Wiki code for Features

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1: 1 Features
2: 
3: The following sections highlight some of the current features of Jadex.
4: In summary, Jadex is an *agent-* and *Java-based*, *modular*, 
5: *conceptually leading*, *technology affine* and *standards compliant*, 
6: agent environment, and allows to develop *goal oriented agents* following the BDI model.
7: Jadex provides a *framework* approach including a runtime infrastructure for agents, the
8: agent platform, and an extensive runtime tool suite.
9: 
10: 1.1 Agent-based
11: 
12: The agent concept is regarded as a powerful software development paradigm,
13: well suited to address the complexity of todays large software systems. It
14: can be considered as a natural extension to object-orientation, whereby an
15: agent represents an object with control about its execution. The agent paradigm 
16: allows to view a system as being composed of autonomous interacting entities 
17: which pursue their own goals and act in a rational manner. Interestingsly, 
18: the agent metaphor fits perfectly to the demands of *distributed and concurrent systems*. 
19: In a multi-agent system each agent is autonomous from other agents
20: and hence potentially concurrently executed to the others. In addition, 
21: agents communication via messages and do not need a shared memory environment
22: (like objects using method calls).
23: 
24: 1.1 Java-based
25: 
26: The Jadex project aims to make the development of agent based systems
27: as easy as possible without sacrificing the expressive power of the agent
28: paradigm. To foster a smooth transition from traditional distributed systems 
29: to the development of multi-agent systems, well established *object-oriented concepts* 
30: and technologies should be employed wherever possible.
31: With Jadex you are able to create agent systems without having to learn a new
32: programming language. Jadex is designed to facilitate the implementation of
33: agents in the widespread Java programming language, therefore allowing to
34: reuse a vast amout of existing tools and libraries.
35: 
36: 1.1 Modular Design
37: 
38: Jadex has been developed in a very modular fashion. This modular design has on major goal:
39: the clean separation between the agent platform and the agent kernel. This separation allows
40: a many-to-many relationship between agent platforms (i.e. Standalone or JADE) and kernels 
41: (i.e. BDI or Micro). I.e., on the one hand, on a specifc agent platform different kernels
42: can be run (also concurrently) and hybrid agent applications can be built. On the other
43: hand, a specifc agent kernel can also be run on different agent platforms (requirement is that
44: a Jadex adapter has been built). This allows the execuation of e.g. BDI agent programs
45: on the Standalone or JADE platform without requiring any changes to the agent code. 
46: 
47: 1.1 Conceptually Leading 
48: 
49: The Jadex framework is developed since 2003. From the beginning, the project has the aim
50: to reveal and provide the best possible support for building distributed and concurrent programs.
51: This class of software gains ever increasing importance by many factors and current trends such
52: as ubiquitous computing and multicore processors. Hence, Jadex has alsways been driven by
53: new research ideas and incorporates these as new features as soon as possible in the software. 
54: Some examples of these outstanding features are:
55: 
56: * Incorporated event- and time-driven simulation support
57: * Multi agent kernel support
58: * Full BDI-reasoning cycle support (goal deliberation and means-end reasoning)
59: * Goal-oriented interaction protocols
60: * Many prebuilt functionalities readily available in capabilities
61: 
62: 1.1 Technology Affine
63: 
64: Even though Jadex is driven by research ideas, the technology side is considered equally important
65: and non-functional aspects like robustness, scalability, fault tolerance etc. have been targeted
66: specifically in the new Jadex V2 design. It is always tried to exploit the best of breed software
67: for Jadex and make use of proven technology. This is reflected e.g. by:
68: 
69: * Maven is used as build and release tool
70: * The Standalone platform realizes a services based approach and can be configured e.g. with Spring Beans
71: * BDI kernel is built on established and efficient rule technology (RETE engine)
72: 
73: <table border="0" cellspacing="0" cellpadding="0">
74: <tbody>
75: <tr>
76: <td valign="top">
77: <h2>Standards Compliant</h2>
78: <p>
79: Standards are important to ensure that agreed best practices are used and
80: standards compliance allows consumers of technologies to exchange products
81: of different vendors lowering the risks of a vendor lock-in. In the field
82: of multi-agent systems only a few standards have been developed so far. Jadex
83: aims at following standards whereever possible. This is not restricted to 
84: agent standards.
