Question

Example:

Object[] x = new Object[2];
x[0] = 3; // integer
x[1] = "4"; // String
System.out.println(x[0].getClass().getSimpleName()); // prints "Integer"
System.out.println(x[1].getClass().getSimpleName()); // prints "String"

This makes me wonder: the first object element is an instance of class Integer? or is it a primitive data type int? There is a difference, right?

So if I want to determine the type of first element (is it an integer, double, string, etc), how to do that? Do I use x[0].getClass().isInstance()? (if yes, how?), or do I use something else?

Answer 1

You want to use the instanceof operator.

for instance:

if(x[0] instanceof Integer) {
 Integer anInt = (Integer)x[0];
 // do this
} else if(x[0] instanceof String) {
 String aString = (String)x[0];
 //do this
}