Tech Elevator Technical Interview Topics
UPDATED Exam Questions and
CORRECT Answers
Parameter - CORRECT ANSWER - Refers to the list of variables in a method declaration.
Each parameter must have a unique name and a defined data type.
What does a "JOIN" clause do? - CORRECT ANSWER - A JOIN clause is used to
combine rows from two or more tables, based on a related column between them.
Argument - CORRECT ANSWER - are the actual values that are passed in when the
method is invoked. When you invoke a method, the arguments used must match the declaration's
parameters in type and order.
What is the difference between an absolute path and a relative path? - CORRECT
ANSWER - absolute path: is specifying the location of a file or directory from the root
directory(/). In other words, we can say that an absolute path is a complete path from start of
actual file system from / directory.
Relative path is defined as the path related to the present working directly(pwd).
Class - CORRECT ANSWER - A class is a non-primitive or user-defined data type in Java
& the entire Java is built because class defines the nature of an object.
Object - CORRECT ANSWER - object: is an instance of a class. You can create many
objects from the same class type.
It stores its state in fields (variables) & exposes its behavior through methods (functions)
,Method - CORRECT ANSWER - method: a block of code that performs a specific task
What keyword do you use to inherit from a class in Java? - CORRECT ANSWER - the
"extends" keyword
What is the keyword "super" a reference to? - CORRECT ANSWER - The super keyword
refers to superclass (parent) objects. It's used to call superclass methods, and to access the
superclass constructor. The most common use of the super keyword is to eliminate the confusion
between superclasses and subclasses that have methods with the same name.
What is the "this" keyword used for in Java? - CORRECT ANSWER - The most common
use of the this keyword is to eliminate the confusion between class attributes and parameters
with the same name (because a class attribute is shadowed by a method or constructor
parameter).
this can also be used to:
- Invoke current class constructor
- Invoke current class method
- Return the current class object
- Pass an argument in the method call
- Pass an argument in the constructor call
Difference between overloading & method overriding - CORRECT ANSWER -
overloading: when two or more methods in the same class have the same name but different
parameters
Overriding: when the method signature (name and parameters) are the same in the superclass and
the child class
When/why would you overload a method? - CORRECT ANSWER - You use the same
method name but make it available with a different number of parameters. You use it to take a
, piece of functionality like some method in your object or class & call it differently depending on
the parameters passed.
A good example is string functions. By providing different parameters you can call the method
for similar but different results.
How can we share methods between unrelated classes? - CORRECT ANSWER -
Relationship between Classes & Objects - CORRECT ANSWER - A class acts as a blue-
print that defines the properties, states, and behaviors that are common to a number of objects.
An object is an instance of the class.
For example, suppose Bicycle is a class then Mountain Bicycle, Sports Bicycle, Touring Bicycle,
would be considered as objects of the class.
Difference between a constructor & method - CORRECT ANSWER - A Constructor is a
block of code that initializes a newly created object. It can be used to initialize an object & it's
invoked implicitly by the system. A Constructor's name has to be the same as the name of the
class, & a Constructor cannot be inherited by subclasses.
A Method is a collection of statements which returns a value during its execution. A method
consists of Java code to be executed by the programmer. A Method's name can be anything & it
can be inherited by subclasses.
What is the difference between an array & other collection types? - CORRECT
ANSWER -
Difference between "for" & "while" loops - CORRECT ANSWER - For loop: used to
iterate over an array & you use a for loop when you know the loop should execute a certain
number of times.
UPDATED Exam Questions and
CORRECT Answers
Parameter - CORRECT ANSWER - Refers to the list of variables in a method declaration.
Each parameter must have a unique name and a defined data type.
What does a "JOIN" clause do? - CORRECT ANSWER - A JOIN clause is used to
combine rows from two or more tables, based on a related column between them.
Argument - CORRECT ANSWER - are the actual values that are passed in when the
method is invoked. When you invoke a method, the arguments used must match the declaration's
parameters in type and order.
What is the difference between an absolute path and a relative path? - CORRECT
ANSWER - absolute path: is specifying the location of a file or directory from the root
directory(/). In other words, we can say that an absolute path is a complete path from start of
actual file system from / directory.
Relative path is defined as the path related to the present working directly(pwd).
Class - CORRECT ANSWER - A class is a non-primitive or user-defined data type in Java
& the entire Java is built because class defines the nature of an object.
Object - CORRECT ANSWER - object: is an instance of a class. You can create many
objects from the same class type.
It stores its state in fields (variables) & exposes its behavior through methods (functions)
,Method - CORRECT ANSWER - method: a block of code that performs a specific task
What keyword do you use to inherit from a class in Java? - CORRECT ANSWER - the
"extends" keyword
What is the keyword "super" a reference to? - CORRECT ANSWER - The super keyword
refers to superclass (parent) objects. It's used to call superclass methods, and to access the
superclass constructor. The most common use of the super keyword is to eliminate the confusion
between superclasses and subclasses that have methods with the same name.
What is the "this" keyword used for in Java? - CORRECT ANSWER - The most common
use of the this keyword is to eliminate the confusion between class attributes and parameters
with the same name (because a class attribute is shadowed by a method or constructor
parameter).
this can also be used to:
- Invoke current class constructor
- Invoke current class method
- Return the current class object
- Pass an argument in the method call
- Pass an argument in the constructor call
Difference between overloading & method overriding - CORRECT ANSWER -
overloading: when two or more methods in the same class have the same name but different
parameters
Overriding: when the method signature (name and parameters) are the same in the superclass and
the child class
When/why would you overload a method? - CORRECT ANSWER - You use the same
method name but make it available with a different number of parameters. You use it to take a
, piece of functionality like some method in your object or class & call it differently depending on
the parameters passed.
A good example is string functions. By providing different parameters you can call the method
for similar but different results.
How can we share methods between unrelated classes? - CORRECT ANSWER -
Relationship between Classes & Objects - CORRECT ANSWER - A class acts as a blue-
print that defines the properties, states, and behaviors that are common to a number of objects.
An object is an instance of the class.
For example, suppose Bicycle is a class then Mountain Bicycle, Sports Bicycle, Touring Bicycle,
would be considered as objects of the class.
Difference between a constructor & method - CORRECT ANSWER - A Constructor is a
block of code that initializes a newly created object. It can be used to initialize an object & it's
invoked implicitly by the system. A Constructor's name has to be the same as the name of the
class, & a Constructor cannot be inherited by subclasses.
A Method is a collection of statements which returns a value during its execution. A method
consists of Java code to be executed by the programmer. A Method's name can be anything & it
can be inherited by subclasses.
What is the difference between an array & other collection types? - CORRECT
ANSWER -
Difference between "for" & "while" loops - CORRECT ANSWER - For loop: used to
iterate over an array & you use a for loop when you know the loop should execute a certain
number of times.
