Array setBoolean() Method in Java with Examples Last Updated : 30 Nov, 2018 Summarize Comments Improve Suggest changes Share Like Article Like Report The java.lang.reflect.Array.setBoolean() method is an inbuilt method used to set a specified Boolean value to a specified index of a given object array. Syntax: Array.setBoolean(Object []array, int index, boolean value) Parameter: This method takes three parameters: array: array of type Object which is to be updated. index: index of the array which is to be updated. value: boolean value that is to be set at the given index of the given array. Return type: This is a void type method and doesn't returns any value. The update reflects upon the Object array passed as the argument. Exception: This method throws following exceptions: NullPointerException– when the array is null. IllegalArgumentException– when the given object array is not an Array. ArrayIndexOutOfBoundsException– if the given index is not in the range of the size of the array. Below is the implementation of Array.setBoolean() method: Program 1: Java // Java code to demonstrate setBoolean() // method of Array class import java.lang.reflect.Array; public class GfG { // main method public static void main(String[] args) { // Declaring and defining boolean array boolean b[] = { true, false, true }; // array before using setBoolean() System.out.print("Before Set : "); // printing the array for (boolean x : b) { System.out.print(x + " "); } // boolean value to be set boolean value = true; // setBoolean method of class Array Array.setBoolean(b, 1, value); // array after using setBoolean() System.out.print("\nAfter Set : "); // printing array for (boolean x : b) { System.out.print(x + " "); } } } Output: Before Set : true false true After Set : true true true Program 2: To demonstrate java.lang.NullPointerException Java // Java code to demonstrate setBoolean() // method of Array class import java.lang.reflect.Array; public class GfG { // main method public static void main(String[] args) { // Declaring and defining boolean array to null boolean b[] = null; try { // boolean value to be set boolean c = false; // passing a null array as parameter Array.setBoolean(b, 5, c); } catch (Exception e) { System.out.println("Exception : " + e); } } } Output: Exception : java.lang.NullPointerException Program 3: To demonstrate java.lang.ArrayIndexOutOfBoundsException Java // Java code to demonstrate setBoolean() // method of Array class import java.lang.reflect.Array; public class GfG { // main method public static void main(String[] args) { // Declaring and defining boolean array boolean b[] = { true, false, true }; try { // value to be set boolean c = false; // passing index as 5 when size is 3 Array.setBoolean(b, 5, c); } catch (Exception e) { System.out.println("Exception : " + e); } } } Output: Exception : java.lang.ArrayIndexOutOfBoundsException Program 4: To demonstrate java.lang.IllegalArgumentException Java // Java code to demonstrate setBoolean() // method of Array class import java.lang.reflect.Array; public class GfG { // main method public static void main(String[] args) { // Declaring and defining boolean variable boolean b = true; try { // value to be set boolean c = false; // passing variable in the place of an array Array.setBoolean(b, 5, c); } catch (Exception e) { System.out.println("Exception : " + e); } } } Output: Exception : java.lang.IllegalArgumentException: Argument is not an array Comment More infoAdvertise with us Next Article Array setBoolean() Method in Java with Examples S ShivamKD Follow Improve Article Tags : Java java-basics Java-lang package java-reflection-array java-lang-reflect-package +1 More Practice Tags : Java Similar Reads Field setBoolean() method in Java with Examples The setBoolean() method of java.lang.reflect.Field used to set the value of a field as a boolean on the specified object. 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