/*******************************************************************************
* Copyright (c) 2005, 2008 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.ltk.internal.core.refactoring.history;
import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import org.eclipse.core.runtime.Assert;
import org.eclipse.ltk.core.refactoring.RefactoringDescriptorProxy;
import org.eclipse.ltk.core.refactoring.history.RefactoringHistory;
/**
* Default implementation of a refactoring history.
*
* @since 3.2
*/
public final class RefactoringHistoryImplementation extends RefactoringHistory {
/**
* Returns a hash code value for the array
*
* @param array
* the array to create a hash code value for
* @return a hash code value for the array
*/
private static int hashCode(final Object[] array) {
if (array == null)
return 0;
int result= 1;
for (int index= 0; index < array.length; index++)
result= 31 * result + (array[index] == null ? 0 : array[index].hashCode());
return result;
}
/** The refactoring descriptor proxies */
private final RefactoringDescriptorProxy[] fDescriptorProxies;
/** Is the refactoring history already sorted? */
private boolean fSorted= false;
/**
* Creates a new refactoring history implementation.
*
* @param proxies
* the refactoring descriptor proxies
*/
public RefactoringHistoryImplementation(final RefactoringDescriptorProxy[] proxies) {
Assert.isNotNull(proxies);
fDescriptorProxies= new RefactoringDescriptorProxy[proxies.length];
System.arraycopy(proxies, 0, fDescriptorProxies, 0, proxies.length);
}
/**
* {@inheritDoc}
*/
public boolean equals(final Object object) {
if (this == object)
return true;
if (object == null)
return false;
if (getClass() != object.getClass())
return false;
final RefactoringHistoryImplementation other= (RefactoringHistoryImplementation) object;
if (!Arrays.equals(getDescriptors(), other.getDescriptors()))
return false;
return true;
}
/**
* Returns the descriptor proxies, in no particular order.
*
* @return the descriptor proxies
*/
RefactoringDescriptorProxy[] getDescriptorProxies() {
return fDescriptorProxies;
}
/**
* {@inheritDoc}
*/
public RefactoringDescriptorProxy[] getDescriptors() {
if (!fSorted && fDescriptorProxies.length > 1)
RefactoringHistoryManager.sortRefactoringDescriptorsDescending(fDescriptorProxies);
fSorted= true;
final RefactoringDescriptorProxy[] proxies= new RefactoringDescriptorProxy[fDescriptorProxies.length];
System.arraycopy(fDescriptorProxies, 0, proxies, 0, fDescriptorProxies.length);
return proxies;
}
/**
* {@inheritDoc}
*/
public int hashCode() {
return 31 * RefactoringHistoryImplementation.hashCode(getDescriptors());
}
/**
* {@inheritDoc}
*/
public boolean isEmpty() {
return fDescriptorProxies.length == 0;
}
/**
* {@inheritDoc}
*/
public RefactoringHistory removeAll(final RefactoringHistory history) {
final Set existing= new LinkedHashSet(Arrays.asList(fDescriptorProxies));
final Set other= new HashSet(Arrays.asList(history.getDescriptors()));
existing.removeAll(other);
final RefactoringDescriptorProxy[] proxies= new RefactoringDescriptorProxy[existing.size()];
existing.toArray(proxies);
return new RefactoringHistoryImplementation(proxies);
}
/**
* {@inheritDoc}
*/
public String toString() {
final StringBuffer buffer= new StringBuffer(256);
buffer.append(getClass().getName());
buffer.append("[descriptors="); //$NON-NLS-1$
buffer.append(getDescriptors().toString());
buffer.append(']');
return buffer.toString();
}
}