Java: Interfaces
Quick summary
Interfaces:
- Interfaces can’t be instantiated
- Interfaces have methods with no bodies (no {})
- Subclasses implement interfaces (as many as they want)
- Subclasses must implement all the interface’s methods
- Interfaces standardize methods and fields for all subclasses
- All fields are final static
- The default access for an interface is protected
- The default access for an interface’s methods is public
Eclipse example: Interfaces
Detailed description
An interface is a class that has methods with no bodies. It is intended to be implemented by another class that will insert their own values for the methods. It’s a way of formalizing a class that will have a lot of subclasses, when you want all the subclasses to standardize on common strings and methods.
About Tom Johnson
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