Glossary J

Java

A programming language similar to C++. Java is currently popular because it is compiled to machine-independent bytecode. This allows programmers to write one kind of program code for all platforms (Macintosh, Windows 3.x, Windows NT, Windows 95, UNIX). Software components written in Java for the Web are called applets. Java applets access code libraries on local clients and can download additional class files from the server.

JIT compiler

Just-In-Time compiler for Java. The JIT compiler takes the Java bytecode (which is machine-independent) and compiles it on demand into native code for the target machine, giving faster execution. Since JIT compilers operate on the client machine, they preserve the platform-independence of the compiled Java program.

JIT debugging

A technique that catches faults that occur while the program is running outside the debugging environment and can start the debugging. You must set this option in the development environment before executing your program.

join

A database operation that combines records from two or more tables, based on an exact match of key values in these tables. Once a recordset has been created based on a join, it functions as if the records were all in one table.

Joint Photographic Experts Group

An algorithm for graphics file storage, supported by many Web browsers. JPEG was developed for compressing and storing photographic images and is best used for graphics containing many colors, such as scanned photos. Most files that are compressed using JPEG are stored in a file format called JFIF (JPEG File Interchange Format). See also Graphics Interchange Format (GIF).

JPEG

An algorithm for graphics file storage, supported by many Web browsers. JPEG was developed for compressing and storing photographic images and is best used for graphics containing many colors, such as scanned photos. Most files that are compressed using JPEG are stored in a file format called JFIF (JPEG File Interchange Format). See also Graphics Interchange Format (GIF).

jump

A word, phrase, or button in a Help topic that, when clicked, takes the user to another topic screen in the Help system.

jump statement

A statement that either transfers control immediately to another location in the function or returns control from the function. In C++, the jump statements are break, continue, return, and goto.

Just-in-Time debugging

A technique that catches faults that occur while the program is running outside the development environment. You must set this option in the development environment before executing your program.