Array setDouble() method in Java

The java.lang.reflect.Array.setDouble() is an inbuilt method in Java and is used to set a specified double value to a specified index of a given object array.

Syntax:

Array.setDouble(Object []array, int index, double value)

Parameter: This method takes three parameters:

• array: This is an array of type Object which is to be updated.
• index: This is the index of the array which is to be updated.
• value: This is the double value that is to be set at the given index of the given array.

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.setDouble() method:

Program 1:








// Java code to demonstrate setDouble() // method of Array class    import java.lang.reflect.Array;    public class GfG {        // main method     public static void main(String[] args)     {         // Declaring and defining double array         double f[] = { 1.0, 2.0, 3.0 };            // printing the array         System.out.print("Before Set : ");         for (double x : f) {             System.out.print(x + " ");         }            double value = 400.0;            // setDouble method of class Array         Array.setDouble(f, 1, value);            // printing array         System.out.print("\nAfter Set : ");         for (double x : f) {             System.out.print(x + " ");         }     } }
Output:

Before Set : 1.0 2.0 3.0 
After Set : 1.0 400.0 3.0

Program 2: To demonstrate java.lang.NullPointerException








// Java code to demonstrate setDouble() // method of Array class    import java.lang.reflect.Array;    public class GfG {        // main method     public static void main(String[] args)     {         // Declaring and defining double array to null         double b[] = null;            try {             double c = 1.0;                // setDouble method of class Array             // passing null array in parameters             Array.setDouble(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 setDouble() // method of Array class    import java.lang.reflect.Array;    public class GfG {        // main method     public static void main(String[] args)     {         // Declaring and defining double array         double b[] = { 1.0, 2.0, 3.0 };            try {             double c = 1.0;                // setDouble method of class Array             // passing index 5 when size is 3             Array.setDouble(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 setDouble() // method of Array class    import java.lang.reflect.Array;    public class GfG {        // main method     public static void main(String[] args)     {         // Declaring and defining double variable         double b = 2.0;         try {             double c = 1.0;             // setDouble method of class Array             // passing a variable as parameter             // when an array is required instead             Array.setDouble(b, 5, c);         }         catch (Exception e) {             System.out.println("Exception : " + e);         }     } }
Output:

Exception : java.lang.IllegalArgumentException: Argument is not an array