/*******************************************************************************
* Copyright (c) 2000, 2004 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.rubypeople.rdt.internal.core.buffer;
import org.rubypeople.rdt.core.IBuffer;
import org.rubypeople.rdt.internal.core.Openable;
/**
* An LRU cache of <code>IBuffers</code>.
*/
public class BufferCache extends OverflowingLRUCache {
/**
* Constructs a new buffer cache of the given size.
*/
public BufferCache(int size) {
super(size);
}
/**
* Constructs a new buffer cache of the given size.
*/
public BufferCache(int size, int overflow) {
super(size, overflow);
}
/**
* Returns true if the buffer is successfully closed and
* removed from the cache, otherwise false.
*
* <p>NOTE: this triggers an external removal of this buffer
* by closing the buffer.
*/
protected boolean close(LRUCacheEntry entry) {
IBuffer buffer= (IBuffer) entry._fValue;
// prevent buffer that have unsaved changes or working copy buffer to be removed
// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=39311
if (!((Openable)buffer.getOwner()).canBufferBeRemovedFromCache(buffer)) {
return false;
}
buffer.close();
return true;
}
/**
* Returns a new instance of the reciever.
*/
protected LRUCache newInstance(int size, int overflow) {
return new BufferCache(size, overflow);
}
}