Package org.gcube.informationsystem.discovery

Class Discovery<E extends Element>

java.lang.Object

org.gcube.informationsystem.discovery.Discovery<E>

Type Parameters:

E - The root element type for the discovery process.

public class Discovery<E extends Element>
extends Object

A generic class for discovering all subtypes of a given root element within a set of packages.

Author:

Luca Frosini (ISTI - CNR)

Field Summary

Fields

Modifier and Type	Field	Description
protected boolean	discovered	Whether the discovery process has been completed.
protected List<DiscoveredElementAction<Element>>	discoveredElementActions	The list of actions to be executed on each discovered element.
protected List<Class<E>>	discoveredElements	The list of discovered element classes.
static org.slf4j.Logger	logger	The logger for this class.
protected Set<Package>	packages	The set of packages to be scanned.
protected Class<E>	root	The root class of the element hierarchy to discover.
protected Set<Class<? extends E>>	stopClasses	A set of classes where the discovery process should stop.

Constructor Summary

Constructors

Constructor	Description
Discovery(Class<E> root)	Constructs a new Discovery instance for the given root type.

Method Summary

Modifier and Type	Method	Description
protected void	add(Class<E> clz)	Adds a class to the list of discovered elements and notifies any registered actions.
void	addDiscoveredElementActions(DiscoveredElementAction<Element> discoveredElementAction)	Adds a DiscoveredElementAction to be executed on each discovered element.
void	addPackage(Package p)	Adds a package to be scanned during discovery.
void	addPackages(Collection<Package> packages)	Adds a collection of packages to be scanned.
void	addStopClass(Class<? extends E> stopClass)	Adds a class to the set of stop classes for the discovery process.
protected void	analizeElement(Class<E> clz)	Recursively analyzes a class to find subtypes of the root element.
void	discover()	Starts the discovery process, scanning all registered packages.
void	executeDiscoveredElementActions(DiscoveredElementAction<Element> discoveredElementAction)	Executes a given DiscoveredElementAction on all already discovered elements.
List<Class<E>>	getDiscoveredElements()	Returns the list of discovered element classes.

Methods inherited from class java.lang.Object

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

Field Detail

logger

public static org.slf4j.Logger logger

The logger for this class.

root

protected final Class<E extends Element> root

The root class of the element hierarchy to discover.

packages

protected final Set<Package> packages

The set of packages to be scanned.

discoveredElements

protected final List<Class<E extends Element>> discoveredElements

The list of discovered element classes.

discoveredElementActions

protected final List<DiscoveredElementAction<Element>> discoveredElementActions

The list of actions to be executed on each discovered element.

stopClasses

protected Set<Class<? extends E extends Element>> stopClasses

A set of classes where the discovery process should stop. It is mainly used to avoid analyzing Model Classes (Resource, Facet, IsRelatedTo, ConsistsOf, Property) when discoverying lower level classes. As an example when when root is EntityElement the discovery must stop to Resource and Facet classes which hierarchy is not interesting for that level and will be discovered by using Resource and Facet as root classes respectively.

discovered

protected boolean discovered

Whether the discovery process has been completed.

Constructor Detail

Discovery

public Discovery(Class<E> root)
          throws Exception

Constructs a new Discovery instance for the given root type.

Parameters:

root - The root class of the element hierarchy to discover.

Throws:

Exception - if an error occurs during initialization.

Method Detail

addStopClass

public void addStopClass(Class<? extends E> stopClass)

Adds a class to the set of stop classes for the discovery process. The stop classes are not analyzed or added to the discovered elements.

Parameters:

stopClass - The class to add as a stop class.

getDiscoveredElements

public List<Class<E>> getDiscoveredElements()

Returns the list of discovered element classes.

Returns:

A list of discovered classes.

addDiscoveredElementActions

public void addDiscoveredElementActions(DiscoveredElementAction<Element> discoveredElementAction)
                                 throws Exception

Adds a DiscoveredElementAction to be executed on each discovered element.

Parameters:

discoveredElementAction - The action to add.

Throws:

Exception - if an error occurs while analyzing existing elements.

executeDiscoveredElementActions

public void executeDiscoveredElementActions(DiscoveredElementAction<Element> discoveredElementAction)
                                     throws Exception

Executes a given DiscoveredElementAction on all already discovered elements.

Parameters:

discoveredElementAction - The action to execute.

Throws:

Exception - if an error occurs during execution.

addPackage

public void addPackage(Package p)

Adds a package to be scanned during discovery.

Parameters:

p - The package to add.

addPackages

public void addPackages(Collection<Package> packages)

Adds a collection of packages to be scanned.

Parameters:

packages - The collection of packages.

add

protected void add(Class<E> clz)
            throws Exception

Adds a class to the list of discovered elements and notifies any registered actions.

Parameters:

clz - The class to add.

Throws:

Exception - if an error occurs in a DiscoveredElementAction.

analizeElement

protected void analizeElement(Class<E> clz)
                       throws Exception

Recursively analyzes a class to find subtypes of the root element.

Parameters:

clz - The class to analyze.

Throws:

Exception - if an error occurs during analysis.

discover

public void discover()
              throws Exception

Starts the discovery process, scanning all registered packages.

Throws:

Exception - if an error occurs during discovery.