Quick Answer
Interface: defines a contract (method signatures), no instance fields (only constants), a class can implement multiple interfaces, methods are public abstract by default (Java 8+ allows default and static methods). Abstract class: can have concrete methods and instance fields, single inheritance only, use when related classes share common implementation. Choose interface for capabilities, abstract class for shared base implementation.
Answer
Interface: Only abstract methods (older Java). Abstract class: Can have concrete methods and fields. Interfaces support multiple inheritance.
S
SugharaIQ Editorial Team
Verified Answer
This answer has been peer-reviewed by industry experts holding senior engineering roles to ensure technical accuracy and relevance for modern interview standards.
