Possible Duplicate:
Interface vs Base class
A class implementing an interface has to implement all the methods of the interface, but if that class is implementing an abstract class is it necessary to implement all abstract methods?
If not, can we create the object of that class which is implementing the Abstract class???
如果你执行一个抽象的类别,不执行所有抽象的方法,那么这一类别也必须宣布为抽象的,因此不能立即进行。
例如:
public abstract class A {
public abstract method1();
}
public abstract class B extends A {
}
在上述例子中,您无法打电话new B();。
如果某一阶层继承一个抽象的类别,它要么必须执行所有抽象成员,要么也必须是抽象的。
因此,如果这个班子不执行所有成员,你就能够树立榜样。
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