85: Most important in the field of agent standards are the communication standards, which 
86: should enable interoperability between different agent platforms. These standards have been 
87: released by the
88: [Foundation for Intelligent Physical Agents (FIPA)>http://www.fipa.org/], 
89: which are commonly referred to as "the FIPA standard". 
90: As shown in the figure, the FIPA standard specifies an agent platform architecture, 
91: which defines services such as agent management and a directory facilitator. This architecture
92: enables agents to communicate using a common agent communication language.
93: To achieve FIPA-compliancy, Jadex can be used with the [JADE Agent Framework>http://jade.cselt.it/],
94: an open source development by the [Telecom Italia Lab>http://www.telecomitalialab.com/].
95: JADE provides the platform architecture and the core
96: services and message transport mechanisms as required by the FIPA specifications.
97: </p>
98: </td>
99: <td>
100: {image:agentmanagement.png}
101: </td>
102: </tr>
103: </tbody>
104: </table>
105: 
106: 1.1 Goal Oriented Agents
107: 
108: The internal state and decision process of agents is therefore modelled
109: in an intuitive manner following the notion of *mental attitudes*.
110: Goal orientation means that, instead of directly requesting the agents to perform
111: certain actions, the developer can define more abstract goals for the agents,
112: thereby providing a certain degree of flexibility on how to achieve the goals.
113: The BDI Model, based on the mental attitudes belief, desire and intention,
114: was first introduced as a philosophical model for modelling rational (human) agents,
115: but later adopted and transformed into an execution model for software agents,
116: based on the notion of beliefs, goals, and plans.
117: Jadex incorporates this model by introducing *beliefs*,
118: *goals* and *plans* as first class concepts that can be created an
119: manipulated inside the agent. In Jadex, agents have beliefs, which can be any
120: kind of Java object and are stored in a belief base. Goals come in different
121: flavors and allow to describe what an agent should achieve in a declarative manner.
122: Goals do not include information about how it can be fulfilled. This kind of 
123: knowledge is encoded in plans. Hence, to achieve its goals the agent executes plans, 
124: which are procedural recipes coded in Java.
125: 
126: 1.1 Framework
127: 
128: Programming Jadex agents can be done by using the framework *API* and
129: possibly predefined *reusable generic functionality* in form of capabilities.
130: The API provides access to the Jadex concepts when programming plans.
131: Plans are plain Java classes, extending a specific abstract class, which
132: provides useful methods e.g. for sending messages, dispatching sub goals or waiting for events.
133: Plans able to read and alter the beliefs of the agent using the API of the belief base.
134: A special feature of Jadex is that in addition to directly retrieving stored facts,
135: an intuitive *OQL-like query language* allows to formulate arbitrary complex expressions
136: using the objects contained in the belief base. 
137: In addition to the plans coded in Java, the developer provides an *XML based
138: Agent Definition File (ADF)*, which specifies the initial beliefs, goals,
139: and plans of an agent. The Jadex runtime engine reads this file to instantiate
140: an agent model, and executes the agent by keeping track of its goals while
141: continuously selecting and executing plan steps, based on internal events
142: and messages from other agents. Jadex is supplied with some predefined
143: functionality e.g. to access a directory facilitator service.
144: The functionality, coded in separate plans, is composed in reusable agent
145: modules called *capabilities*, described in a format similar to the ADF,
146: and can easily be plugged into existing agents.
147: \\
148: An important quality aspect of any development environment is the available tool 
149: support. As Jadex uses the standard programming languages XML and Java
150: existing IDEs like eclipse can be used for programming agents as well.
151: Furthermore, Jadex offers a complete runtime tool suite for managing,
152: testing and debugging agents. Basis of this suite is the Jadex Control
153: Center tool (JCC), which is the access point for all the tools (realized
154: as plugins). Currently the following tools are available:
155: * *Starter* for starting and stopping agents and viewing all agents currently living on the platform
156: * *Directory Facilitator* for viewing registered services of agents
157: * *Conversation Center* for directly sending messages to agents
158: * *Comanalyer* for sniffing and displaying message-based interactions
159: * *Test Center* for executing agent-based unit tests 
160: * *Simulation Control Center* for executing applications in real-time or simulation modes (time- or event-driven)
161: * *Introspector* for introspecting agents and executing them stepwise
162: * *Library Tool* for managing the Java classpath at runtime by adding/removing libraries such as jar-files
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