Java.util.Arrays.fill() Method

---

---

Description

The java.util.Arrays.fill(boolean[] a, int fromIndex, int toIndex, boolean val) method assigns the specified boolean value to each element of the specified range of the specified array of booleans.The range to be filled extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be filled is empty.)

Declaration

Following is the declaration for java.util.Arrays.fill() method

public static void fill(boolean[] a, int fromIndex, int toIndex, boolean val)

Parameters

• a − This is the array to be filled.

• fromIndex − This is the index of the first element (inclusive) to be filled with the specified value.

• toIndex − This is the index of the last element (exclusive) to be filled with the specified value.

• val − This is the value to be stored in all elements of the array.

Return Value

This method does not return any value.

Exception

• ArrayIndexOutOfBoundsException − if fromIndex < 0 or toIndex > a.length

• IllegalArgumentException − if fromIndex > toIndex

Example

The following example shows the usage of java.util.Arrays.fill() method.

package com.tutorialspoint;

import java.util.Arrays;

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

      // initializing boolean array
      boolean arr[] = new boolean[] {true, true, true, true, true};

      // let us print the values
      System.out.println("Actual values: ");
      for (boolean value : arr) {
         System.out.println("Value = " + value);
      }

      // using fill for placing false from index 1 to 4
      Arrays.fill(arr, 1, 4, false);

      // let us print the values
      System.out.println("New values after using fill() method: ");
      for (boolean value : arr) {
         System.out.println("Value = " + value);
      }
   }
} 

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

Actual values:
Value = true
Value = true
Value = true
Value = true
Value = true
New values after using fill() method:
Value = true
Value = false
Value = false
Value = false
Value = true