org.apache.commons.clazz.common
Class GroupClazzLoader

java.lang.Object
  org.apache.commons.clazz.ClazzLoader
      org.apache.commons.clazz.common.GroupClazzLoader

Direct Known Subclasses:

BeanGroupClazzLoader, ReflectedGroupClazzLoader

public class GroupClazzLoader

extends org.apache.commons.clazz.ClazzLoader

Aggregates multiple ClazzLoaders, which are invoked one after another according to the ChainOfResponsibility pattern. Note that member clazz loaders are invoked in the order reverse to the order they were added.

Version:

$Id: GroupClazzLoader.java,v 1.6 2004/02/19 23:58:40 scolebourne Exp $

Author:

Dmitri Plotnikov

Field Summary

protected ArrayList

loaders List of member loaders.

Constructor Summary

GroupClazzLoader(org.apache.commons.clazz.ModelClazzLoader modelClazzLoader)

Method Summary

void	addClazzLoader(org.apache.commons.clazz.ClazzLoader loader) Adds a ClazzLoader to the group.
boolean	canAddClazzLoader(org.apache.commons.clazz.ClazzLoader loader) Returns true if the supplied loader "belongs" in the group and can be added to it.
org.apache.commons.clazz.Clazz	defineClazz(String name, Class clazzClass, Class instanceClass) Defines a new Clazz with the supplied name.
org.apache.commons.clazz.Clazz	getClazzForName(String name) Given a Clazz name, produces the corresponding Clazz by invoking member loaders one by one until the clazz is found.
List	getClazzLoaders() Returns all clazz loaders registered with this group, in the order of priority
String	getClazzName(Object instance) Returns the clazz name for the supplied instance.
boolean	isMember(Object instance) Returns true iff this group has a member loader that has or can construct a Clazz for the supplied instance.

Methods inherited from class org.apache.commons.clazz.ClazzLoader

enableLogging, getClazz, getModel, getModelClazzLoader, isLoggingEnabled

Methods inherited from class java.lang.Object

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

Field Detail

loaders

protected ArrayList loaders

List of member loaders. Note that the list is always iterated in the reverse direction, so the loaded add last is the one invoked first.

Constructor Detail

GroupClazzLoader

public GroupClazzLoader(org.apache.commons.clazz.ModelClazzLoader modelClazzLoader)

Method Detail

canAddClazzLoader

public boolean canAddClazzLoader(org.apache.commons.clazz.ClazzLoader loader)

Returns true if the supplied loader "belongs" in the group and can be added to it. The default implementation returns true.

addClazzLoader

public void addClazzLoader(org.apache.commons.clazz.ClazzLoader loader)

Adds a ClazzLoader to the group. ClazzLoaders added last are invoked first. Before the group adds the loader to itself, it checks if any of its members are groups themselves and, if so, tries to add the new loader to those subgroups.

isMember

public boolean isMember(Object instance)

Returns true iff this group has a member loader that has or can construct a Clazz for the supplied instance.

getClazzName

public String getClazzName(Object instance)

Description copied from class: org.apache.commons.clazz.ClazzLoader

Returns the clazz name for the supplied instance. Returns null if it cannot produce a clazz name for the instance.

getClazzForName

public org.apache.commons.clazz.Clazz getClazzForName(String name)

Given a Clazz name, produces the corresponding Clazz by invoking member loaders one by one until the clazz is found.

defineClazz

public org.apache.commons.clazz.Clazz defineClazz(String name,
                                                  Class clazzClass,
                                                  Class instanceClass)

Description copied from class: org.apache.commons.clazz.ClazzLoader

Defines a new Clazz with the supplied name. If it cannot define a clazz of the supplied type or if it cannot define clazzes at all, returns null.

Parameters:

name - the name of the clazz, should be unique within the scope of the top-level ClazzLoader

clazzClass - the Class of the Clazz that this method needs to produce.

instanceClass - the Class of the instances the new Clazz will be able to create using the newInstance() method.

Returns:

Clazz

See Also:

ClazzLoader.defineClazz(String, Class, Class)

getClazzLoaders

public List getClazzLoaders()

Returns all clazz loaders registered with this group, in the order of priority