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Should an interface extend another interface?
An interface may not implement any other interface. It can only extend it.
How does an interface inherit other interfaces?
But unlike classes, interfaces can actually inherit from multiple interfaces. This is done by listing the names of all interfaces to inherit from, separated by comma. A class implementing an interface which inherits from multiple interfaces must implement all methods from the interface and its parent interfaces.
Can we extend two interfaces?
An interface can extend multiple interfaces. A class can implement multiple interfaces. However, a class can only extend a single class. Careful how you use the words extends and implements when talking about interface and class .
How are interfaces and inheritance related in Java?
A class can extends another class and/ can implement one and more than one interface. Interface inheritance : An Interface can extend other interface. An interface can also extend multiple interfaces.
Can a interface be an extension of another interface?
Answer is: Yes. An interface may be declared to be a direct extension of one or more other interfaces, meaning that it implicitly specifies all the member types, abstract methods, and constants of the interfaces it extends, except for any member types and constants that it may hide.
When do interfaces have implementations of methods in Java?
From Java 8, interfaces also have implementations of methods. So if a class implementing two or more interfaces having the same method signature with implementation, it is mandated to implement the method in class also. Refer Java and Multiple Inheritance for details. This article is contributed by Nitsdheerendra.
Can a Java interface extend more than one parent class?
A Java class can only extend one parent class. Multiple inheritance is not allowed. Interfaces are not classes, however, and an interface can extend more than one parent interface. I think your confusion lies with multiple inheritance, in which it is bad practise to do so and in Java this is also not possible.