Certain special character constructs are allowed literally in Java regular expressions. Here they are:
| Special Character | Meaning |
| \0c | A character with the octal value c |
| \0cc | A character with the octal value cc |
| \0ncc | A character with the octal value ncc, where n cannot be more than 3 |
| \xhh | A character with the hexadecimal value 0xhh |
| \uhhhh | A character with the hexadecimal value 0xhhhh |
| \x{h...h} | A character with the hexadecimal value 0xh...h, where h must be a valid CODE_POINT |
| \n | Newline character or u000A |
| \t | Tab character or u0009 |
| \r | Carriage return character or u000D |
| \f | Form feed character or u000C |
| \e | Escape character or u\u001B |
| \a | Bell character or \u0007 |
| \cn | A control character represented by n |
