Wrapper Classes
1.Which of these is NOT a wrapper class in Java?
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A. Integer
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B. Float
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C. Boolean
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D. Characterize
Characterize
Characterize
2.What is the output of the following code?
Integer x = 100;
Integer y = 100;
System.out.println(x == y);
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A. true
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B. false
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C. Compilation error
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D. Exception
true
true
3.What is Autoboxing in Java?
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A. Converting String to Integer
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B. Converting primitive to Wrapper object
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C. Converting Wrapper to primitive
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D. Converting object to primitive
Converting primitive to Wrapper object
Converting primitive to Wrapper object
4.What will this code print?
int a = 10;
Integer b = Integer.valueOf(a);
System.out.println(b);
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A. 10
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B. 0
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C. Error
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D. null
10
10
5.Which method converts a String to an int primitive?
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A. valueOf()
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B. parseInt()
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C. intValue()
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D. toString()
parseInt()
parseInt()