/*
* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle 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 2 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
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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*/
package com.sun.tools.visualvm.core.datasupport;
import java.util.Collections;
import java.util.Set;
/**
* An event containing information about added, removed and actual items of a monitored repository.
*
* @author Tomas Hurka
*/
public final class DataChangeEvent<X> {
private static final Set EMPTY_SET = Collections.EMPTY_SET;
private Set<X> current;
private Set<X> added;
private Set<X> removed;
/**
* Creates new DataChangeEvent.
*
* @param current actual items of a monitored repository,
* @param added items recently added to a monitored repository,
* @param removed items recently removed from a monitored repository.
*/
public DataChangeEvent(Set<X> current, Set<X> added, Set<X> removed) {
this.current = current == null ? EMPTY_SET : current;
this.added = added == null ? EMPTY_SET : added;
this.removed = removed == null ? EMPTY_SET : removed;
}
/**
* Returns actual items of a monitored repository.
*
* @return actual items of a monitored repository.
*/
public Set<X> getCurrent() {
return current;
}
/**
* Returns items recently added to a monitored repository,
*
* @return items recently added to a monitored repository,
*/
public Set<X> getAdded() {
return added;
}
/**
* Returns items recently removed from a monitored repository.
*
* @return items recently removed from a monitored repository.
*/
public Set<X> getRemoved() {
return removed;
}
}