Quiz 10: Interfaces

____ methods must be implemented when using an interface.

Consider the following code snippet: public class Inventory implements Measurable { ) . . Double getMeasure(); { Return onHandCount; } } The compiler complains that the getMeasure method has a weaker access level than the Measurable interface. Why?

Which of the following statements about interfaces is NOT true?

Which of the following statements about a Java interface is NOT true?

Which of the following statements about an interface is true?

Consider the following code snippet. public interface Measurable { Double getMeasure(); } Public class Coin implements Measurable { Public double getMeasure() { Return value; } ).. } Public class DataSet { ).. Public void add() { ).. } } Public class BankAccount { ).. Public void add() { ).. } } Which of the following statements is correct?

Consider the following code snippet: public class Inventory implements Measurable { ) . . Double getMeasure(); { Return onHandCount; } } What is wrong with this code?

Consider the following code snippet: public class Inventory implements Measurable { ) . . Public double getMeasure(); { Return onHandCount; } } Why is it necessary to declare getMeasure as public ?

Which of the following statements about abstract methods is true?

Consider the following declarations: public interface Encryptable { Void encrypt(String key); } Public class SecretText implements Encryptable { Private String text; _____________________________ { // code to encrypt the text using encryption key goes here } } Which of the following method headers should be used to complete the SecretText class?

To use an interface, a class header should include which of the following?

____ can reduce the coupling between classes.

Which statement about methods in an interface is true?

Suppose you are writing an interface called Resizable, which includes one void method called resize. public interface Resizable { _________________________ } Which of the following can be used to complete the interface declaration correctly?

Which of the following statements about converting between types is true?

Which of the following statements about interfaces is true?

A method that has no implementation is called a/an ____ method.

Which of the following statements about interfaces is NOT true?

Consider the following code snippet: public interface Sizable { Int LARGE_CHANGE = 100; Int SMALL_CHANGE = 20; Void changeSize(); } Which of the following statements is true?

Which of the following is true regarding a class and interface types?