using Scanner with a bar ("|") delimiter

[cumin]

When I use "|" as a delimiter, my program seems to take each character
as a new token, instead of tokenizing at the bar. When I use ":" as the
delimiter, I get what I expect when reading "delim.txt".

Am I doing something incorrectly?

"delim.txt":
100:|first:|second:|third
200:|alpha:|beta:|gamma
300:|roy:|gee:|biv


Here is the program:
package scantext;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class TheClass {

private static void readFile(String filename, String delim) {
try {
File file = new File(filename);
Scanner scanner = new Scanner(file);
scanner.useDelimiter(System.getProperty("line.separator"));
while (scanner.hasNext()) {
System.out.println();
String theNext = scanner.next();
System.out.println(theNext);
parseline(theNext, delim);
}
scanner.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}

public static void parseline(String line, String delim) {
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter(delim);
System.out.println("delimiter is >" + lineScanner.delimiter() + "<");
int a = lineScanner.nextInt();
String b = lineScanner.next();
String c = lineScanner.next();
String d = lineScanner.next();
System.out.println(
"a = " + a +
", b= " + b +
", c = " + c +
", d = " + d);
}

public static void main(String[] args) {
readFile("delim.txt", "|");
System.out.println();
readFile("delim.txt", ":");
}
}


The output is:

100:|first:|second:|third
delimiter is >|<
a = 1, b= 0, c = 0, d = :

200:|alpha:|beta:|gamma
delimiter is >|<
a = 2, b= 0, c = 0, d = :

300:|roy:|gee:|biv
delimiter is >|<
a = 3, b= 0, c = 0, d = :


100:|first:|second:|third
delimiter is >:<
a = 100, b= |first, c = |second, d = |third

200:|alpha:|beta:|gamma
delimiter is >:<
a = 200, b= |alpha, c = |beta, d = |gamma

300:|roy:|gee:|biv
delimiter is >:<
a = 300, b= |roy, c = |gee, d = |biv

 

[cumin]

When I use "|" as a delimiter, my program seems to take each character
as a new token, instead of tokenizing at the bar. When I use ":" as the
delimiter, I get what I expect when reading "delim.txt".

Am I doing something incorrectly?

"delim.txt":
100:|first:|second:|third
200:|alpha:|beta:|gamma
300:|roy:|gee:|biv

Here is the program:
package scantext;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class TheClass {

private static void readFile(String filename, String delim) {
try {
File file = new File(filename);
Scanner scanner = new Scanner(file);
scanner.useDelimiter(System.getProperty("line.separator"));
while (scanner.hasNext()) {
System.out.println();
String theNext = scanner.next();
System.out.println(theNext);
parseline(theNext, delim);
}
scanner.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}

public static void parseline(String line, String delim) {
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter(delim);
System.out.println("delimiter is >" + lineScanner.delimiter() + "<");
int a = lineScanner.nextInt();
String b = lineScanner.next();
String c = lineScanner.next();
String d = lineScanner.next();
System.out.println(
"a = " + a +
", b= " + b +
", c = " + c +
", d = " + d);
}

public static void main(String[] args) {
readFile("delim.txt", "|");
System.out.println();
readFile("delim.txt", ":");
}

}The output is:

100:|first:|second:|third
delimiter is >|<
a = 1, b= 0, c = 0, d = :

200:|alpha:|beta:|gamma
delimiter is >|<
a = 2, b= 0, c = 0, d = :

300:|roy:|gee:|biv
delimiter is >|<
a = 3, b= 0, c = 0, d = :

100:|first:|second:|third
delimiter is >:<
a = 100, b= |first, c = |second, d = |third

200:|alpha:|beta:|gamma
delimiter is >:<
a = 200, b= |alpha, c = |beta, d = |gamma

300:|roy:|gee:|biv
delimiter is >:<
a = 300, b= |roy, c = |gee, d = |biv

never mind...

 

[Andreas Leitgeb]

When I use "|" as a delimiter, my program seems to take each character
as a new token, instead of tokenizing at the bar. When I use ":" as the
delimiter, I get what I expect when reading "delim.txt".

The String you pass as delimiter is actually a Pattern.
"|" as a (regex-)Pattern means "empty or empty", so any
string matches, so every position in your input matches
the delimiter-pattern, so each char is a token on its own.

Use "\\|" to specify a pattern that actually matches only
the literal pipe-char. (you need two backslashes, because
parsing java-string literals "eats" one of them away.)

 

[Alex Hunsley]

When I use "|" as a delimiter, my program seems to take each character
as a new token, instead of tokenizing at the bar. When I use ":" as the
delimiter, I get what I expect when reading "delim.txt".

Am I doing something incorrectly?

[snip]

a = 300, b= |roy, c = |gee, d = |biv

never mind...

Glad you got it sorted. It's often useful in these circumstances (where
you work out the problem yourself) to say what the problem was - it's
helpful to others (educational) - and shows you're interested in
contributing, rather than just getting a question answered.

lex