MCQ's on Java Fundamentals

1. Which is a valid keyword in java?

A. interface
B. Float
C. string
D. unsigned
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A. interface

2. Which is a reserved word in the Java programming language?

A. method
B. array
C. native
D. reference
D. subclasses
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C. native

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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D. int myList [] = {4, 3, 7};

4. Which three are legal array declarations?

1. int [] myScores [];
2. char [] myChars;
3. int [6] myScores;
4. Dog myDogs [];
5. Dog myDogs [7];

A. 1,2,4
B. 2,4,5
C. 2,3,4
D. All are correct.
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A. 1,2,4

5. Which one of the following will declare an array and initialize it with five numbers?

A. Array a = new Array(5);
B. int [] a = {23,22,21,20,19};
C. int a [] = new int[5];
D. int [5] array;
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B. int [] a = {23,22,21,20,19};

6. Which three are valid declarations of a char?
1. char c1 = 064770;
2. char c2 = 'face';
3. char c3 = 0xbeef;
4. char c4 = \u0022;
5. char c5 = '\iface';
6. char c6 = '\uface';

A. 1,2,4
B. 1,3,6
C. 3,5,2
D. 4,1,6
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B. 1,3,6

7. Which is the valid declarations within an interface definition?

A. public double methoda();
B. public final double methoda();
C. static void methoda(double d1);
D. protected void methoda(double d1);
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A. public double methoda();

8. Which one is a valid declaration of a boolean?

A. boolean b1 = 0;
B. boolean b2 = 'false';
C. boolean b3 = false;
D. boolean b4 = Boolean.false();
E. boolean b5 = no;
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B. 1,3,6

9. Which three are valid declarations of a float?

1. float f1 = -343;
2. float f2 = 3.14;
3. float f3 = 0x12345;
4. float f4 = 42e7;
5. float f5 = 2001.0D;
6. float f6 = 2.81F;

A. 1,2,4
B. 2,3,5
C. 1,3,6
D. 2,4,6
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C. 1,3,6

10. Which is a valid declarations of a String?

A. String s1 = null;
B. String s2 = 'null';
C. String s3 = (String) 'abc';
D. String s4 = (String) '\ufeed';
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A. String s1 = null;