What Restrictions Are Placed On Method Overriding?
Overridden methods must have the same name, argument list, and return type. The overriding method may not limit the access of the method it overrides. The overriding method may not throw any exceptions that may not be thrown by the overridden method.
What Is A Java Package And How Is It Used?
A Java package is a naming context for classes and interfaces. A package is used to create a separate name space for groups of classes and interfaces. Packages are also used to organize related classes and interfaces into a single API unit and to control accessibility to these classes and interfaces.
What Modifiers May Be Used With A Top-level Class?
A top-level class may be public, abstract, or final.
What Is The Difference Between An If Statement And A Switch Statement?
The if statement is used to select among two alternatives. It uses a boolean expression to decide which alternative should be executed. The switch statement is used to select among multiple alternatives. It uses an int expression to determine which alternative should be executed.
Can A Method Be Overloaded Based On Different Return Type But Same Argument Type ?
No, because the methods can be called without using their return type in which case there is ambiquity for the compiler
What Happens To A Static Var That Is Defined Within A Method Of A Class ?
Can't do it. You'll get a compilation error
How Many Static Init Can You Have ?
As many as you want, but the static initializers and class variable initializers are executed in textual order and may not refer to class variables declared in the class whose declarations appear textually after the use, even though these class variables are in scope.
What Is The Difference Between Method Overriding And Overloading?
Overriding is a method with the same name and arguments as in a parent, whereas overloading is the same method name but different arguments
What Is Constructor Chaining And How Is It Achieved In Java ?
A child object constructor always first needs to construct its parent (which in turn calls its parent constructor.). In Java it is done via an implicit call to the no-args constructor as the first statement.
What Is The Difference Between The Boolean & Operator And The && Operator?
If an expression involving the Boolean & operator is evaluated, both operands are evaluated. Then the & operator is applied to the operand. When an expression involving the && operator is evaluated, the first operand is evaluated. If the first operand returns a value of true then the second operand is evaluated. The && operator is then applied to the first and second operands. If the first operand evaluates to false, the evaluation of the second operand is skipped.
Which Java Operator Is Right Associative?
The = operator is right associative.
Can A Double Value Be Cast To A Byte?
Yes, a double value can be cast to a byte.
What Is The Difference Between A Break Statement And A Continue Statement?
A break statement results in the termination of the statement to which it applies (switch, for, do, or while). A continue statement is used to end the current loop iteration and return control to the loop statement.
Can A For Statement Loop Indefinitely?
Yes, a for statement can loop indefinitely. For example, consider the following: for(;;) ;
To What Value Is A Variable Of The String Type Automatically Initialized?
The default value of an String type is null.
What Is The Difference Between A Field Variable And A Local Variable?
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.
How Are This() And Super() Used With Constructors?
this() is used to invoke a constructor of the same class. super() is used to invoke a superclass constructor.
What Does It Mean That A Class Or Member Is Final?
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.
What Does It Mean That A Method Or Class Is Abstract?
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.
Can An Anonymous Class Be Declared As Implementing An Interface And Extending A Class?
An anonymous class may implement an interface or extend a superclass, but may not be declared to do both.
What Is The Catch Or Declare Rule For Method Declarations?
If a checked exception may be thrown within the body of a method, the method must either catch the exception or declare it in its throws clause.
Overridden methods must have the same name, argument list, and return type. The overriding method may not limit the access of the method it overrides. The overriding method may not throw any exceptions that may not be thrown by the overridden method.
What Is A Java Package And How Is It Used?
A Java package is a naming context for classes and interfaces. A package is used to create a separate name space for groups of classes and interfaces. Packages are also used to organize related classes and interfaces into a single API unit and to control accessibility to these classes and interfaces.
What Modifiers May Be Used With A Top-level Class?
A top-level class may be public, abstract, or final.
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| Symantec Most Frequently Asked Latest Core Java Interview Questions Answers |
What Is The Difference Between An If Statement And A Switch Statement?
The if statement is used to select among two alternatives. It uses a boolean expression to decide which alternative should be executed. The switch statement is used to select among multiple alternatives. It uses an int expression to determine which alternative should be executed.
Can A Method Be Overloaded Based On Different Return Type But Same Argument Type ?
No, because the methods can be called without using their return type in which case there is ambiquity for the compiler
What Happens To A Static Var That Is Defined Within A Method Of A Class ?
Can't do it. You'll get a compilation error
How Many Static Init Can You Have ?
As many as you want, but the static initializers and class variable initializers are executed in textual order and may not refer to class variables declared in the class whose declarations appear textually after the use, even though these class variables are in scope.
What Is The Difference Between Method Overriding And Overloading?
Overriding is a method with the same name and arguments as in a parent, whereas overloading is the same method name but different arguments
What Is Constructor Chaining And How Is It Achieved In Java ?
A child object constructor always first needs to construct its parent (which in turn calls its parent constructor.). In Java it is done via an implicit call to the no-args constructor as the first statement.
What Is The Difference Between The Boolean & Operator And The && Operator?
If an expression involving the Boolean & operator is evaluated, both operands are evaluated. Then the & operator is applied to the operand. When an expression involving the && operator is evaluated, the first operand is evaluated. If the first operand returns a value of true then the second operand is evaluated. The && operator is then applied to the first and second operands. If the first operand evaluates to false, the evaluation of the second operand is skipped.
Which Java Operator Is Right Associative?
The = operator is right associative.
Can A Double Value Be Cast To A Byte?
Yes, a double value can be cast to a byte.
What Is The Difference Between A Break Statement And A Continue Statement?
A break statement results in the termination of the statement to which it applies (switch, for, do, or while). A continue statement is used to end the current loop iteration and return control to the loop statement.
Can A For Statement Loop Indefinitely?
Yes, a for statement can loop indefinitely. For example, consider the following: for(;;) ;
To What Value Is A Variable Of The String Type Automatically Initialized?
The default value of an String type is null.
What Is The Difference Between A Field Variable And A Local Variable?
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.
How Are This() And Super() Used With Constructors?
this() is used to invoke a constructor of the same class. super() is used to invoke a superclass constructor.
What Does It Mean That A Class Or Member Is Final?
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.
What Does It Mean That A Method Or Class Is Abstract?
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.
Can An Anonymous Class Be Declared As Implementing An Interface And Extending A Class?
An anonymous class may implement an interface or extend a superclass, but may not be declared to do both.
What Is The Catch Or Declare Rule For Method Declarations?
If a checked exception may be thrown within the body of a method, the method must either catch the exception or declare it in its throws clause.