Matching Across Line Boundaries in a Regular Expression
By default, the any-character matcher (.) does not match line
termination characters such as \n and \r. To allow dot
(.) to match line termination characters, the pattern should be
compiled with the dotall flag enabled.
It is also possible to enable dotall mode within a pattern
using the inline modifier (?s). For example, dotall mode is
enabled in the pattern (?s)a.*b. Dotall mode can be disabled
using (?-s).
CharSequence inputStr = "abc\ndef";
String patternStr = ".*c.+d.*";
// Compile with dotall enabled
Pattern pattern = Pattern.compile(patternStr, Pattern.DOTALL);
Matcher matcher = pattern.matcher(inputStr);
boolean matchFound = matcher.matches(); // true
// Use an inline modifier to enable dotall mode
matchFound = pattern.matches(".*c.+d.*", "abc\r\ndef"); // false
matchFound = pattern.matches("(?s).*c.+d.*", "abc\r\ndef"); // true
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