org.arl.fjage

Class Behavior

java.lang.Object

org.arl.fjage.Behavior

All Implemented Interfaces:

java.lang.Comparable<Behavior>

Direct Known Subclasses:

BackoffBehavior, CyclicBehavior, FSMBehavior, MessageBehavior, OneShotBehavior, PoissonBehavior, TickerBehavior, WakerBehavior

public class Behavior
extends java.lang.Object
implements java.lang.Comparable<Behavior>

Base class for agent behaviors. Commonly used behaviors are provided by subclasses:

• CyclicBehavior for continuous behaviors
• OneShotBehavior for one time behaviors
• WakerBehavior for behaviors to be executed once after a specified period
• TickerBehavior for behaviors to be executed periodically
• BackoffBehavior for retry or backoff timeouts
• PoissonBehavior for simulating Poisson arrival processes
• MessageBehavior for behaviors to process incoming messages
• TestBehavior for unit testing
• FSMBehavior for implementing finite state machines

Additionally, developers may create their own behaviors by extending this class or one of its subclasses.

Field Summary

Fields

Modifier and Type	Field and Description
protected Callback	action If this field is not null, the default action() method calls it.
protected Agent	agent Agent owning this behavior.
protected java.util.logging.Logger	log Logger for the behavior to log messages to.

Constructor Summary

Constructors

Constructor and Description
Behavior()

Method Summary

Modifier and Type	Method and Description
void	action() This method is repeatedly called during the life of a behavior.
AgentID	agent(java.lang.String name) Convenience method to create an owned agent id for the named agent.
AgentID	agentForService(java.lang.Enum<?> service) Convenience method to find an agent that provides a named service.
AgentID	agentForService(java.lang.String service) Convenience method to find an agent that provides a named service.
AgentID[]	agentsForService(java.lang.Enum<?> service) Convenience method to find all agents that provides a named service.
AgentID[]	agentsForService(java.lang.String service) Convenience method to find all agents that provides a named service.
void	block() Blocks the behavior.
void	block(long millis) Blocks the behavior for a specified period of time.
int	compareTo(Behavior obj) Implements natural ordering based on behavior priority.
boolean	done() This method should return true if the behavior is completed, false otherwise.
int	getPriority() This method should return a number that denotes the priority of a behavior.
boolean	isBlocked() Returns true if the behavior is blocked, false otherwise.
void	onEnd() This method is called when a behavior is completed.
void	onStart() This method is called when a behavior is added to an agent.
void	println(java.lang.String msg) Log a message at an INFO level.
void	reset() Resets a behavior to its initial state.
void	restart() Unblocks the behavior if it was blocked.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

agent

protected Agent agent

Agent owning this behavior. This attribute should not be modified by the behavior.

log

protected java.util.logging.Logger log

Logger for the behavior to log messages to. This logger defaults to the same logger as the owning agent's logger.

action

protected Callback action

If this field is not null, the default action() method calls it.

Constructor Detail

Behavior

public Behavior()

Method Detail

onStart

public void onStart()

This method is called when a behavior is added to an agent. A behavior may customize this by overriding it.

onEnd

public void onEnd()

This method is called when a behavior is completed. A behavior may customize this by overriding it.

action

public void action()

This method is repeatedly called during the life of a behavior. A behavior may override this to provide appropriate functionality.

done

public boolean done()

This method should return true if the behavior is completed, false otherwise. A behavior should override this.

Returns:

true if behavior is completed, false otherwise.

getPriority

public int getPriority()

This method should return a number that denotes the priority of a behavior. By default, the priority is 0. Behaviors with lower priority values are executed before behaviors with higher priority values.

Returns:

priority value

compareTo

public int compareTo(Behavior obj)

Implements natural ordering based on behavior priority. Note: this class has a natural ordering that is inconsistent with equals.

Specified by:

compareTo in interface java.lang.Comparable<Behavior>

block

public void block()

Blocks the behavior. Blocking a behavior simply puts it in a blocked state as soon as the current action() is completed. In a blocked state, the action() method is no longer called until the behavior is unblocked by a call to restart(). Unlike Agent.block(), this method is non-blocking.

block

public void block(long millis)

Blocks the behavior for a specified period of time. Blocking a behavior simply puts it in a blocked state as soon as the current action() is completed. In a blocked state, the action() method is no longer called until the behavior is unblocked after the specified period of time or by a call to restart(). Unlike Agent.block(), this method is non-blocking.

Parameters:

millis - number of milliseconds before the behavior should be unblocked.

restart

public void restart()

Unblocks the behavior if it was blocked.

See Also:

block()

isBlocked

public boolean isBlocked()

Returns true if the behavior is blocked, false otherwise.

Returns:

true if the behavior is blocked, false otherwise.

reset

public void reset()

Resets a behavior to its initial state.

agent

public AgentID agent(java.lang.String name)

Convenience method to create an owned agent id for the named agent.

Returns:

agent id for the named agent.

agentForService

public AgentID agentForService(java.lang.String service)

Convenience method to find an agent that provides a named service. If multiple agents are registered to provide a given service, any of the agents' id may be returned.

Parameters:

service - the named service of interest.

Returns:

an agent id for an agent that provides the service.

agentForService

public AgentID agentForService(java.lang.Enum<?> service)

Convenience method to find an agent that provides a named service. If multiple agents are registered to provide a given service, any of the agents' id may be returned.

Parameters:

service - the named service of interest.

Returns:

an agent id for an agent that provides the service.

agentsForService

public AgentID[] agentsForService(java.lang.String service)

Convenience method to find all agents that provides a named service.

Parameters:

service - the named service of interest.

Returns:

an array of agent ids representing all agent that provide the service.

agentsForService

public AgentID[] agentsForService(java.lang.Enum<?> service)

Convenience method to find all agents that provides a named service.

Parameters:

service - the named service of interest.

Returns:

an array of agent ids representing all agent that provide the service.

println

public void println(java.lang.String msg)

Log a message at an INFO level.

Parameters:

msg - message to log.