Classic Questions (1)

1. Can the constructor Constructor be override?

A: The constructor Constructor cannot be inherited, so overriding cannot be overridden, but can be re-

Load overloading.

2.

Two object values are the same (x.equals (y) = = true), but can have different hash code, which

A sentence, right?

Answer: No, there is the same hash code.

3.

Can I inherit the String class?

A: The String class is the final class and therefore cannot be inherited.

4.

The following two statements return a value of true:

A: "Beijing" = = "Beijing";

B: "Beijing". Equalsignorecase (New String ("Beijing"));

Answer: A and B.

5.

When an object is passed as a parameter to a method, this method can change the properties of the object.

And can return the result of the change, so is it a value pass or a reference pass?

A: The value is passed. The Java programming language has only value-passing parameters. When an object instance is used as a parameter

When passed to a method, the value of the parameter is a reference to the object. The contents of the object can be called in the

method, but the object's reference is never changed.

Classic Questions (1)