Abstract Window Toolkit

The class library that provides the standard API for building GUIs for Java programs. The Abstract Window Toolkit (AWT) includes imaging tools, data transfer classes, GUI components, containers for GUI components, an event system for handling user and system events among parts of the AWT, and layout managers for managing the size and position of GUI components in platform-independent designs. (The GUI components in the AWT are implemented as native-platform versions of the components, and they have largely been supplanted by the Swing components.) See also Java Foundation Classes, Swing classes.

accessibility

The degree to which software can be used comfortably by a wide variety of people, including those who require assistive technologies like screen magnifiers or voice recognition. An accessible JFC application employs the Java Accessibility API, enables its users to select an appropriate look and feel, and provides keyboard operations for all actions that can be carried out by use of the mouse. See also Java Accessibility API, Java Accessibility Utilities, keyboard operations.

alert box

A dialog box used by an application to convey a message or warning or to gather information from the user. Four standard alert boxes (Question, Info, Error, and Warning) are supplied for JFC applications. Alert boxes are created using the JOptionPane component. See also dialog box.

applet

A program, written in the Java language, that a user can interact with in a web browser. See also application.

application

A program that combines all the functions necessary for a user to accomplish a particular set of tasks (for instance, word processing or inventory tracking). Unless stated otherwise, this book uses "application" to refer to both applets and standalone applications. See also applet.

assistive technology

Hardware or software that helps people with disabilities use a computer (or provides alternative means of use to all users). Examples include pointing devices other than the mouse, audio or text-only browsers, and screen readers that translate the contents of the screen into Braille, voice output, or audible cues.

AWT

See Abstract Window Toolkit.

bit depth

The amount of information (in bits) used to represent a pixel. A bit depth of 8 supports up to 256 colors; a bit depth of 24 supports up to 16,777,216 colors.

browser

An application that enables users to view, navigate through, and interact with HTML documents and applets. Also called a "web browser."

button

A collective term for the various controls whose on-screen appearance typically simulates a push button or a radio button. The user clicks buttons to specify commands or set options. See also checkbox, command button, radio button, toggle button, toolbar button.

checkbox

A control, consisting of a graphic and associated text, that a user clicks to select or deselect an option. A check mark in the checkbox graphic indicates that the option is selected. Checkboxes are created using the JCheckBox component. See also radio button.

checkbox menu item

A menu item that appears with a checkbox next to it to represent an on or off setting. A check mark in the checkbox graphic indicates that the menu item is selected. Checkbox menu items are created using the JCheckBoxMenuItem component. See also menu item.

color chooser

A component that enables a user to select a color. Color choosers are created using the JColorChooser component. See also HSB, palette window, RGB, utility window.

combo box

A component with a drop-down arrow that the user clicks to display a list of options. Noneditable combo boxes (sometimes called "list boxes") have a list from which the user can select one item. Editable combo boxes offer a text field as well as a list of options. The user can make a selection by typing a value in the text field or by selecting an item from the list. Combo boxes are created using the JComboBox component.

command button

A button with a rectangular border that contains text, a graphic, or both. A user clicks a command button to specify a command to initiate an action. Command buttons are created using the JButton component. See also button, toggle button, toolbar button.

component

A piece of code or, by extension, the interface element implemented by that code. See also Swing classes.

container

A component (such as an applet, window, pane, or internal frame) that holds other components.

contextual menu

A menu that is displayed when a user presses mouse button 2 while the pointer is over an object or area associated with that menu. A contextual menu offers only menu items that are applicable to the object or region at the location of the pointer. Sometimes called a "pop-up menu." Contextual menus are created using the JPopupMenu component. See also menu.

control

An interface element that a user can manipulate to perform an action, select an option, or set a value. Examples include buttons, sliders, and combo boxes.

cross-platform

Pertaining to heterogeneous computing environments. For example, a cross-platform application is one that has a single code base for multiple operating systems.

cursor

See pointer.

default command button

The command button that the application activates if a user presses Enter or Return. Default buttons in Java look and feel applications have a heavier border than other command buttons. See also command button.

