I am trying to simply read words in a text file using scanner.next() with delimiter equal " " but the scanner includes the newline/carriage return with the token.
I have scoured the internet trying to find a good example of this problem and have not found it so I am posting it here. I can't find another similar problem posted here on SO. I also looked over the documentation on scanner and pattern (http://docs.oracle.com/javase/1.5.0/docs/api/java/util/regex/Pattern.html) but I still cannot find a way to solve this.
Text file:
This is a test
to see if1 this, is working
ok!
Code:
int i = 0;
String string;
try(Scanner scanner = new Scanner(new File(filename))) {
scanner.useDelimiter(" ");
while(scanner.hasNext())
{
string = scanner.next();
System.out.println(i++ + ": " + string);
}
}catch(IOException io_error) {
System.out.println(io_error);
}
Output:
0: This
1: is
2: a
3: test
to
4: see
5: if1
6: this,
7: is
8: working
ok!
As you can see, #3 and #8 have two words separated by a newline. (I know I can separate these into two separate strings.)
The documentation of Scanner says:
The default whitespace delimiter used by a scanner is as recognized by
Character.isWhitespace
And the linked documentation of Character.isWhitespace
says:
Determines if the specified character is white space according to Java. A character is a Java whitespace character if and only if it satisfies one of the following criteria:
- It is a Unicode space character (SPACE_SEPARATOR, LINE_SEPARATOR, or PARAGRAPH_SEPARATOR) but is not also a non-breaking space ('\u00A0', '\u2007', '\u202F').
- It is '\t', U+0009 HORIZONTAL TABULATION.
- It is '\n', U+000A LINE FEED.
- It is '\u000B', U+000B VERTICAL TABULATION.
- It is '\f', U+000C FORM FEED.
- It is '\r', U+000D CARRIAGE RETURN.
- It is '\u001C', U+001C FILE SEPARATOR.
- It is '\u001D', U+001D GROUP SEPARATOR.
- It is '\u001E', U+001E RECORD SEPARATOR.
- It is '\u001F', U+001F UNIT SEPARATOR.
So, just don't set any specific delimiter. Keep the default, and newlines will be considered as a delimiter just like spaces, which means the token won't include newline characters.