Java - Language Fundamentals
Java - Language Fundamentals
1. Which four options describe the correct default values for array elements of the types indicated?
int -> 0
String -> "null"
Dog -> null
char -> '\u0000'
float -> 0.0f
boolean -> true
int -> 0
String -> "null"
Dog -> null
char -> '\u0000'
float -> 0.0f
boolean -> true
- 1, 2, 3, 4
- 1, 3, 4, 5
- 2, 4, 5, 6
- 3, 4, 5, 6
2. Which one of these lists contains only Java programming language keywords?
- class, if, void, long, Int, continue
- goto, instanceof, native, finally, default, throws
- try, virtual, throw, final, volatile, transient
- byte, break, assert, switch, include
3. Which will legally declare, construct, and initialize an array?
- int [] myList = {"1", "2", "3"};
- int [] myList = (5, 8, 2);
- int myList [] [] = {4,9,7,0};
- int myList [] = {4, 3, 7};
4. Which is a reserved word in the Java programming language?
- method
- native
- subclasses
- reference
6. Which three are legal array declarations?
int [] myScores [];
char [] myChars;
int [6] myScores;
Dog myDogs [];
Dog myDogs [7];
int [] myScores [];
char [] myChars;
int [6] myScores;
Dog myDogs [];
Dog myDogs [7];
- 1, 2, 4
- 2, 4, 5
- 2, 3, 4
- All are correct.
7. public interface Foo
{
int k = 4; /* Line 3 */
}
Which three piece of codes are equivalent to line 3?
final int k = 4;
public int k = 4;
static int k = 4;
abstract int k = 4;
volatile int k = 4;
protected int k = 4;
{
int k = 4; /* Line 3 */
}
Which three piece of codes are equivalent to line 3?
final int k = 4;
public int k = 4;
static int k = 4;
abstract int k = 4;
volatile int k = 4;
protected int k = 4;
- 1, 2 and 3
- 2, 3 and 4
- 3, 4 and 5
- 4, 5 and 6
8. Which one of the following will declare an array and initialize it with five numbers?
- Array a = new Array(5);
- int [] a = {23,22,21,20,19};
- int a [] = new int[5];
- int [5] array;
9. Which three are valid declarations of a char?
char c1 = 064770;
char c2 = 'face';
char c3 = 0xbeef;
char c4 = \u0022;
char c5 = '\iface';
char c6 = '\uface';
char c1 = 064770;
char c2 = 'face';
char c3 = 0xbeef;
char c4 = \u0022;
char c5 = '\iface';
char c6 = '\uface';
- 1, 2, 4
- 1, 3, 6
- 3, 5
- 5 only
10. Which is the valid declarations within an interface definition?
- public double methoda();
- public final double methoda();
- static void methoda(double d1);
- protected void methoda(double d1);