designer

A professional who specifies the way that users will interact with an application, chooses the interface components, and lays them out in a set of views. The designer might or might not be the same person as the developer who writes the application code.

desktop pane

A container, a sort of "virtual desktop," for an MDI application. Desktop panes are created using the JDesktopPane component. See also internal frame, MDI.

dialog box

A secondary window displayed by an application to gather information from users or to inform them of a condition. A dialog box can contain panes, lists, buttons, and other components. Dialog boxes are created using the JDialog component. See also alert box, color chooser, palette window, secondary window, utility window.

dithering

Simulating unavailable colors in a displayed graphic by using a pattern of two or more available colors.

drag

To move the mouse while holding down a mouse button. See also drag and drop.

drag and drop

To drag an interface element to a new location in order to move, copy, or link it. See also drag.

drop-down arrow

The triangular indicator that a user clicks to view more options than are visible on screen--such as the list attached to a combo box or the options provided by some toolbar buttons.

drop-down menu

A menu that is displayed when a user chooses a menu title in the menu bar. Drop-down menus are created using the JMenu component. See also menu, menu bar.

editor pane

A component that supports a variety of plug-in editor kits. The JFC includes editor kits that can display plain, styled, HTML, and RTF data. Editor panes are created using the JEditorPane component. See also plug-in editor kit.

flush 3D style

In the Java look and feel, the effect created by rendering on-screen graphics whose surfaces appear to be in the same plane as the surrounding canvas.

GIF

Graphics Interchange Format. An 8-bit graphics format developed by CompuServe and commonly used on the World Wide Web. GIF files are limited to 256 colors, and they compress without loss of information. The GIF format is typically used for graphics in the Java look and feel. See also bit depth, JPEG.

HSB

For "hue, saturation, brightness." In computer graphics, a color model in which hue refers to a color's light frequency, saturation is the amount or strength of the hue (its purity), and brightness is the amount of black in the color (its lightness or darkness). See also RGB.

icon

An on-screen graphic representing an interface element that a user can select or manipulate--for example, an application, document, or disk.

insertion point

The place, usually indicated by a blinking bar, where typed text or a dragged or pasted selection will appear. See also pointer.

internal frame

A container used in MDI applications to create windows that a user cannot drag outside of the desktop pane. In an MDI application that uses the Java look and feel, internal frames have a window border, title bar, and standard window controls with the Java look and feel. Internal frames are created using the JInternalFrame component. See also desktop pane, MDI.

internationalization

The process of preparing software that is suitable for the global marketplace, taking into account wide variations in regions, languages, and cultures. Internationalization usually requires the separation of component text from code to ease the process of translation. See also localization.

Java 2D API

A programming interface (part of the Java Foundation Classes in the Java 2 SDK) that provides an advanced two-dimensional imaging model for complex shapes, text, and images. Features include enhanced font and color support and a single, comprehensive rendering model. See also Java Foundation Classes.

Java 2 SDK

The software development kit that developers need to build applications for the Java 2 Platform, Standard Edition, v. 1.2. See also Java Development Kit.

Java Accessibility API

A programming interface (part of the Java Foundation Classes) that enables assistive technologies to interact and communicate with JFC components. A Java application that fully supports the Java Accessibility API is compatible with such technologies as screen readers and screen magnifiers. See also accessibility, assistive technology, Java Accessibility Utilities, Java Foundation Classes.

Java Accessibility Utilities

A set of classes (provided in the Java 2 SDK) for use by the vendors who create assistive technologies or automated tool tests. See also accessibility, assistive technology, Java Accessibility API, Java Foundation Classes.

Java Development Kit

Software that includes the APIs and tools that developers need to build applications for those versions of the Java platform that preceded the Java 2 Platform. Also called the "JDK." See also Java 2 SDK.

Java Foundation Classes

A product that includes the Swing classes, pluggable look and feel designs, and the Java Accessibility API (all implemented without native code and compatible with JDK 1.1). For the Java 2 platform, the Java Foundation Classes (JFC) also include the Java 2D API, drag and drop, and other enhancements. See also Abstract Window Toolkit, pluggable look and feel architecture, Swing classes.

