Java operator "instanceof" - Instructions and examples

In this practical tip, we will explain how you can use the instanceof operator in Java with pinpoint accuracy.

Java operator "instanceof" - Instructions and examples

Use the instanceof operator to check whether a particular object is an instance of a special class. You normally use this operator if you have a parameter or an object from an interface or a super class and you want to check whether the actual object has other types. The following code checks, for example, which parameter it is.

1. public void doSomething (Number parameter1) {
2. if (parameter1 instanceof Double) {
3. System.out.println ("The parameter is a double!");
4. } else if (parameter1 instanceof integer) {
5. System.out.println ("The parameter is an integer!"); }
6. if (parameter1 instanceof Comparable) {
7. System.out.println ("The parameter occurs in the Comparable Interface!"); }}

In the next practical tip, we will give you a basic introduction to the Java programming language.