Java - Final Exam
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Decrement Operator
%=
Divides a variable by the value of the right operand and assigns the remainder to the variable.
/=
Divides left operand by the right and assigns the value to the left operand.
Length
Each array in Java has a public field named ____ that contains the number of elements in the array.
Iteration
Each repetition of a loop is known as what?
Infinite loop
If a loop does not contain within itself a way to terminate, its called an _____.
0 though 14
If final int SIZE = 15 and int[] x = new int[SIZE], what would be the range of subscript values that count be used with x[]?
Information hiding
In Java, the concept of keeping data private is known as______.
String myString = "Whatever"; or String myString = newString("Whatever");
Java code to declare a variable of type String and initialize it to "whatever".
double dArray[] = new double[497];
Java code to declare and allocate an array with 497 elements of type double.
Array Bounds Checking
Java performs _____, which means that it does not allow a statement to use a subscript that is outside the range of valid subscripts for the array.
int array[][] = new int[4][5];
Java statement that declares and allocates a 2-dimensional array of integers with four rows and five columns.
-+
Subtracts right operand from the left and assigns the result the left.
PrintF
System.out.printf("it is an integer: %d%n", 1000");
Protected
The code is accessible in the same package and subclasses.
Private
The code is only accessible within the declared class.
Java API
The exception classes are in packages in the _____.
Java Virtual Machine
a program that executes compiled java code on a specific platform.
UML Diagram
Arrows used in a ____ to show inheritance relationships extend from the descendant class and point to the original class.
Data Type
By convention, a class diagram contains the _____ following each attribute or method.
Non-Static
Can access any static method and static variable, without creating an instance of the object
MyClass myObject = new MyClass("Hello");
Code to create an object named myObject by instantiating a class called MyClass and passing the constructor a String literal "hello" as the argument.
>
Greater Than
Polymorphism
In Java, using the same method name to indicate different implementations is called ______.
I
In a multi-catch, the exception types are separated in the catch clause by this symbol:
++
Increment Operator
<
Less Than
=<
Less than or equal to
*=
Multiply AND. Multiplies left operand by right and assigns product to left operand.
int iArray[] = {97, 33, 44, 12}
Show one line of Java code that declares, allocates, and initializes an array of type integer with exactly 4 elements whose values are 97, 33, 44, and 12, in that order.
Extends
The Java keyword that creates inheritance is______.
Data Type, Variable Name, Initial Value, Semicolon
The Java variable declaration creates a new variable with required properties. The programming language requires four basic things to declare a variable in a program.
Base
The class used as a basis for inheritance is the ____ class.
Subscript
What do you call the number that is used as an index to pinpoint a specific element within an array?
Object-oriented
What type of language is Java
Run-time
When a java program throws an exception because it cannot open a file.
Default
When no access modifier is specified for a class, method, or data member.
import java.io.*;
When using the PrintWriter class, which of the following import statements would you write near the top of your program?
Dog/Poodle
Which of the following choices is the best example of a parent class/child class relationship?
Extends
You use the keyboard ____ to achieve inheritance in Java.
Subtype
_____ polymorphism is the ability of one method to work appropriately for subclasses of the same parent class.
Super Class
a general class and the subclass are the specialized class
Constructor
is a block of code that initializes the newly created object. It resembles an instance method but it's not a method as it doesn't have a return type.
Inheritance
is a mechanism that enables one class to acquire all the behaviors and attributes of another class.
Println
public class HelloWorld{ public static void main(String[] args) { System.out.println("\nHello World"); } }
public void print(String s)
Event Driven Programming
when a program is designed to respond to user engagement in various forms. It is known as a program paradigm in which the flow of program execustion is determined by "events". Events are any user interaction, such as a click or key press, in response to prompt from the system.
for (int i = 0; i < iArray.length; i++) { iAverage += iArray[i]; } iAverage /= iArray.length
A loop that computes the average of an array of integers called iArray that has been previously declared and initialized. Store the result in a variable type integer called iAverage that has been previously declared and initalized to zero.
Ragged Array
A two-dimensional array where the rows are of different lengths
Search Algorithm
A way to locate a specific item in a larger collection of data.
+=
Add AND adds right operand to the left and assigns the result to the left.
Public
Functions and variables can be accessed by all parties within and outside the contract.
=>
Greater than or equal to
Finally
The try statement may have an optional ____ clause, which must appear after all of the catch clauses.
Static
They are convienient for many tasks because they can be called directly from the class, as needed. They are most often used to create a utility class that perform operations on data, but have no need to collect and store data.
Loop
This is a control structure that causes a statement or group of statements to repeat.
Exception Handler
This is a section of code that gracefully responds to exceptions when they are thrown.
Sentinel
This is a value that signals when the end of a list of values has been reached.
Post-test loop
This type of loop will always be executed at least once.
Loop Control Variable
This variable controls the number of times that the loop iterates.
Scanner
To create an object of a scanner class, we usually pass the predefined object. System.in, which represents the standard input stream. We may pass an object of a class file if we want to read input from a file. Example: Scanner input = new Scanner(System.in);
Constant
To make any variable a constant, we must use 'static' and 'final modifiers in the following manner: static final datatype identifer_name = constant;
Override
Sometimes the superclass data fields and methods are not entirely appropriate for the subclass objects; in these cases, you want to ____ the parent class members.
0
Subscript numbering always starts at what value?
Three
When you create parent and child classes of your own, the child classes use ____ constructors.
Information hiding
When you employ _____, your data can be altered only by the methods you choose and only in ways that you can control.
import java.io.File; import java.util.Scanner; public class ReadFromFileUsingScanner { public static void main(String[] args) throws exception { File file = new File("C:\\Users\\Katelyn\\Desktop\\Test.txt"); Scanner sc = new Scanner(file); while (sc.hasNextLine()) System.out.println(sc.nextLine()); } }
Write Java Statement to open a textfile for reading
ClassName object = new ClassName();
Write a Java statement to create an object:
Final
You can use the ____ modifier with methods when you don't want the method to be overridden.
Inline
A compiler can decide to _____ a final method; that is, determine the code of the method call when the program is compiled.
