How can I use named capture groups in Java before Java 7?

Named Groups with Regular Expressions in Java

Regular expression packages have limitations

java.regex package I have confirmed that there is no support for named groups, so please let me know which third-party libraries support it.

I looked into jregex, but the last release was in 2002 and it didn't work for java5 (though I tried it right away).

Support since Java 7

Java 7 added support for named groups. The building blocks to support named capture groups are:

• '(?capturing "text)"
• "k" to backreference the named group "name"
• "$" to refer to the captured group in the Matcher's replacement string {name}"
• "Matcher.group(String

Alternatives for Java 7 and earlier

For Java 7 and earlier, there were the following alternatives:

• Google named-regex
• jregex

Regex2 library

Regex2 library supports named groups It extends the java.util.regex.Pattern class to create .

Example

Input string: "TEST 123"

Regular expression: "(?w ) (?

Access:

matcher.group(1) == "TEST"
matcher.group("login") == "TEST"
matcher.name( 1) == "login"

Replace:

matcher.replaceAll("aaaaa_$1_sssss_$2____") == "aaaaa_TEST_sssss_123____"
matcher.replaceAll("aaaaa_${login}_sssss_${id}____") == "aaaaa_TEST_sssss_123____"

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