com.cedarsoft.registry.DefaultRegistry Maven / Gradle / Ivy
/**
* Copyright (C) cedarsoft GmbH.
*
* Licensed under the GNU General Public License version 3 (the "License")
* with Classpath Exception; you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.cedarsoft.org/gpl3ce
* (GPL 3 with Classpath Exception)
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 3 only, as
* published by the Free Software Foundation. cedarsoft GmbH designates this
* particular file as subject to the "Classpath" exception as provided
* by cedarsoft GmbH in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 3 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 3 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact cedarsoft GmbH, 72810 Gomaringen, Germany,
* or visit www.cedarsoft.com if you need additional information or
* have any questions.
*/
package com.cedarsoft.registry;
import com.cedarsoft.commons.Converter;
import com.cedarsoft.exceptions.NotFoundException;
import com.cedarsoft.exceptions.StillContainedException;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.TreeSet;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
* DefaultRegistry class.
*
* @param the type that is stored within this registry
* @author Johannes Schneider ([email protected])
*/
public class DefaultRegistry implements Registry {
@Nonnull
protected final List storedObjects = new ArrayList();
@Nonnull
protected final ReadWriteLock lock = new ReentrantReadWriteLock();
/**
* This comparator may optionally be set to ensure the registry only contains unique values
*/
@Nullable
protected final Comparator comparator;
/**
* Creates an empty registry
*/
public DefaultRegistry() {
comparator = null;
}
/**
* Creates a registry with containing the given objects.
* No comparator is set
*
* @param storedObjects the stored objects
*/
public DefaultRegistry( @Nonnull Collection storedObjects ) {
this( storedObjects, null );
}
/**
* Creates an empty registry with the given (optional) comparator
*
* @param comparator the comparator
*/
public DefaultRegistry( @Nullable Comparator comparator ) {
this.comparator = comparator;
}
/**
* Creates a new registry
*
* @param storedObjects the initially stored objects
* @param comparator the (optional) comparator
*/
public DefaultRegistry( @Nonnull Collection storedObjects, @Nullable Comparator comparator ) throws StillContainedException {
this.comparator = comparator;
//todo, really necessary???
if ( comparator != null ) {
Collection set = new TreeSet( comparator );
set.addAll( storedObjects );
if ( storedObjects.size() != set.size() ) {
throw new StillContainedException( "The stored objects collections contains duplicate entries" );
}
}
this.storedObjects.addAll( storedObjects );
}
@Override
@Nonnull
public List getStoredObjects() {
lock.readLock().lock();
try {
return Collections.unmodifiableList( storedObjects );
} finally {
lock.readLock().unlock();
}
}
@Override
@Nullable
public T findStoredObject( @Nonnull Matcher matcher ) {
lock.readLock().lock();
try {
for ( T object : storedObjects ) {
if ( matcher.matches( object ) ) {
return object;
}
}
return null;
} finally {
lock.readLock().unlock();
}
}
/**
* findStoredObject
*
* @param matcher a Matcher object.
* @param notFoundMessage a String object.
* @return a T object.
*/
@Override
@Nonnull
public T findStoredObject( @Nonnull Matcher matcher, @Nonnull String notFoundMessage ) throws NotFoundException {
T found = findStoredObject( matcher );
if ( found == null ) {
throw new NotFoundException( notFoundMessage );
}
return found;
}
@Override
@Nonnull
public List findStoredObjects( @Nonnull Matcher matcher ) {
lock.readLock().lock();
try {
List found = new ArrayList();
for ( T object : storedObjects ) {
if ( matcher.matches( object ) ) {
found.add( object );
}
}
return found;
} finally {
lock.readLock().unlock();
}
}
@Override
@Nonnull
public List findStoredObjects( @Nonnull Matcher matcher, @Nonnull Converter converter ) {
lock.readLock().lock();
try {
List found = new ArrayList();
for ( T object : storedObjects ) {
if ( matcher.matches( object ) ) {
found.add( converter.convert( object ) );
}
}
return found;
} finally {
lock.readLock().unlock();
}
}
/**
* {@inheritDoc}
*
* Stores the object within the registry
*/
@Override
public void store( @Nonnull T object ) throws StillContainedException {
lock.writeLock().lock();
try {
if ( comparator != null ) {
for ( T storedObject : storedObjects ) {
if ( comparator.compare( storedObject, object ) == 0 ) {
throw new StillContainedException( object );
}
}
}
storedObjects.add( object );
for ( Listener listener : new ArrayList>( listeners ) ) {
listener.objectStored( object );
}
} finally {
lock.writeLock().unlock();
}
}
@Override
public void updated( @Nonnull T object ) throws NotFoundException {
lock.writeLock().lock();
try {
for ( Listener listener : new ArrayList>( listeners ) ) {
listener.objectUpdated( object );
}
} finally {
lock.writeLock().unlock();
}
}
@Override
public void remove( @Nonnull T object ) throws NotFoundException {
remove( object, "Cannot remove: Not found <" + object + ">" );
}
@Override
public void remove( @Nonnull T object, @Nonnull String removeMessage ) throws NotFoundException {
lock.writeLock().lock();
try {
if ( !storedObjects.remove( object ) ) {
throw new NotFoundException( removeMessage );
}
for ( Listener listener : new ArrayList>( listeners ) ) {
listener.objectRemoved( object );
}
} finally {
lock.writeLock().unlock();
}
}
@Override
@Nullable
public Comparator getComparator() {
return comparator;
}
@Override
public boolean containsOnlyUniqueElements() {
return comparator != null;
}
@Nonnull
protected final List> listeners = new ArrayList>();
@Override
public void addListener( @Nonnull Listener listener ) {
lock.writeLock().lock();
try {
this.listeners.add( listener );
} finally {
lock.writeLock().unlock();
}
}
@Override
public void removeListener( @Nonnull Listener listener ) {
lock.writeLock().lock();
try {
this.listeners.remove( listener );
} finally {
lock.writeLock().unlock();
}
}
}