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Abstract A modifier of a class field that indicates it is incomplete and must be
fully defined in a derived class
Abstract step A step for which some implementation details remain unspecified
Abstraction The separation of the logical properties of an object from its imple-
mentation
Access modifiers Reserved words in Java that specify where a class, method, or
field may be accessed
Algorithm Instructions for solving a problem in a finite amount of time using a
finite amount of data
Anonymous object An object that is instantiated but not assigned to an identi-
fier and, therefore, lacks a name
Argument An expression used for communicating values to a method
Arithmetic/logic unit (ALU) The component of the central processing unit that
performs arithmetic and logical operations
Array A collection of components, all of the same type, ordered onN dimensions
(N>=1). Each component is accessed by Nindexes, each of which represents
the component’s position within that dimension
Assembler A program that translates an assembly language program into
machine code
Assembly language A low-level programming language in which a mnemonic
represents each machine language instruction for a particular computer
Assignment expression A Java expression with (1) a value and (2) the side effect
of storing the expression value into a memory location
Assignment statement A statement that stores the value of an expression into
a variable
Asynchronous Not occurring at the same moment in time as some specific op-
eration of the computer; not synchronized with the computer’s actions
Atomic (simple) elements Elements that have no component parts
Auxiliary storage device A device that stores data in encoded form outside the
computer’s main memory
Base address The memory address of the first element of an array
Base case The case for which the solution can be stated non-recursively
Binary operator An operator that has two operands
Button A component that can be added to a frame and that fires an event (called
a button event) when the user clicks it with the mouse
Bytecode A standard machine language into which Java source code is compiled
Call A statement that causes a method to be executed; in Java we call a method
by writing its name, followed by a list of arguments enclosed in parentheses
Caught exception An exception in Java that must either be caught with a catch
statement or explicitly thrown to the next level
Central processing unit (CPU) The part of the computer that executes the
instructions (object code) stored in memory; made up of the arithmetic/logic
unit and the control unit
Character stream file A file that is stored as a sequence of characters
Class A description of the representation of a specific kind of object, in terms of
data and operational behaviors
Class A definition for an object or an application in Java
Class field A field that belongs to a class rather than its object instances; identi-
fied as such with the modifier