Kerri  Chinneck
Quiz por , criado more than 1 year ago

National Senior Certificate (Matric) Information Technology Quiz sobre OCA, criado por Kerri Chinneck em 18-03-2017.

51
2
0
Kerri  Chinneck
Criado por Kerri Chinneck mais de 7 anos atrás
Fechar

OCA

Questão 1 de 10

1

What happens when the following program is compiled and run?

public class MyData {

String name;
int i;
int i2 = 4;
int i3 = i2 / i;

public static void main(String[] args){
MyData md = new MyData();
System.out.print(md.i3);
}
}

Selecione uma das seguintes:

  • This code writes "0" to the standard output.

  • This code writes nothing to the standard output.

  • This code writes "null" to the standard output.

  • This code writes error dividing by zero to the standard output.

Explicação

Questão 2 de 10

1

What happens when the following program is compiled and run?

public class Employee {

// Primitive data types
double salary;
int age;
boolean isPaid;
char gender = 'm'; // m = male, f = female

public static void main(String[] args){
Employee emp = new Employee();
System.out.print(" " + emp.salary + ",");
System.out.print(" " + emp.age + ",");
System.out.print(" " + emp.isPaid + ",");
System.out.print(" " + emp.gender);
}
}

Selecione uma das seguintes:

  • This code writes ", , , m" to the standard output.

  • This code writes "1.0, 1, true, m" to the standard output.

  • This code writes "0.0, 0, false, m" to the standard output.

  • This code does not compile, because some of the variables are not initialized.

Explicação

Questão 3 de 10

1

What will be the result of calling the following method with an input of 2?

1. public int adder( int N ){
2. return 0x100 + N++ ;
3. }

Selecione uma das seguintes:

  • The method will return 258.

  • The method will return 102.

  • The method will return 259.

  • The method will return 103.

Explicação

Questão 4 de 10

1

What happens when you attempt to compile and run the following code?

1. public class Logic {
2. static int minusOne = -1 ;
3. static public void main(String args[] ){
4. int N = minusOne >> 31 ;
5. System.out.println("N = " + N );
6. }
7. }

Selecione uma das seguintes:

  • The program will compile and run, producing the output "N = -1".

  • The program will compile and run, producing the output "N = 1".

  • A runtime ArithmeticException will be thrown.

  • The program will compile and run, producing the output "N = 0".

Explicação

Questão 5 de 10

1

How many String objects are created in the following code?

1. String A, B, C ;
2. A = new String( "1234" ) ;
3. B = A ;
4. C = A + B ;

Selecione uma das seguintes:

  • One

  • Two

  • Three

  • Four

Explicação

Questão 6 de 10

1

Which of the following versions of initializing a char variable would cause a compiler error? [Check all correct answers.]

char c = - 1 ;
char c = '\u00FF' ;
char c = (char) 4096 ;
char c = 4096L ;
char c = 'c' ;
char c = "c" ;

Selecione uma das seguintes:

  • char c = - 1 ;

  • char c = '\u00FF' ;

  • char c = (char) 4096 ;

  • char c = 4096L ;

  • char c = 'c' ;

  • char c = "c" ;

Explicação

Questão 7 de 10

1

What happens when you try to compile and run the following code?
1. public class EqualsTest{
2. public static void main(String args[]){
3. char A = '\u0005' ;
4. if( A == 0x0005L ) {
5. System.out.println("Equal");
6. }
7. else {
8. System.out.println("Not Equal");
9. }
10. }
11. }

Selecione uma das seguintes:

  • The compiler reports "Invalid character in input" in line 3.

  • The program compiles and prints "Not Equal".

  • The program compiles and prints "Equal".

  • The compiler objects to the use of == to compare a char and a long.

Explicação

Questão 8 de 10

1

In the following code fragment, you know that the getParameter call may return a null if there is no parameter named size:

1. int sz ;
2. public void init(){
3. sz = 10 ;
4. String tmp = getParameter("size");
5. if( tmp != null X tmp.equals("BIG"))
sz = 20 ;
6. }

Selecione uma das seguintes:

  • &

  • &&

  • |

  • ||

Explicação

Questão 9 de 10

1

What would happen if you tried to compile and run the following code?
1. public class EqualsTest{
2. public static void main(String args[]){
3. Long L = new Long( 7 );
4. if( L.equals( 7L ))
System.out.println("Equal");
5. else System.out.println("Not Equal");
6. }
7. }

Selecione uma das seguintes:

  • The program would compile and print "Equal".

  • The program would compile and print "Not Equal".

  • The compiler would object to line 4.

  • A runtime cast error would occur at line 4.

Explicação

Questão 10 de 10

1

What would happen if you tried to compile and run the following code?
1. public class EqualsTest{
2. public static void main(String args[]){
3. Object A = new Long( 7 );
4. Long L = new Long( 7 ) ;
5. if( A.equals( L ))
System.out.println("Equal");
6. else System.out.println("Not Equal");
7. }
8. }

Selecione uma das seguintes:

  • The program would compile and print "Equal".

  • The program would compile and print "Not Equal".

  • The compiler would object to line 5.

  • A runtime cast error would occur at line 5.

Explicação