org.macroing.cit.ioc.component

Class Component

java.lang.Object

org.macroing.cit.ioc.component.Component

public abstract class Component
extends java.lang.Object

A Component is a component in the sense of Inversion of Control (IoC).

Its primary responsibility is to govern the life-cycle of a modular component. It can be started and it can be stopped.

The order in which Components are started and stopped, is the responsibility of the ComponentLoaders that loads them.

This class is not thread-safe.

Since:

1.0.0

Author:

Jörgen Lundgren

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Component() Constructs a new Component instance.
protected	Component(java.lang.String name) Constructs a new Component instance.
protected	Component(java.lang.String name, java.lang.String id) Constructs a new Component instance.

Method Summary

Modifier and Type	Method and Description
protected abstract void	doStart() Starts this Component instance, if not already running.
protected abstract void	doStop() Stops this Component instance, if it's currently running.
boolean	equals(java.lang.Object object) Compares this Component instance to object for equality.
java.lang.String	getId() Returns the ID of this Component instance.
java.lang.String	getName() Returns the name of this Component instance.
int	hashCode() Returns a hash-code for this Component instance.
boolean	isRunning() Returns true if, and only if, this Component instance is currently running, false otherwise.
void	start() Starts this Component instance, if not already running.
void	stop() Stops this Component instance, if it's currently running.

Methods inherited from class java.lang.Object

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

Constructor Detail

Component

protected Component()

Constructs a new Component instance.

Both name and ID will be set to the fully qualified name of its Class.

This new Component instance will not be started automatically.

Component

protected Component(java.lang.String name)

Constructs a new Component instance.

Sets the name to name and ID to the fully qualified name of its Class.

If name is null, a NullPointerException will be thrown.

This new Component instance will not be started automatically.

Parameters:

name - the name of this Component instance

Throws:

java.lang.NullPointerException - thrown if, and only if, name is null

Component

protected Component(java.lang.String name,
                    java.lang.String id)

Constructs a new Component instance.

Sets the name to name and ID to id.

If either name or id are null, a NullPointerException will be thrown.

This new Component instance will not be started automatically.

Parameters:

name - the name of this Component instance

id - the ID of this Component instance

Throws:

java.lang.NullPointerException - thrown if, and only if, either name or id are null

Method Detail

equals

public final boolean equals(java.lang.Object object)

Compares this Component instance to object for equality.

Returns true if, and only if, this Component instance is equal to object, false otherwise.

Two Components are said to be equal if, and only if, both of their ID are exactly the same.

Overrides:

equals in class java.lang.Object

Parameters:

object - the Object to compare this Component instance to for equality

Returns:

true if, and only if, this Component instance is equal to object, false otherwise

isRunning

public final boolean isRunning()

Returns true if, and only if, this Component instance is currently running, false otherwise.

Returns:

true if, and only if, this Component instance is currently running, false otherwise

hashCode

public final int hashCode()

Returns a hash-code for this Component instance.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash-code for this Component instance

getId

public final java.lang.String getId()

Returns the ID of this Component instance.

The default ID is the fully qualified name of its Class.

The ID of a Component must, in contrast to its name, be unique.

Returns:

the ID of this Component instance

getName

public final java.lang.String getName()

Returns the name of this Component instance.

The default name is the same as its ID.

The name of a Component should preferably be easy to remember for any user of the modular application you're creating. Two Components may have the same name, although we do not encourage that. But we do encourage a name that is internationalized.

Returns:

the name of this Component instance

start

public final void start()

Starts this Component instance, if not already running.

If this Component was not running prior to calling this method, its doStart() method will be called.

stop

public final void stop()

Stops this Component instance, if it's currently running.

If this Component was running prior to calling this method, its doStop() method will be called.

doStart

protected abstract void doStart()

Starts this Component instance, if not already running.

This method will be called by the start() method, if this Component instance is not already running.

This method is intended to be overridden by subclasses to handle their own start logic.

doStop

protected abstract void doStop()

Stops this Component instance, if it's currently running.

This method will be called by the stop() method, if this Component instance is currently running.

This method is intended to be overridden by subclasses to handle their own stop logic.