1.2.3 Test
A computer program is a set of instructions that enable the computer to solve a problem or perform a task. main memory. pseudocode. a flow chart.
a set of
Because Java byte code is the same on all computers, compiled Java programs are non-existent. must be re-compiled for each different machine it is run on. are highly portable. cannot run on computers with different operating systems.
are highly portable
The data contained in an object is known as methods. attributes. classes. fields.
attributes
If you do not provide initialization values for a class's numeric fields, they will cause a runtime error. contain an unknown value. be automatically initialized with 0. cause a compiler error.
be automatically
A class's responsibilities include the things a class is responsible for knowing. the things a class is responsible for doing. both the things a class is responsible for knowing and the things a class is responsible for doing neither the things a class is responsible for knowing nor the things a class is responsible for doing
both the things a class is responsible for knowing and the things a class is responsible for doing
A Java program must have at least one comment. System.out.println(); statement. class definition. variable declaration.
class
Variables are classified according to their names. values. location in memory. data type.
data type
What will be the displayed when the following code is executed? final int x=22,y=4; y += x; System.out.println("x= " + x = 22, y = 26 x = 22, y = 4 x = 22, y = 88 Nothing. There is an error in the code.
error
Variables of the boolean data type are useful for evaluating conditions that are either true or false. working with small integers. working with very large integers. evaluating scientific notation.
evalating conditions that are either ture or false
A message dialog is a quick and simple way to ask the user to enter data. True False
false
Colons are used to indicate the end of a Java statement. True False
false
The public access specifier for a field indicates that the field may not be accessed by statements outside the class. True False
false
When a local variable in an instance method has the same name as an instance field, the instance field hides the local variable. True False
false
It is common practice in object-oriented programming to make all of a class's fields private. methods private. fields public. fields and methods public.
fields private
________ refers to the physical components that a computer is made of. Input Main memory Control unit Hardware
hardware
When an object is created, the attributes associated with the object are called instance fields. class instances. instance methods. fixed attributes.
instance field
Methods that operate on an object's fields are called instance methods. instance variables. private methods. public methods.
instance method
When saving a Java source file, save it with an extension of .java. .javac. .src. .class.
java
Suppose you are at an operating system command line, and you are going to use the following command to compile a program: javac MyClass.java Before entering the command, you must close all other Windows on your computer system. make sure you are in the same directory or folder where the MyClass.java file is located. execute the java.sun.com program. save the program with the .comp extension.
makes sure
Class objects normally have ________ that perform useful operations on their data, but primitive variables do not. fields relationships methods instances
methods
A(n) ________ is a software entity that contains data and procedures. object program class method
object
The key word new creates a new class. creates a new Java byte code file. creates an object in memory. creates a new variable in memory.
object
In the blueprint/house analogy, think of a class as a blueprint that describes a house and ________ as instances of the house built from the blueprint. methods fields objects attributes
objects
A group of related classes is called a(n) archive. package. collection. attachment.
package
This is a special language used to write computer programs. Pseudocode Operating system Application Programming language
programming
One of the design tools used by programmers when creating a model of the program is ALU. pseudocode. byte code. syntax.
pseudocode
________ are used to indicate the end of a Java statement. Periods Asterisks Semicolons Colons
semicolones
Character literals are enclosed in ________, and string literals are enclosed in ________. single quotes, double quotes double quotes, single quotes single quotes, single quotes double quotes, double quotes
single, double
Which of the following is not a rule that must be followed when naming identifiers? After the first character, you may use the letters a-z, A-Z, an underscore, a dollar sign, or digits 0-9. Identifiers can contain spaces. Uppercase and lowercase characters are distinct. The first character must be one of the letters a-z, A-Z, an underscore or a dollar sign.
spaces
You should not define a class field that is dependent upon the values of other class fields in order to keep it current. because it is redundant. in order to avoid having stale data. because it should be defined in another class.
stale data
Variables are symbolic names made up by the programmer whose values cannot be changed. operators that perform operations on one or more operands. symbolic names made up by the programmer that represents locations in the computer's RAM. reserved words.
symbolic
An object typically hides it data, but allows outside code to access the pseudocode. the methods that operate on the data. private data members. the data files.
the methods that
Application software refers to the programs that make the computer useful to the user. the operating system. key words. pseudocode.
the programs
A procedure is a set of programming language statements that, together, perform a specific task. True False
true
Programming style includes techniques for consistently putting spaces and indentation in a program so visual cues are created. True False
true
The System.out.printf method allows you to format output in a variety of ways. True False
true
The java.lang package is automatically imported into all Java programs. True False
true
Unlike a console program, a program that uses JOptionPane does not automatically stop executing when the end of the main method is reached. True False
true
When you call one of the Scanner class's methods to read a primitive value, such as nextInt or nextDouble, and then call the nextLine method to read a string, an annoying and hard-to-find problem can occur. True False
true
The boolean data type may contain the following range of values: -128 to +127. true or false. -2,147,483,648 to +2,147,483,647. -32,768 to +32,767.
true or false
Application software refers to programs that make the computer useful to the user. True False
ture
Which of the following is not involved in finding the classes when developing an object-oriented application? Describe the problem domain. Write the code. Refine the list of nouns to include only those that are relevant to the problem. Identify all the nouns.
write the code
What will be displayed after the following statements have been executed? int x=15, y=20, z=32; x += 12; y /=6; z -= 14; System.out.println("x= " + x + ", y = " + y + ", z= " + z); x = 27, y = 3.333, z = 18 x = 27, y = 2, z = 18 x = 37, y = -14, z = 4 x = 27, y = 3, z = 18
x=27, y=3, z=18
In UML diagrams, what symbol indicates that a member is public? - * # +
+
The simplest way you can use the System.out.printf method is with a format string, and one format specifier. with only a format string, and no additional arguments. with a format string, and one or more format specifiers. with only one format specifier, and no format string.
2
Which of the following statements correctly creates a Scanner object for keyboard input? Scanner kbd = new Scanner(System.keyboard); Scanner keyboard = new Scanner(System.in); Scanner keyboard(System.in); Keyboard scanner = new Keyboard(System.in);
2
Key words are 1. symbols or words that perform operations on one or more operands. 2. words or names defined by the programmer. 3. the data names in your program. 4. words that have a special meaning in the programming language.
4. words that have a special meaning in the programming language.
What will be the value of z as a result of executing the following code? int x= 5, y=28; float z; z=(float)(y/x); 5.6 3.0 5.0 5.60
5.0
What is the result of the following expression? 17 % 3 *2 -12 +15 105 12 7 8
7
How many bits are in a byte? 4 8 16 32
8