001 /***************************************************************************** 002 * Copyright (C) PicoContainer Organization. All rights reserved. * 003 * ------------------------------------------------------------------------- * 004 * The software in this package is published under the terms of the BSD * 005 * style license a copy of which has been included with this distribution in * 006 * the LICENSE.txt file. * 007 * * 008 * Original code by Paul Hammant * 009 *****************************************************************************/ 010 package org.picocontainer.alternatives; 011 012 import java.io.Serializable; 013 import java.util.Collections; 014 import java.util.Collection; 015 import java.util.List; 016 import org.picocontainer.PicoContainer; 017 import org.picocontainer.PicoVisitor; 018 import org.picocontainer.ComponentAdapter; 019 020 /** 021 * empty pico container serving as recoil damper in situations where you 022 * do not like to check whether container reference suplpied to you 023 * is null or not 024 * @author Konstantin Pribluda 025 * @since 1.1 026 */ 027 public class EmptyPicoContainer implements PicoContainer, Serializable { 028 public Object getComponentInstance(Object componentKey) { 029 return null; 030 } 031 032 public Object getComponentInstanceOfType(Class componentType) { 033 return null; 034 } 035 public List getComponentInstances() { 036 return Collections.EMPTY_LIST; 037 } 038 039 public PicoContainer getParent() { 040 return null; 041 } 042 public ComponentAdapter getComponentAdapter(Object componentKey) { 043 return null; 044 } 045 046 public ComponentAdapter getComponentAdapterOfType(Class componentType) { 047 return null; 048 } 049 050 public Collection getComponentAdapters() { 051 return Collections.EMPTY_LIST; 052 } 053 054 public List getComponentAdaptersOfType(Class componentType) { 055 return Collections.EMPTY_LIST; 056 } 057 058 public void verify() {} 059 060 public void accept(PicoVisitor visitor) { } 061 062 public List getComponentInstancesOfType(Class componentType) { 063 return Collections.EMPTY_LIST; 064 } 065 066 public void start() {} 067 public void stop() {} 068 public void dispose() {} 069 }