Java Core Java - Technical Questions and Answers

121.	To what value is a variable of the String type automatically initialized?
	Answer: The default value of an String type is null. Workspace Report errors ... Name : Email: View Answer

122.	What is the difference between a field variable and a local variable?
	Answer: A field variable is a variable that is declared as a member of a class. A local variable is a variable that is declared local to a method. Workspace Report errors ... Name : Email: View Answer

123.	How are this() and super() used with constructors?
	Answer: this() is used to invoke a constructor of the same class. super() is used to invoke a superclass constructor. Workspace Report errors ... Name : Email: View Answer

124.	What does it mean that a class or member is final?
	Answer: A final class cannot be inherited. A final method cannot be overridden in a subclass. A final field cannot be changed after it's initialized, and it must include an initializer statement where it's declared. Workspace Report errors ... Name : Email: View Answer

125.	What does it mean that a method or class is abstract?
	Answer: An abstract class cannot be instantiated. Abstract methods may only be included in abstract classes. However, an abstract class is not required to have any abstract methods, though most of them do. Each subclass of an abstract class must override the abstract methods of its superclasses or it also should be declared abstract. Workspace Report errors ... Name : Email: View Answer

126.	What is a transient variable?
	Answer: Transient variable is a variable that may not be serialized. Workspace Report errors ... Name : Email: View Answer

127.	How does Java handle integer overflows and underflows?
	Answer: It uses those low order bytes of the result that can fit into the size of the type allowed by the operation. Workspace Report errors ... Name : Email: View Answer

128.	What is the difference between the >> and >>> operators?
	Answer: The >> operator carries the sign bit when shifting right. The >>> zero-fills bits that have been shifted out. Workspace Report errors ... Name : Email: View Answer

129.	Is sizeof a keyword?
	Answer: The sizeof operator is not a keyword. Workspace Report errors ... Name : Email: View Answer

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