Java look and feel

The default appearance and behavior for JFC applications, designed for cross-platform use. The Java look and feel works in the same way on any platform that supports the Java Foundation Classes. See also Java Foundation Classes, pluggable look and feel architecture.

JDK

See Java Development Kit.

JFC

See Java Foundation Classes.

JFC application

An application built with the Java Foundation Classes. See also Java Foundation Classes.

JPEG

A graphics format developed by the Joint Photographic Experts Group. The JPEG format is frequently used for photographs and other complex images that benefit from a larger color palette than a GIF image can provide. JPEG compression is "lossy"; decompressed images are not identical to uncompressed images. See also GIF.

keyboard focus

The active window or component where the user's next keystrokes will take effect. Sometimes called the "input focus."

keyboard operations

A collective term for keyboard shortcuts, mnemonics, and other forms of navigation and activation that utilize the keyboard instead of the mouse. See also keyboard shortcut, mnemonic.

keyboard shortcut

A keystroke combination (usually a modifier key and a character key, like Control-C) that activates a menu item from the keyboard even if the relevant menu is not currently displayed. See also keyboard operations, mnemonic.

label

Static text that appears in the interface. For example, a label might identify a group of checkboxes. (The text that accompanies each checkbox within the group, however, is specified in the individual checkbox component and is therefore not considered a label.) Labels are created using the JLabel component.

layout manager

An object that assists the designer in determining the size and position of components within a container. Each container type has a default layout manager. See also Abstract Window Toolkit.

list

A set of choices from which a user can select one or more items. Items in a list can be text, graphics, or both. Lists are created using the JList component. See also combo box.

localization

The process of customizing software for a particular locale. Localization usually involves translation and often requires changes to fonts, keyboard usage, and date and time formats. See also internationalization.

look and feel

The appearance and behavior of a complete set of GUI components. See also Java look and feel.

MDI

Multiple document interface. An interface that confines all of an application's internal frames inside its desktop pane. See also desktop pane.

menu

A list of choices (menu items) logically grouped and displayed by an application so that a user need not memorize all available commands or options. Menus in the Java look and feel are "sticky"--that is, they remain posted on screen after the user clicks the menu title. Menus are created using the JMenu component. See also contextual menu, drop-down menu, menu bar, menu item, submenu.

menu bar

The horizontal strip at the top of a window that contains the titles of the application's drop-down menus. Menu bars are created using the JMenuBar component. See also drop-down menu.

menu item

A choice in a menu. Menu items (text or graphics) are typically commands or other options that a user can select. Menu items are created using the JMenuItem component. See also checkbox menu item, radio button menu item.

middle mouse button

The central button on a three-button mouse (typically used in UNIX environments). The Java look and feel does not utilize the middle mouse button. See also mouse button 2.

MIME

Multipurpose Internet Mail Extensions. An Internet standard for sending and receiving non-ASCII email attachments (including video, audio, and graphics). Web browsers also use MIME types to assign applications to interpret and display files that are not written in HTML.

minimized internal frame

A reduced representation of an internal frame in an MDI application. Minimized internal frames look like horizontally oriented tags that appear at the lower-left corner of the desktop. The user can drag minimized internal frames to rearrange them. See also MDI.

mnemonic

An underlined letter, typically in a menu title, menu item, or the text of a button or component. A mnemonic shows the user which key to press (in conjunction with the Alt key) to activate a command or navigate to a component. See also keyboard operations, keyboard shortcut.

modal dialog box

In a JFC application, a dialog box that prevents the user's interaction with other windows in the current application. Modal dialog boxes are created using the JDialog component. See also dialog box, modeless dialog box.

modeless dialog box

In a JFC application, a dialog box whose presence does not prevent the user from interacting with other windows in the current application. Modeless dialog boxes are created using the JDialog component. See also dialog box, modal dialog box.

modifier key

A key (for example, the Control or the Shift key) that does not produce an alphanumeric character but rather modifies the action of other keys.

