de.lmu.ifi.dbs.elki.utilities
Class HandlerList<H>

java.lang.Object
  de.lmu.ifi.dbs.elki.utilities.HandlerList<H>

Type Parameters:

H - Parent class/interface for all handlers

public final class HandlerList<H>
extends Object

Manages a list of handlers for objects. Handlers are appended to a list in sequence, and when querying, the last added handler will be used where the query object can be cast to the handlers restriction class.

Field Summary

private ArrayList<Pair<Class<?>,H>>

handlers List with registered Handlers.

Constructor Summary

HandlerList()

Method Summary

H	getHandler(Object o) Find a matching handler for the given object
void	insertHandler(Class<?> restrictionClass, H handler) Insert a handler to the beginning of the stack.

Methods inherited from class java.lang.Object

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

Field Detail

handlers

private ArrayList<Pair<Class<?>,H>> handlers

List with registered Handlers. The list is kept in backwards order, that is the later entrys take precedence.

Constructor Detail

HandlerList

public HandlerList()

Method Detail

insertHandler

public void insertHandler(Class<?> restrictionClass,
                          H handler)

Insert a handler to the beginning of the stack.

Parameters:

restrictionClass - restriction class

handler - handler

getHandler

public H getHandler(Object o)

Find a matching handler for the given object

Parameters:

o - object to find handler for

Returns:

handler for the object. null if no handler was found.