chapter 1 creating java programs
hardware
the general term for computer equipment.
software
the general term for computer programs.
computer program
a set of instructions that tells a computer what to do; software. See also program.
program
a set of instructions that tells a computer what to do; software. See also computer program.
program
a set of instructions that tells a computer what to do; software. See also computer program.
application software
programs that perform tasks for users. Contrast with system software.
system software
the set of programs that manage the computer. Contrast with application software.
logic
describes the order of program statements that produce correct results.
high-level programming language
a language that uses a vocabulary of reasonable terms, such as read, write, or add, instead of referencing the sequences of on and off switches that perform these tasks. Contrast with low-level programming language.
low-level programming language
a language that corresponds closely to a computer processor’s circuitry. Contrast with high-level programming language. Compare with machine language.
Machine language
circuitry-level language; a series of on and off switches. Compare with low-level programming language.
machine code
machine language.
syntax
the rules that define how language elements are used together correctly to create usable statements.
keywords
the words that are part of a programming language.
program statements
similar to English sentences; instructions that carry out the tasks that programs perform.
commands
program statements.
compiler
a program that translates language statements into machine code, translating an entire program before executing it. Contrast with interpreter.
interpreter
a program that translates language statements into machine code. An interpreter translates and executes one statement at a time. Contrast with compiler.
executing
the act of carrying out a program statement or program.
at run time
describes the period of time during which a program executes.
syntax error
a programming error that occurs when a program contains typing errors or incorrect language use; a program containing syntax errors cannot be translated into an executable program.
debugging
the process of locating and repairing a program’s errors.
bugs
flaws or mistakes in a computer program.
logic error
a programming bug that allows a source program to be translated to an executable program successfully, but that produces incorrect results.
semantic errors
the type of errors that occur when a correct word is used in the wrong context in program code.
Procedural programming
style of programming in which sets of operations are executed one after another in sequence. Contrast with object-oriented programs.
variable
a named memory location whose contents can be altered during program execution.
procedures
sets of operations performed by a computer program.
call a procedure
to invoke a method.
object-oriented programs
programs that use a style of programming that involves creating classes, creating objects from those classes, and creating applications that use those objects. Contrast with procedural programming.
Computer simulations
programs that attempt to mimic real-world activities so that their processes can be improved or so that users can better understand how the real-world processes operate.
Graphical user interfaces (GUIs)
environments that allow users to interact with a program in a graphical environment.
class
a group or collection of objects with common properties.
class definition
a description of attributes and methods of objects instantiated from a class.
Attributes
the characteristics that define an object as part of a class.
properties
the characteristics that define an object; an instance variable, field, or attribute of a class.
object
an instance of a class.
instance
an existing object of a class.
instantiation
refers to the process of creating an object, and also describes one tangible object created from a class.
state
the values of the attributes of an object.
method
a program module that contains a series of statements that carry out a task.
Encapsulation
the act of hiding data and methods within an object.
inheritance
a mechanism that enables one class to inherit, or assume, both the behavior and the attributes of another class.
polymorphism
the feature of languages that allows the same word to be interpreted correctly in different situations based on the context; the act of using the same method name to indicate different implementations.
Java
an object-oriented programming language used both for general-purpose business applications and for interactive, Web-based Internet applications.
architecturally neutral
escribes the feature of Java that allows a program to run on any platform.
Java Virtual Machine (JVM)
a hypothetical (software-based) computer on which Java runs.
source code
programming statements written in a high-level programming language.
development environment
a set of tools that helps programmers by providing such features as displaying a language’s keywords in color.
bytecode
programming statements that have been compiled into binary format.
Java interpreter
the program that checks bytecode and communicates with the operating system, executing the bytecode instructions line by line within the Java Virtual Machine.
“Write once, run anywhere” (WORA)
a slogan developed by Sun Microsystems to describe the ability of one Java program version to work correctly on multiple platforms.
Console applications
programs that support character or text output to a computer screen.
Windowed applications
programs that create a graphical user interface (GUI) with elements such as menus, toolbars, and dialog boxes.
literal string
a series of characters that appear exactly as entered; in Java, a literal string appears between double quotation marks.
Arguments
data items sent to methods in a method call.
passing arguments
the act of sending arguments to a method.
standard output device
usually the monitor.
identifier
the name of a program component such as a class, object, or variable.
Unicode
an international system of character representation.
Pascal casing
the style of using an uppercase letter to begin an identifier and to start each new word in an identifier. Contrast with camel casing. Compare to upper camel casing.
upper camel casing
the style of using an uppercase letter to begin an identifier and to start each new word in an identifier. Also called Pascal casing.
class header
the first line of a class that contains an access specifier, the keyword class, and the class identifier.
public
a Java keyword that describes how methods can access a field or method.
access specifier
defines the circumstances under which a class can be accessed; often used interchangeably with access modifier.
class body
the set of data items and methods between the curly braces that follow the class header.
method header
the declaration or first line of a method that contains information about how other methods interact with it.
static
a keyword that means a method is accessible and usable even though no objects of the class exist.
void
a keyword that, when used in a method header, indicates that the method does not return any value when it is called.
String class
a Java class that can be used to hold character strings.
Whitespace
any combination of nonprinting characters; for example, spaces, tabs, and carriage returns (blank lines).
K & R style
the indent style in which the opening brace follows the header line; it is named for Kernighan and Ritchie, who wrote the first book on the C programming language. Contrast with Allman style.
Allman style
the indent style in which curly braces are aligned and each occupies its own line; named for Eric Allman, a programmer who popularized the style. Contrast with K & R style.
compile-time error
an error for which the compiler detects a violation of language syntax rules and is unable to translate the source code to machine code.
Parsing
the process of breaking something into its component parts.
clean build
a compilation that is created after deleting all previously compiled versions of a class.
runtime error
an error that occurs when a program compiles successfully but does not execute.
Program comments
nonexecuting statements added to a Java file for documentation.
comment out
the technique of turning a program statement into a comment so the compiler will not execute its command.
Line comments
comments that start with two forward slashes ( // ) and continue to the end of the current line. Line comments can appear on a line by themselves or at the end of a line following executable code. Contrast with block comments.
Block comments
omments that start with a forward slash and an asterisk ( /* ) and end with an asterisk and a forward slash ( */ ). Block comments can appear on a line by themselves, on a line before executable code, or on a line after executable code. Block comments also can extend across as many lines as needed. Contrast with line comments.
Javadoc
a documentation generator that creates Application Programming Interface (API) documentation in Hypertext Markup Language (HTML) format from Java source code.
documentation comments
comments that automatically generate well-formatted program documentation.
dialog box
a GUI object resembling a window that displays messages. See also input dialog box and confirm dialog box.
import statement
a Java statement that allows access to a built-in Java class that is contained in a package.
package
a named collection or library of classes. See also library of classes.
Java API
the application programming interface, a collection of information about how to use every prewritten Java class.
FAQs
acronym for Frequently Asked Questions.
JDK
the Java Standard Edition Development Kit.
SDK
Definition:
a software development kit, or a set of tools useful to programmers; the Java EE Development Kit.
Write once, run anywhere (WORA)
a slogan developed by Sun Microsystems to describe the ability of one Java program version to work correctly on multiple platforms.