What is the difference between extends vs implements in java

[Zeverto]

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Whats the difference between "implements" and "extends"? The class i have implemented automatically inherits all of the superclass's methods and may override any of them (except the ones defined "final") or none of them (except the ones defined "abstract"), whatever you need. I know Extend is used to subclass and Implement is used to inherit. But it isn't configuring perfectly.

[Pikachoo]

I recently did a DHTML lesson on Inheritance for the Java class that I teach. Please look at the Java Tutorial on java.sun.com for an explanation of classes and interfaces . You'll need IE4 or later as we've standardized on IE at the school and I didn't have time to make it cross-browser. Java does allow you to implement multiple interfaces.

[Otto]

Java does not allow you to extend multiple classes. This avoids some problems related to multiple inheritance, When you want to subclass from an existing class( inheritance ) you use the extends keyword. When you want to implent an interface, You can only extend one class in java, but you can implement many interfaces.

[Walter.D]

Simply put, extents is used when creating a subclass and implements is used when implementing an interface. When you "implement" a class, the parent class had nothing more than the method definitionSince java only allows for single inheritance of superclasses implementing interfaces is a way around this restriction. Interfaces are about subtyping and polymorphism, whereas, inheriting methods is about code reuse.