Codegrepper Java instanceof

Codegrepper Java instanceof is a powerful feature that allows you to determine whether an object is an instance of a particular class or interface. This is very useful when you need to perform different actions depending on the type of object that you are working with.

Syntax

object instanceof class/interface

Where object is the object that you want to test, and class/interface is the class or interface that you want to test against.

Example

Object obj = new Integer(100);
if (obj instanceof Integer) {
    System.out.println("Object is an instance of Integer");
} else {
    System.out.println("Object is not an instance of Integer");
}

In this example, we create a new Integer object and assign it to the obj variable. We then use the instanceof operator to test whether obj is an instance of the Integer class. Since obj is an instance of Integer, the output of this example is:

Object is an instance of Integer

Using instanceof with Interfaces

You can also use the instanceof operator to test whether an object implements a particular interface. For example:

interface MyInterface {
    void doSomething();
}

class MyClass implements MyInterface {
    public void doSomething() {
        // implementation here
    }
}

MyInterface obj = new MyClass();
if (obj instanceof MyInterface) {
    System.out.println("Object implements MyInterface");
}

In this example, we define an interface called MyInterface and a class called MyClass that implements the interface. We then create a new MyClass object and assign it to the obj variable, which is declared to be of type MyInterface. We use the instanceof operator to test whether obj implements the MyInterface interface. Since obj does implement MyInterface, the output of this example is:

Object implements MyInterface

Conclusion

Codegrepper Java instanceof is a powerful feature that can help you to write more flexible and reusable code. By using instanceof, you can determine the type of object that you are working with and perform different actions depending on its type.