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A system that runs a very light operating system with no local system administration and executes applications delivered over the network.

A 16-bit character set defined by ISO 10646. See also ASCII. All source code in the Java programming environment is written in Unicode.

A keyword in the Java programming language that, when applied to a method or code block, guarantees that at most one thread at a time executes that code.

The basic unit of program execution. A process can have several threads running concurrently, each performing a different job, such as waiting for events or performing a time-consuming job that the program doesn't need to complete before going on. When a thread has finished its job, the thread is suspended or destroyed. See also process.

A Java keyword used in method declarations that specify which exceptions are not handled within the method but rather passed to the next higher level of the program.

The degree to which the intermediate state of the data being modified by a transaction is visible to other concurrent transactions and data being modified by other transactions is visible to it.

A Java keyword that defines a block of statements that may throw a Java language exception. If an exception is thrown, an optional catch block can handle specific exceptions thrown within the try block. Also, an optional finally block will be executed regardless of whether an exception is thrown or not.

Uniform Resource Name. A unique identifier that identifies an entity, but doesn't tell where it is located. A system can use a URN to look up an entity locally before trying to find it on the Web. It also allows the Web location to change, while still allowing the entity to be found.

A Java keyword used in method declarations to specify that the method does not return any value. void can also be used as a nonfunctional statement.

A Java keyword used to declare a loop that iterates a block of statements. The loop's exit condition is specified as part of the while statement.

An object that encapsulates and delegates to another object to alter its interface or behavior in some way.

A keyword in the Java programming language that indicates that a field is not part of the serialized form of an object. When an object is serialized, the values of its transient fields are not included in the serial representation, while the values of its non-transient fields are included.

A class or interface.

Transmission Control Protocol based on IP. This is an Internet protocol that provides for the reliable delivery of streams of data from one host to another. See also IP.

A test suite, a set of tools, and other requirements used to certify an implementation of a particular Sun technology conformant both to the applicable specifications and to Sun or Sun-designated reference implementations.

A Java keyword that can be used to represent an instance of the class in which it appears. this can be used to access class variables and methods.

A Java keyword that allows the user to throw an exception or any class that implements the "throwable" interface.

Provides the services and management functions required to support transaction demarcation, transactional resource management, synchronization, and transaction context propagation.

A collection of graphical user interface (GUI) components that runs uniformly on any native platform which supports the Java virtual machine*. Because they are written entirely in the Java programming language, these components may provide functionality above and beyond that provided by native-platform equivalents. (Contrast with AWT.)

A Java keyword used in variable declarations that specifies that the variable is modified asynchronously by concurrently running threads.

An abstract specification for a computing device that can be implemented in different ways, in software or hardware. You compile to the instruction set of a virtual machine much like you'd compile to the instruction set of a microprocessor. The Java virtual machine consists of a bytecode instruction set, a set of registers, a stack, a garbage-collected heap, and an area for storing methods.

An item of data named by an identifier. Each variable has a type, such as int or Object, and a scope. See also class variable, instance variable, local variable.

Uniform Resource Locator. A standard for writing a text reference to an arbitrary piece of data in the WWW. A URL looks like "protocol://host/localinfo" where protocol specifies a protocol to use to fetch the object (like HTTP or FTP), host specifies the Internet name of the host on which to find it, and localinfo is a string (often a file name) passed to the protocol handler on the remote host.

Files on a file system that can be viewed (read) by any user. For example: files residing on Web servers can only be viewed by Internet users if their permissions have been set to world readable.

A scope over which security policies are defined and enforced by a security administrator. A security policy domain has the following characteristics:
It has a collection of users (or principals).
It uses a well defined authentication protocol(s) for authenticating users (or principals).
It may have groups to simplify setting of security policies.