Job interview questions (Java Basics interview)

1 , what are the aspects of object-oriented features ?

　　The object-oriented programming language has 4 main features: encapsulation, inheritance, abstraction, polymorphism, etc.

Details:http://www.cnblogs.com/guweiwei/p/6599289.html

2 , access modifiers public,private,protected, and what is the difference between not writing (the default)?

　　Defaults to default when members of a class do not write access adornments. The default is equivalent to exposing (public) to other classes in the same package, and for other classes that are not in the same package are equivalent to private (private). A protected (protected) subclass is equivalent to exposing a class that is not a parent-child relationship in the same package as private.

Summarize the following table

3 , String is the most basic type of data? ?

4 , float f=3.4; is correct ?

5 , Short s1 = 1; s1 = s1 + 1; Is it wrong? ? short S1 = 1; s1 + = 1; Is it wrong? ?

6 , Java have goto?

7 , int and the Integer What's the difference? ?

8 , & and the && the difference?

9 , explaining the in-memory stack ( Stack ), Heap (heap) and the use of static storage areas.

Ten , Math.Round (11.5) equal to how much ? Math.Round ( -11.5) equals how much ?

Job interview questions (Java Basics interview)