Given:
1. abstract class Shape {
2. Shape ( ) { System.out.println ("Shape"); }
3. protected void area ( ) { System.out.println ("Shape"); }
4. }
5.
6. class Square extends Shape {
7. int side;
8. Square int side {
9./* insert code here */
10. this.side = side;
11. }
12. public void area ( ) { System.out.println ("Square"); }
13. }
14. class Rectangle extends Square {
15. int len, br;
16. Rectangle (int x, int y) {
17. /* insert code here */
18. len = x, br = y;
19. }
20. void area ( ) { System.out.println ("Rectangle"); }
21. }
Which two modifications enable the code to compile?
You want to create a singleton class by using the Singleton design pattern.
Which two statements enforce the singleton nature of the design? (Choose two.)
public class StringReplace {
public static void main(String[] args) {
String message = "Hi everyone!";
System.out.println("message = " + message.replace("e", "X")); }
}
What is the result?
Given the code fragments:
class Employee {
Optional<Address> address;
Employee (Optional<Address> address) {
this.address = address;
}
public Optional<Address> getAddress() { return address; }
}
class Address {
String city = "New York";
public String getCity { return city: }
public String toString() {
return city;
}
}
and
Address address = null;
Optional<Address> addrs1 = Optional.ofNullable (address);
Employee e1 = new Employee (addrs1);
String eAddress = (addrs1.isPresent()) ? addrs1.get().getCity() : "City Not available";
What is the result?
The protected modifier on a Field declaration within a public class means that the field ______________.
