The dot cannot be used inside character classes.
See the option Pattern.DOTALL.
Pattern.DOTALL
Enables dotall mode. In dotall mode, the expression .
matches any character, including a line terminator. By default this expression does not match line terminators. Dotall mode can also be enabled via the embedded flag expression (?s)
. (The s is a mnemonic for "single-line" mode, which is what this is called in Perl.)
If you need it on just a portion of the regular expression, you use e.g. [sS]
.
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