Answer: Option B
Explanation:
(1), (3), (4), (5) are the correct statements.
(2) is wrong because the default value for a String (and any other object reference) is null, with no quotes.
(6) is wrong because the default value for boolean elements is false.
2. | Which one of these lists contains only Java programming language keywords? |
A. | class, if, void, long, Int, continue |
B. |
goto, instanceof, native, finally, default, throws | |
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C. | try, virtual, throw, final, volatile, transient |
D. | strictfp, constant, super, implements, do |
E. | byte, break, assert, switch, include |
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Answer: Option B
Explanation:
All the words in option B are among the 49 Java keywords. Although goto reserved as a keyword in Java, goto is not used and has no function.
Option A is wrong because the keyword for the primitive int starts with a lowercase i.
Option C is wrong because "virtual" is a keyword in C++, but not Java.
Option D is wrong because "constant" is not a keyword. Constants in Java are marked static and final.
Option E is wrong because "include" is a keyword in C, but not in Java.
3. | Which will legally declare, construct, and initialize an array? |
A. | int [] myList = {"1", "2", "3"}; |
B. | int [] myList = (5, 8, 2); |
C. | int myList [] [] = {4,9,7,0}; |
D. |
int myList [] = {4, 3, 7}; |
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Answer: Option D
Explanation:
The only legal array declaration and assignment statement is Option D
Option A is wrong because it initializes an int array with String literals.
Option B is wrong because it use something other than curly braces for the initialization.
Option C is wrong because it provides initial values for only one dimension, although the declared array is a two-dimensional array.
4. | Which is a reserved word in the Java programming language? |
A. | method | B. |
native | |
|
C. | subclasses | D. | reference |
E. | array |
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Answer: Option B
Explanation:
The word "native" is a valid keyword, used to modify a method declaration.
Option A, D and E are not keywords. Option C is wrong because the keyword for subclassing in Java is extends, not 'subclasses'.
5. | Which is a valid keyword in java? |
A. |
interface | |
| B. | string |
C. | Float | D. | unsigned |
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Answer: Option A
Explanation:
interface is a valid keyword.
Option B is wrong because although "String" is a class type in Java, "string" is not a keyword.
Option C is wrong because "Float" is a class type. The keyword for the Java primitive is float.
Option D is wrong because "unsigned" is a keyword in C/C++ but not in Java.
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