SCJP Questions 21-30

Question 21
Given:
11. public abstract class Shape {
12. int x;
13. int y;
14. public abstract void draw();
15. public void setAnchor(int x, int y) {
16. this.x = x;
17. this.y = y;
18. }
19. }
and a class Circle that extends and fully implements the Shape class.
Which is correct?
A. Shape s = new Shape();
s.setAnchor(10,10);
s.draw();
B. Circle c = new Shape();
c.setAnchor(10,10);
c.draw();
C. Shape s = new Circle();
s.setAnchor(10,10);
s.draw();
D. Shape s = new Circle();
s->setAnchor(10,10);
s->draw();
E. Circle c = new Circle();
c.Shape.setAnchor(10,10);
c.Shape.draw();
Answer: C

Question 22
Given:
10. abstract public class Employee {
11. protected abstract double getSalesAmount();
12. public double getCommision() {
13. return getSalesAmount() * 0.15;
14. }
15. }
16. class Sales extends Employee {
17. // insert method here
18. }
Which two methods, inserted independently at line 17, correctly
complete the Sales class? (Choose two.)
A. double getSalesAmount() { return 1230.45; }
B. public double getSalesAmount() { return 1230.45; }
C. private double getSalesAmount() { return 1230.45; }
D. protected double getSalesAmount() { return 1230.45; }
Answer: BD

Question 23
Given:
10. interface Data { public void load(); }
11. abstract class Info { public abstract void load(); }
Which class correctly uses the Data interface and Info class?
A. public class Employee extends Info implements Data {
public void load() { /*do something*/ }
}
B. public class Employee implements Info extends Data {
public void load() { /*do something*/ }
}
C. public class Employee extends Info implements Data {
public void load() { /*do something */ }
public void Info.load() { /*do something*/ }
}
D. public class Employee implements Info extends Data {
public void Data.load() { /*d something */ }
public void load() { /*do something */ }
}
E. public class Employee implements Info extends Data {
public void load() { /*do something */ }
public void Info.load(){ /*do something*/ }
}
F. public class Employee extends Info implements Data{
public void Data.load() { /*do something*/ }
public void Info.load() { /*do something*/ }
}
Answer: A

Question 24
Given:
11. public abstract class Shape {
12. private int x;
13. private int y;
14. public abstract void draw();
15. public void setAnchor(int x, int y) {
16. this.x = x;
17. this.y = y;
18. }
19. }
Which two classes use the Shape class correctly? (Choose two.)
A. public class Circle implements Shape {
private int radius;
}
B. public abstract class Circle extends Shape {
private int radius;
}
C. public class Circle extends Shape {
private int radius;
public void draw();
}
D. public abstract class Circle implements Shape {
private int radius;
public void draw();
}
E. public class Circle extends Shape {
private int radius;
public void draw() {/* code here */}
}
F. public abstract class Circle implements Shape {
private int radius;
public void draw() { / code here */ }
}
Answer: BE

Question 25
Which two classes correctly implement both the java.lang.Runnable
and the java.lang.Clonable interfaces? (Choose two.)
A. public class Session
implements Runnable, Clonable {
public void run();
public Object clone();
}
B. public class Session
extends Runnable, Clonable {
public void run() { / do something */ }
public Object clone() { / make a copy */ }
}
C. public class Session
implements Runnable, Clonable {
public void run() { / do something */ }
public Object clone() { /* make a copy */ }
}
D. public abstract class Session
implements Runnable, Clonable {
public void run() { / do something */ }
public Object clone() { /*make a copy */ }
}
E. public class Session
implements Runnable, implements Clonable {
public void run() { / do something */ }
public Object clone() { / make a copy */ }
}
Answer: CD

Question26
Click the Exhibit button.
1. public class GoTest {
2. public static void main(String[] args) {
3. Sente a = new Sente(); a.go();
4. Goban b = new Goban(); b.go();
5. Stone c = new Stone(); c.go();
6. }
7. }
8.
9. class Sente implements Go {
10. public void go() { System.out.println(”go in Sente.”); }
11. }
12.
13. class Goban extends Sente {
14. public void go() { System.out.println(”go in Goban”); }
15. }
16.
17. class Stone extends Goban implements Go { }
18.
19. interface Go { public void go(); }
What is the result?
A. go in Goban
go in Sente
go in Sente
B. go in Sente
go in Sente
go in Goban
C. go in Sente
go in Goban
go in Goban
D. go in Goban
go in Goban
go in Sente
E. Compilation fails because of an error in line 17.
Answer: C

Question 27
Given:
11. public static void parse(String str) {
12. try {
13. float f= Float.parseFloat(str);
14. } catch (NumberFormatException nfe) {
15. f= 0;
16. } finally {
17. System.out.println(f);
18. }
19. }
20. public static void main(String[] args) {
21. parse(”invalid”);
22. }
What is the result?
A. 0.0
B. Compilation fails.
C. A ParseException is thrown by the parse method at runtime.
D. A NumberFormatException is thrown by the parse method at
runtime.
Answer: B

Question 28
Click the Exhibit button.
1. public class Test {
2. int x= 12;
3. public void method(int x) {
4. x+=x;
5. System.out.println(x);
6. }
7. }
Given:
34. Test t = new Test();
35. t.method(5);
What is the output from line 5 of the Test class?
A. 5
B. 10
C. 12
D. 17
E. 24
Answer: B

Question 29
Given:
55. int []x= {1, 2,3,4, 5};
56.int y[] =x;
57. System.out.println(y[2]);
Which is true?
A. Line 57 will print the value 2.
B. Line 57 will print the value 3.
C. Compilation will fail because of an error in line 55.
D. Compilation will fail because of an error in line 56.
Answer: B

Question 30
Given:
35. String #name = “Jane Doe”;
36.int$age=24;
37. Double_height = 123.5;
38. double~temp = 37.5;
Which two are true? (Choose two.)
A. Line 35 will not compile.
B. Line 36 will not compile.
C. Line 37 will not compile.
D. Line 38 will not compile.
Answer: AD

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