mouse button 1

The primary button on a mouse (the only button, for Macintosh users). By default, mouse button 1 is the leftmost button, though users might switch the button settings so that the rightmost button becomes mouse button 1. See also middle mouse button, mouse button 2.

mouse button 2

On a two-button or three-button mouse, the button that is used to display contextual menus. By default, mouse button 2 is the rightmost button on the mouse, though users might switch the settings so that the leftmost button becomes mouse button 2. See also contextual menu, middle mouse button, mouse button 1.

mouse-over feedback

A change in the visual appearance of an interface element that occurs when the user moves the pointer over it--for example, the display of a button border when the pointer moves over a toolbar button.

multiple document interface

See MDI.

native code

Code that refers to the methods of a specific operating system or is compiled for a specific processor.

palette window

In an MDI application with the Java look and feel, a modeless window that displays a collection of tools, colors, or patterns. Palette windows float on top of document windows. User choices made in a palette window affect whichever primary window is active. Palette windows are created using the JInternalFrame component. See also utility window.

pane

A collective term for scroll panes, split panes, and tabbed panes.

panel

A container for organizing the contents of a window, dialog box, or applet. Panels are created using the JPanel component. See also tabbed pane.

password field

A special text field in which the user types a password. The field displays a masking character for each typed character. Password fields are created using the JPasswordField component.

plain window

An unadorned window with no title bar or window controls, typically used for splash screens. Plain windows are created using the JWindow component. See also primary window, window controls.

pluggable look and feel architecture

An architecture that separates the implementation of interface elements from their presentation, enabling an application to dynamically choose how its interface elements interact with users. When a pluggable look and feel is used for an application, the designer can select from several look and feel designs.

plug-in editor kit

An editor that can be used by the editor pane. The Java Foundation Classes supply plug-in editor kits for plain, styled, RTF, and HTML data.

pointer

A small graphic that moves around the screen as the user manipulates the mouse (or another pointing device). Depending on its location and the active application, the pointer can assume various shapes, such as an arrowhead, crosshair, or clock. By moving the pointer and pressing mouse buttons, a user can select objects, set the insertion point, and activate windows. Sometimes called the "cursor." See also insertion point.

preference

A setting for an application or tool. Typically set by users. See also property.

primary window

A top-level window of an application, where the principal interaction with the user occurs. Primary windows always retain the look and feel of the user's native platform. Primary windows are created using the JFrame component. See also dialog box, secondary window.

progress bar

An interface element that indicates one or more operations are in progress and shows the user what proportion of the operations has been completed. Progress bars are created using the JProgressBar component. See also control, slider.

property

A characteristic of an object. Depending on the object, the user or the designer might set its properties. See also preference.

radio button

A button that a user clicks to set an option. Unlike checkboxes, radio buttons are mutually exclusive--selecting one radio button deselects all other radio buttons in the group. Radio buttons are created using the JRadioButton component. See also checkbox.

radio button menu item

A menu item that appears with a radio button next to it. Separators indicate which radio button menu items are in a group. Selecting one radio button menu item deselects all others in that group. Radio button menu items are created using the JRadioButtonMenuItem component.

resource bundle

The place where an application stores its locale-specific data (isolated from source code).

RGB

For "red, green, blue." In computer graphics, a color model that represents colors as percentages of red, green, and blue. See also HSB.

scroll arrow

In a scrollbar, one of the arrows that a user can click to move through displayed information in the corresponding direction (up or down in a vertical scrollbar, left or right in a horizontal scrollbar). See also scrollbar.

scroll box

A box that a user can drag in the channel of a scrollbar to cause scrolling in the corresponding direction. The scroll box's position in the scrollbar indicates the user's location in the list, window, or pane. In the Java look and feel, the scroll box's size indicates what proportion of the total information is currently visible on screen. A large scroll box, for example, indicates that the user can peruse the contents with just a few clicks in the scrollbar. See also scrollbar.

