CODEWITHSUNDEEP
javastringsplitdelimiter
Vicky
Vicky

Reputation: 17375

String delimiter in string.split method

I have following data:

1||1||Abdul-Jabbar||Karim||1996||1974

I want to delimit the tokens.

Here the delimiter is "||".

My delimiter setter is:

public void setDelimiter(String delimiter) {
    char[] c = delimiter.toCharArray();
    this.delimiter = "\"" + "\\" + c[0] + "\\" + c[1] + "\"";
    System.out.println("Delimiter string is: " + this.delimiter);
}

However, 

String[] tokens = line.split(delimiter);

is not giving the required result.

Upvotes: 45

Views: 235084

Answers (10)

Sanjay T. Sharma
Sanjay T. Sharma

Reputation: 23208

Use the Pattern#quote() method for escaping ||. Try:

final String[] tokens = myString.split(Pattern.quote("||"));

This is required because | is an alternation character and hence gains a special meaning when passed to split call (basically the argument to split is a regular expression in string form).

Upvotes: 35

Yesh
Yesh

Reputation: 318

String[] strArray= str.split(Pattern.quote("||"));

where

  1. str = "1||1||Abdul-Jabbar||Karim||1996||1974";
  2. Pattern.quote("||") will ignore the special character.
  3. .split function will split the string for every occurrence of ||.
  4. strArray will have the array of string that is delimited by ||.

Upvotes: 6

Bohemian
Bohemian

Reputation: 425013

Split uses regex, and the pipe char | has special meaning in regex, so you need to escape it. There are a few ways to do this, but here's the simplest:

String[] tokens = line.split("\\|\\|");

Upvotes: 3

Manoj Kumar
Manoj Kumar

Reputation: 1

StringTokenizer st = new StringTokenizer("1||1||Abdul-Jabbar||Karim||1996||1974",
             "||");
while(st.hasMoreTokens()){
     System.out.println(st.nextElement());
}

Answer will print

1 1 Abdul-Jabbar Karim 1996 1974

Upvotes: 0

Pedro Lobito
Pedro Lobito

Reputation: 98921

String[] splitArray = subjectString.split("\\|\\|");

You use a function:

public String[] stringSplit(String string){

    String[] splitArray = string.split("\\|\\|");
    return splitArray;
}

Upvotes: 0

Raze
Raze

Reputation: 2224

The problem is because you are adding quotes to your delimiter. It should be removed, and it will work fine.

public void setDelimiter(String delimiter) {
    char[] c = delimiter.toCharArray();
    this.delimiter = "\\" + c[0] + "\\" + c[1];
    System.out.println("Delimiter string is: " + this.delimiter);
}

Upvotes: 0

Ray Toal
Ray Toal

Reputation: 88378

There is no need to set the delimiter by breaking it up in pieces like you have done.

Here is a complete program you can compile and run:

import java.util.Arrays;
public class SplitExample {
    public static final String PLAYER = "1||1||Abdul-Jabbar||Karim||1996||1974";
    public static void main(String[] args) {
        String[] data = PLAYER.split("\\|\\|");
        System.out.println(Arrays.toString(data));
    }
}

If you want to use split with a pattern, you can use Pattern.compile or Pattern.quote.

To see compile and quote in action, here is an example using all three approaches:

import java.util.Arrays;
import java.util.regex.Pattern;
public class SplitExample {
    public static final String PLAYER = "1||1||Abdul-Jabbar||Karim||1996||1974";
    public static void main(String[] args) {
        String[] data = PLAYER.split("\\|\\|");
        System.out.println(Arrays.toString(data));

        Pattern pattern = Pattern.compile("\\|\\|");
        data = pattern.split(PLAYER);
        System.out.println(Arrays.toString(data));

        pattern = Pattern.compile(Pattern.quote("||"));
        data = pattern.split(PLAYER);
        System.out.println(Arrays.toString(data));
    }
}

The use of patterns is recommended if you are going to split often using the same pattern. BTW the output is:

[1, 1, Abdul-Jabbar, Karim, 1996, 1974]
[1, 1, Abdul-Jabbar, Karim, 1996, 1974]
[1, 1, Abdul-Jabbar, Karim, 1996, 1974]

Upvotes: 65

shinkou
shinkou

Reputation: 5154

There is something wrong in your setDelimiter() function. You don't want to double quote the delimiters, do you?

public void setDelimiter(String delimiter) {
    char[] c = delimiter.toCharArray();
    this.delimiter = "\\" + c[0] + "\\" + c[1];
    System.out.println("Delimiter string is: " + this.delimiter);
}

However, as other users have said, it's better to use the Pattern.quote() method to escape your delimiter if your requirements permit.

Upvotes: 0

Nirmit Shah
Nirmit Shah

Reputation: 758

Pipe (|) is a special character in regex. to escape it, you need to prefix it with backslash (\). But in java, backslash is also an escape character. so again you need to escape it with another backslash. So your regex should be \\|\\| e.g, String[] tokens = myString.split("\\|\\|");

Upvotes: 5

Mark Peters
Mark Peters

Reputation: 81074

Double quotes are interpreted as literals in regex; they are not special characters. You are trying to match a literal "||".

Just use Pattern.quote(delimiter):

As requested, here's a line of code (same as Sanjay's)

final String[] tokens = line.split(Pattern.quote(delimiter));

If that doesn't work, you're not passing in the correct delimiter.

Upvotes: 9

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