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Inside Macintosh: Programming With MRJToolkit /


Abstract Window Toolkit (AWT) In the Java runtime environment, a collection of functions that allows Java programs to manipulate virtual graphics (windows, images, buttons, and so on). These abstract graphics can be translated into user-visible windows and controls on the client platform. See also AWT Context.

applet In the Java runtime environment, an executable program that must run within a larger host application. In JManager, an instantiated applet is called a JMAppletViewerRef object.

applet tag Text in an HTML document that describes an embedded applet. This text is bounded by the <APPLET> and
</APPLET> delimiters. See also Hypertext Markup Language (HTML).

AWT context An instantiation of an execution environment in the Java runtime environment. An AWT context is a separate thread and may represent a thread group. An AWT context typically contains an applet and one or more frames. In JManager, an AWT context is called a JMAWTContextRef object. See also Abstract Window Toolkit (AWT).

code verifier A bytecode verifier that is part of the Java runtime environment. The code verifier acts as a security measure to make sure the Java code to be executed cannot crash the Java virtual machine or otherwise attempt illegal actions that might allow the code access to the host platform.

creator On the Mac OS platform, a 4-byte character string that identifies the application that created a file.

embedding application The application on a host platform (for example, a Web browser) that instantiates a Java session and executes Java applets or applications.

file system specification record On Mac OS-based platforms, a method of describing the name and location of a file or directory. File system specification records are defined by the FSSpec data type.

Finder The Mac OS application that manages the desktop. The Finder handles opening files and applications as well as maintaining the directory hierarchy.

file type On the Mac OS platform, a 4-byte character string that indicates the contents of a file. For example, files containing raw ASCII text are assigned the file type 'TEXT'.

frame A user interface window in the Java virtual machine. Frames usually contain a title bar and often correspond to a user-visible window. Frames are analogous to a window record on the Mac OS platform. See also parent frame.

HTML See Hypertext Markup Language.

Hypertext Markup Language (HTML) A standard for describing the layout and contents of a hypertext document. An HTML document can contain an applet tag that specifies the name and location of an applet. See also applet tag.

Java runtime environment The Java virtual machine and the associated software required to load and execute Java code. See also virtual machine.

Java runtime session An instantiation of the Java runtime environment (that is, an instantiation of the Java virtual machine and associated software). In JManager a Java runtime session is called a JMSessionRef object. See also virtual machine.

keyboard equivalent A key combination that performs the same action as a menu item.

parent frame The main user interface window associated with an applet. The parent frame is created when the applet is instantiated. In an AWT context, the parent frame has the index value 0. See also frame.

property A data item associated with an object.

session See Java runtime session.

thread An independent event loop in the Java virtual machine. Multiple threads can run concurrently in a Java virtual machine. A thread is also called a lightweight process.

Uniform Resource Locator (URL) A text string that describes the location of an HTML document. A URL may point to a file or to a server that contains the file.

URL See Uniform Resource Locator.

virtual machine (VM) A software package that simulates the actions of a microprocessor. A virtual machine can mimic an existing processor (such as the 68K emulator on PowerPC-based, Mac OS-compatible computers) or parse special VM-specific code. Java code requires a virtual machine environment to execute. See also Java runtime environment, Java runtime session.

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© Apple Computer, Inc.
12 NOV 1997