Java抽象類別和介面

Apr 11, 2012

Java抽象類別與介面以及它們的差異。

Abstract class

• Can have both abstract and concrete methods;
• A class can extend only one abstract class;
• Can have protected, public and public abstract methods;
• Can have static, final, or static final variables with any access modifier;
• "is-a" relationship;
• Cannot be instantiated;

Interface

• Can have only abstract methods;
• A class can implement multiple interfaces;
• Can have only public abstract methods;
• Can have only static final (constant) variables;
• "like-a" relationship;
• Can extend another interface;

參考文獻

• Details on Difference between Java Abstract Class and Interface
• Difference Between Abstract Class and Interface in Java
• Abstract Classes and Methods in Java
• Interface in java with example programs

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