/*******************************************************************************
* Copyright (c) 2000, 2006 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.ui.internal;
import java.util.ArrayList;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IMemento;
import org.eclipse.ui.INavigationLocation;
import org.eclipse.ui.INavigationLocationProvider;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.XMLMemento;
/*
* Wraps the INavigationLocation and keeps editor info.
*/
public class NavigationHistoryEntry {
private IWorkbenchPage page;
NavigationHistoryEditorInfo editorInfo;
String historyText;
/* Both may be set at the same time. */
INavigationLocation location;
private IMemento locationMemento;
/**
* Constructs a new HistoryEntry and intializes its editor input and editor id.
*/
public NavigationHistoryEntry(NavigationHistoryEditorInfo editorInfo,
IWorkbenchPage page, IEditorPart part, INavigationLocation location) {
this.editorInfo = editorInfo;
this.page = page;
this.location = location;
if (location != null) {
historyText = location.getText();
}
// ensure that the historyText is initialized to something
if (historyText == null || historyText.length() == 0) {
if (part != null) {
historyText = part.getTitle();
}
}
}
/**
* Restores the state of the entry and the location if needed and then
* restores the location.
*/
void restoreLocation() {
if (editorInfo.editorInput != null && editorInfo.editorID != null) {
try {
IEditorPart editor = page.openEditor(editorInfo.editorInput,
editorInfo.editorID, true);
if (location == null) {
if (editor instanceof INavigationLocationProvider) {
location = ((INavigationLocationProvider) editor)
.createEmptyNavigationLocation();
}
}
if (location != null) {
if (locationMemento != null) {
location.setInput(editorInfo.editorInput);
location.restoreState(locationMemento);
locationMemento = null;
}
location.restoreLocation();
}
} catch (PartInitException e) {
// ignore for now
}
}
}
/**
* Return the label to display in the history drop down list. Use the
* history entry text if the location has not been restored yet.
*/
String getHistoryText() {
if (location != null) {
// location exists or has been restored, use its text.
// Also update the historyText so that this value will
// be saved. Doing so handles cases where getText() value
// may be dynamic.
String text = location.getText();
if ((text == null) || text.equals("")) { //$NON-NLS-1$
text = historyText;
} else {
historyText = text;
}
return text;
} else {
return historyText;
}
}
/**
* Saves the state of this entry and its location.
* Returns true if possible otherwise returns false.
*/
boolean handlePartClosed() {
if (!editorInfo.isPersistable()) {
return false;
}
if (location != null) {
locationMemento = XMLMemento
.createWriteRoot(IWorkbenchConstants.TAG_POSITION);
location.saveState(locationMemento);
location.releaseState();
}
return true;
}
/**
* Saves the state of this entry and its location.
*/
void saveState(IMemento mem, ArrayList entries) {
mem.putString(IWorkbenchConstants.TAG_HISTORY_LABEL, getHistoryText());
if (locationMemento != null) {
IMemento childMem = mem
.createChild(IWorkbenchConstants.TAG_POSITION);
childMem.putMemento(locationMemento);
} else if (location != null) {
IMemento childMem = mem
.createChild(IWorkbenchConstants.TAG_POSITION);
location.saveState(childMem);
}
}
/**
* Restore the state of this entry.
*/
void restoreState(IMemento mem) {
historyText = mem.getString(IWorkbenchConstants.TAG_HISTORY_LABEL);
locationMemento = mem.getChild(IWorkbenchConstants.TAG_POSITION);
}
/*
* (non-Javadoc)
* Method declared on Object.
*/
public String toString() {
return "Input<" + editorInfo.editorInput + "> Details<" + location + ">"; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
}
/**
* Disposes this entry and its location.
*/
void dispose() {
if (location != null) {
location.dispose();
}
editorInfo = null;
}
/**
* Merges this entry into the current entry. Returns true
* if the merge was possible otherwise returns false.
*/
boolean mergeInto(NavigationHistoryEntry currentEntry) {
if (editorInfo.editorInput != null
&& editorInfo.editorInput
.equals(currentEntry.editorInfo.editorInput)) {
if (location != null) {
if (currentEntry.location == null) {
currentEntry.location = location;
return true;
} else {
return location.mergeInto(currentEntry.location);
}
} else if (currentEntry.location == null) {
return true;
}
}
return false;
}
}