Concepts of the JADE Language

The JADE language is the programming language in which JADE methods are written.

You can write external methods using other programming languages (for example, Pascal or C++), but JADE is the language of choice, for the following reasons.

• It has a simple, regular syntax

• It provides seamless access to the JADE Object Manager and user-interface components

• It includes specialized constructs for exploiting some of the more-powerful features of the JADE environment

In JADE, procedural-style control structures and arithmetic expressions are combined with object-oriented message-passing syntax. Message-passing uses a "." (dot) notation.

JADE is a strongly typed language, in which you must explicitly state the type of each identifier. When instructions refer to methods or properties, the compiler checks that the method or property has been defined for the corresponding objects. This strong typing provides the following benefits.

• Reduced risk of runtime errors due to invalid methods being invoked

• Early error detection

The JADE language syntax makes no distinction between transient and persistent objects. The same syntax is used for creating, maintaining, and deleting transient and persistent objects.

Methods can be invoked for transient objects in the same way as they can for persistent objects.