scroll pane

A container that provides scrolling with optional vertical and horizontal scrollbars. Scroll panes are created using the JScrollPane component. See also scrollbar.

scrollbar

A component that enables a user to control what portion of a document or list (or similar information) is visible on screen. A scrollbar consists of a vertical or horizontal channel, a scroll box that moves through the channel of the scrollbar, and two scroll arrows. Scrollbars are created using the JScrollBar component. See also scroll arrow, scroll box, scroll pane.

secondary window

A modal or modeless window created from and dependent upon a primary window. Secondary windows set options or supply additional details about actions and objects in the primary window. Secondary windows are dismissed when their associated primary window is dismissed. Secondary windows are created using either the JFrame or the JDialog component. See also dialog box, primary window.

separator

A line graphic that is used to divide menu items into logical groupings. Separators are created using the JSeparator component.

slider

A control that enables the user to set a value in a range--for example, the RGB values for a color. Sliders are created using the JSlider component. See also progress bar.

split pane

A container that enables the user to adjust the relative size of two adjacent panes. Split panes are created using the JSplitPane component.

submenu

A menu that is displayed when a user chooses a certain menu item in a higher-level menu. Submenus are created using the JMenu component.

Swing classes

A set of GUI components, featuring a pluggable look and feel, that are included in the Java Foundation Classes. The Swing classes implement the Java Accessibility API and supply code for interface elements such as windows, dialog boxes and choosers, panels and panes, menus, controls, text components, tables, lists, and tree views. See also Abstract Window Toolkit, Java Foundation Classes, pluggable look and feel architecture.

tabbed pane

A container that enables the user to switch between several components (usually JPanel components) that appear to share the same space on screen. The user can view a particular panel by clicking its tab. Tabbed panes are created using the JTabbedPane component.

table

A two-dimensional arrangement of data in rows and columns. Tables are created using the JTable component.

text area

A multiline region for displaying (and sometimes editing) text. Text in such areas is restricted to a single font, size, and style. Text areas are created using the JTextArea component. See also editor pane.

text field

An area that displays a single line of text. In a noneditable text field, a user can copy, but not change, the text. In an editable text field, a user can type new text or edit the existing text. Text fields are created using the JTextField component. See also password field.

theme mechanism

A feature that enables a designer to specify alternative colors and fonts across an entire Java look and feel application. See also Java look and feel.

title bar

The strip at the top of a window that contains its title and window controls. See also window controls.

toggle button

A button that alternates between two states. For example, a user might click one toggle button in a toolbar to turn italics on and off. A single toggle button has checkbox behavior; a programmatically grouped set of toggle buttons can be given the mutually exclusive behavior of radio buttons. Toggle buttons are created using the JToggleButton component. See also toolbar button.

tool tip

A short text string that appears on screen to describe the interface element beneath the pointer.

toolbar

A collection of frequently used commands or options. Toolbars typically contain buttons, but other components (such as text fields and combo boxes) can be placed in toolbars as well. Toolbars are created using the JToolBar component. See also toolbar button.

toolbar button

A button that appears in a toolbar, typically a command or toggle button. Toolbar buttons are created using the JButton or JToggleButton component. See also command button, toggle button.

top-level container

The highest-level container for a Java application or applet. The top-level containers are JWindow, JFrame, and JDialog.

tree view

A representation of hierarchical data (for example, directory and file names) as a graphical outline. Clicking expands or collapses elements of the outline. Tree views are created using the JTree component.

turner

A graphic used in the tree view component. The user clicks a turner to expand or collapse a container in the hierarchy.

utility window

In a non-MDI application with the Java look and feel, a modeless dialog box that typically displays a collection of tools, colors, fonts, or patterns. Unlike palette windows, utility windows do not float. User choices made in a utility window affect whichever primary window is active. A utility window is not dismissed when a primary window is dismissed. Utility windows are created using the JDialog component. See also palette window, secondary window.

web browser

See browser.

window

See dialog box, palette window, plain window, primary window, secondary window, utility window.

window controls

Controls that affect the state of a window (for example, the Maximize button in Microsoft Windows title bars).