Java Scanner useDelimiter() Method

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Description

The java Scanner useDelimiter(Pattern pattern) method sets this scanner's delimiting pattern to the specified pattern.

Declaration

Following is the declaration for java.util.Scanner.useDelimiter() method

public Scanner useDelimiter(Pattern pattern)

Parameters

pattern − A delimiting pattern

Return Value

This method returns this scanner

Exception

NA

Java Scanner useDelimiter(String pattern) Method

Description

The Java Scanner useDelimiter(String pattern) method Sets this scanner's delimiting pattern to a pattern constructed from the specified String.

Declaration

Following is the declaration for java.util.Scanner.useDelimiter() method

public Scanner useDelimiter(String pattern)

Parameters

pattern − A string specifying a delimiting pattern

Return Value

This method returns this scanner

Exception

NA

Setting Delimiter of a Scanner on a String Example

The following example shows the usage of Java Scanner useDelimiter(Pattern pattern) method to use a delimiter pattern for scanner. We've created a scanner object using a given string. We've printed a line using nextLine() method and then set a delimiter to print it. Then scanner is closed using close() method.

package com.tutorialspoint;

import java.util.Scanner;
import java.util.regex.Pattern;

public class ScannerDemo {
   public static void main(String[] args) {

      String s = "Hello World! 3 + 3.0 = 6.0 true ";

      // create a new scanner with the specified String Object
      Scanner scanner = new Scanner(s);

      // print a line of the scanner
      System.out.println(scanner.nextLine());

      // change the delimiter of this scanner
      scanner.useDelimiter(Pattern.compile(".ll."));

      // display the new delimiter
      System.out.println(scanner.delimiter());

      // close the scanner
      scanner.close();
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Hello World! 3 + 3.0 = 6.0 true 
.ll.

Setting Delimiter of a Scanner on User Input Example

The following example shows the usage of Java Scanner useDelimiter(Pattern pattern) method to use a delimiter pattern for scanner. We've created a scanner object using System.in class. We've printed a line using nextLine() method and then set a delimiter to print it. Then scanner is closed using close() method.

package com.tutorialspoint;

import java.util.Scanner;
import java.util.regex.Pattern;

public class ScannerDemo {
   public static void main(String[] args) {

      // create a new scanner with the System.in class
      Scanner scanner = new Scanner(System.in);

      // print a line of the scanner
      System.out.println(scanner.nextLine());

      // change the delimiter of this scanner
      scanner.useDelimiter(Pattern.compile(".ll."));

      // display the new delimiter
      System.out.println(scanner.delimiter());

      // close the scanner
      scanner.close();
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Hello World
Hello World
.ll.

Setting Delimiter of a Scanner on a Properties File Example

The following example shows the usage of Java Scanner useDelimiter(String pattern) method to use a delimiter pattern for scanner. We've created a scanner object using properties.txt file. We've printed a line using nextLine() method and then set a delimiter to print it. Then scanner is closed using close() method.

package com.tutorialspoint;

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

public class ScannerDemo {
   public static void main(String[] args) throws FileNotFoundException {

      // create a new scanner with a file as input
      Scanner scanner = new Scanner(new File("properties.txt"));

      // print a line of the scanner
      System.out.println(scanner.nextLine());

      // change the delimiter of this scanner
      scanner.useDelimiter(".ll.");

      // display the new delimiter
      System.out.println(scanner.delimiter());

      // close the scanner
      scanner.close();
   }
}

Assuming we have a file properties.txt available in your CLASSPATH, with the following content. This file will be used as an input for our example program −

Hello World! 3 + 3.0 = 6

Output

Let us compile and run the above program, this will produce the following result −

Hello World! 3 + 3.0 = 6
.ll.