Array setBoolean() Method in Java with Examples

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 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 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 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 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