Autoboxing Unboxing
1.What is autoboxing in Java?
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A. The automatic conversion of a primitive type to its corresponding wrapper class object.
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B. The automatic conversion of a wrapper class object to its corresponding primitive type.
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C. The manual conversion of a primitive type to a wrapper class object.
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D. The manual conversion of a wrapper class object to a primitive type.
The automatic conversion of a primitive type to its corresponding wrapper class object.
The automatic conversion of a primitive type to its corresponding wrapper class object.
2.Which of the following scenarios demonstrates unboxing?
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A. Integer obj = 10;
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B. int i = new Integer(50);
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C. String s = "hello";
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D. double d = 3.14;
int i = new Integer(50);
int i = new Integer(50);
3.What potential issue can arise due to autoboxing/unboxing, particularly with null values?
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A. StackOverflowError
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B. NullPointerException
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C. ArrayIndexOutOfBoundsException
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D. ClassCastException
NullPointerException
NullPointerException
4.Which Java version introduced autoboxing and unboxing?
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A. Java 1.0
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B. Java 1.2
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C. Java 5
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D. Java 8
Java 5
Java 5
5.Considering the following code, what will be the output?
Integer i1 = 100;
Integer i2 = 100;
Integer i3 = 200;
Integer i4 = 200;
System.out.println(i1 == i2);
System.out.println(i3 == i4);
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A. true, true
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B. true, false
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C. false, true
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D. false, false
true, false
true, false