\d-\d\d, which finds any two numbers followed by a hyphen and any two numbers, as in 12-34.
{}	Matches the number of characters. For example, \d{3} matches any three numbers, such as 650 or 510. Or, [a-z]{2} matches any two letters, such as CA or NY.
?	Matches the preceding character or group of characters zero or one time. For example, \d{3}(-{d{4})? matches any three numbers, which can be followed by a hyphen and any four numbers.
* (an asterisk)	Matches zero or more instances of the values that follow the asterisk. For example, *0 is any value that precedes a 0.
+	Matches one or more instances of the values that follow the plus sign. For example, \w+ is any value that follows an alphanumeric character.

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