Why do we need to implement interfaces to provide certain functionality instead of just defining the methods without implementing the interface?
31730
Why do we use Interface? Is it only for Standardization?
105030
When to use: Java 8+ interface default method, vs. abstract method
113976
Methods visibility in interface
27045
Why is method overloading and overriding needed in java?
55032
Why do I need an IoC container as opposed to straightforward DI code?
150881
implicit vs explicit interface implementation
112492
Why is there no multiple inheritance in Java, but implementing multiple interfaces is allowed?
7323
What is the point of interfaces in PHP?
41552
Do interfaces inherit from Object class in java
81041
Why an abstract class implementing an interface can miss the declaration/implementation of one of the interface's methods?
69939
Implement an interface and override methods in Java?
855
What does it mean to "program to an interface"?
80633
Java - declaring from Interface type instead of Class
152816
Abstract base classes that implement an interface
154776
When should we implement Serializable interface?
27078
When do Java generics require  instead of  and is there any downside of switching?
88182
Traits vs. interfaces