MidTerm Exam Flash Cards

Question 1

What does the toString() method return?

Answer 1

It returns a String representation of the Object.

Question 2

What does the equals(otherObject) do?

Answer 2

It is a method compares an Object to otherObject and returns true if both variables reference the same object

Question 3

What is a try block?

Answer 3

Surrounds normal code, which is exited immediately if the block throws an exception

Question 4

What is a catch block?

Answer 4

A catch block catches an exception thrown in a preceding try block

Question 5

A catch block is also called…

Answer 5

An exception handler

Question 6

What is a FileNotFoundException?

Answer 6

Attempt to open a file denoted by a filename failed

Question 7

What is EOFException?

Answer 7

End of file or end of stream has been reached unexpectedly

Question 8

What is an ArrayIndexOutOfBoundsExcepton?

Answer 8

An array has been accesed with an illegal index

Question 9

What is an InputMismatchException?

Answer 9

Received input does not match expected type or the input is out of range for the expected type

Question 10

What is an ArithmeticException?

Answer 10

Arithmetic condition failed

Question 11

What does null mean?

Answer 11

null is a special value indicating a pointer points to nothing

Question 12

What is the first node called?

Answer 12

Head

Question 13

What is the last node called?

Answer 13

Tail

Question 14

What does append() mean? Where is the element added?

Answer 14

Add a new element and the tail points to the new node

Question 15

What is prepend()? Where is the element added?

Answer 15

Adds the new node before the list’s head

Question 16

How to prepend to an empty list?

Answer 16

Check if the list’s pointer head is empty.
Point the head to the new node

Question 17

How to prepend to a non-empty list?

Answer 17

Check if the head not null(not empty)
point the new node to the head node

Question 18

Removing a node:
ListRemovesAfter(numsList, node 5).
What happens to the node?

Answer 18

The node that it points to is removed

Question 19

What is removed?
ListRemoveAfter(numsList, null)

Answer 19

If the curNode is null, it removes the head node

Question 20

True or False.
If the current node is null does it remove the head?

Answer 20

True.

Question 21

Where does a search start?

Answer 21

At a lists head

Question 22

What happens when no match is found?

Answer 22

Null is returned

Question 23

When swapping 2 variables what other variable must you use?

Answer 23

A temp variable

Question 24

When reversing a list what happens?

Answer 24

The outer most elements are swapped all the way until the middle

Question 25

What does the sort() method do?

Answer 25

Sorts collections into ascending order

Question 26

True or False. An interface cannot be instantiated.

Answer 26

True.

Question 27

What is it called when you have 2 methods with the same name within a class?

Answer 27

Overloading

Question 28

What does the == operator do?

Answer 28

Checks the memory location of the 2 objects

Question 29

True or False? Primitive variables represent the value itself not the address

Answer 29

True

Question 30

When do you use the equals() method?

Answer 30

Use it to compare the objects

Question 31

What does double mean?

Answer 31

It is another method to float and integer

Question 32

When you don't know what a generic type is going to be?

Answer 32

Use in the generic to make sure it can pass anything

Question 33

What does this ++ operator do

Answer 33

It increments the value by 1

Question 34

What does -- operator do?

Answer 34

Decreases the the value of a variable by 1

Question 35

What does thus logical operator do? !

Answer 35

Reverses the result, returns false if the result is true

Question 36

What does this concat() method do?

Answer 36

It concatenates 2 strings together

Question 37

What method do you use to return the index(position) of the first occurance of "e"

Answer 37

System.out.println(txt.indexOf("e"));

Question 38

What does this += oparator do?

Answer 38

It adds to the given value in the stated variable

Question 39

What does widening Casting mean?

Answer 39

It means to convert a smaller type to a larger type

Question 40

What does narrow casting mean?

Answer 40

It means to compare a larger type to a smaller type

Question 41

Single line comments are noted with...

Answer 41

// (2 slashes)

Question 42

Multi-line comments start with...

Answer 42

/*

Question 43

Multi-line comments end with...

Answer 43

*/

Question 44

What is a subclass?

Answer 44

The child class that inherits from another class

Question 45

What is a superclass?

Answer 45

The parent class meaning the class being inherited from

Question 46

What does Polymorphism mean?

Answer 46

It means many forms and occurs when we have many classes that are related to each other by inheritance

Question 47

What does this line of code do? x = myObj.nextInt()

Answer 47

It reads the users input

Question 48

What is the Scanner class used for?

Answer 48

It is used to get user input and it is found in the java.util package

Question 49

What does the nextLine() do?

Answer 49

Reads a Strng value from the user.

Question 50

What does the nextInt() value do ?

Answer 50

It reads the int value from the user

Question 51

True or False. An exception can be thrown inside a try-catch statement and the same exception can be caught within the try-catch statement.

Answer 51

True.

Question 52

What does ADT stand for and what does it mean?

Answer 52

It stands for abstract data type and it is a collection of data along with operations that can be performed on the data

Question 53

An interface must be implemented using what keyword?

Answer 53

Implements

Question 54

What does an ADT do?

Answer 54

It specifically says what an operation does, not how it does it

Question 55

What does the push() method do?

Answer 55

It adds an element at the top of a stack

Question 56

What does the pop() method do?

Answer 56

It removes an element at the top of a stack

Question 57

What type of Structure is a stack?

Answer 57

LIFO(Last In, First Out)

Question 58

What is a stack?

Answer 58

It is a collection whose elements are added and removed from one end, called the top of the stack

Question 59

What does the peek() method do?

Answer 59

Returns the element at the top of the stack without removing it

Question 60

True or False. A stack can be empty.

Answer 60

True