bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/dialogs/FileSystemElement.java

/*******************************************************************************
 * Copyright (c) 2000, 2003 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.eclipse.ui.dialogs;

import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.Platform;
import org.eclipse.ui.internal.*;
import org.eclipse.ui.internal.model.AdaptableList;
import org.eclipse.ui.internal.model.WorkbenchAdapter;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.model.IWorkbenchAdapter;
import org.eclipse.jface.resource.ImageDescriptor;

/**
 *  Instances of this class represent files or file-like entities (eg.- zip
 *  file entries) on the local file system.  They do not represent resources
 *  within the workbench.  This distinction is made because the representation of
 *  a file system resource is significantly different from that of a workbench
 *  resource.
 *
 *  If self represents a collection (eg.- file system directory, zip directory)
 *  then its icon will be the folderIcon static field.  Otherwise (ie.- self
 *  represents a file system file) self's icon is stored in field "icon", and is
 *  determined by the extension of the file that self represents.
 *
 * This class is adaptable, and implements one adapter itself, namely the 
 * IWorkbenchAdapter adapter used for navigation and display in the workbench.
 */
public class FileSystemElement implements IAdaptable {
	private String name;
	private Object fileSystemObject;

	/* Wait until a child is added to initialize the receiver's lists.
	 * Doing so minimizes the amount of memory that is allocated when
	 * a large directory structure is being processed.
	 */
	private AdaptableList folders = null;
	private AdaptableList files = null;

	private boolean isDirectory = false;
	private FileSystemElement parent;

	private final static AdaptableList EMPTY_LIST = new AdaptableList(0);

	private WorkbenchAdapter workbenchAdapter = new WorkbenchAdapter() {
		/**
		 *	Answer the children property of this element
		 */
		public Object[] getChildren(Object o) {
			return getFolders().getChildren(o);
		}
		/**
		 * Returns the parent of this element
		 */
		public Object getParent(Object o) {
			return parent;
		}
		/**
		 * Returns an appropriate label for this file system element.
		 */
		public String getLabel(Object o) {
			return name;
		}
	/**
	 * Returns an image descriptor for this file system element
	 */
	public ImageDescriptor getImageDescriptor(Object object) {
		if (isDirectory()) {
			return WorkbenchImages.getImageDescriptor(ISharedImages.IMG_OBJ_FOLDER);
		} else {
			return WorkbenchPlugin.getDefault().getEditorRegistry().getImageDescriptor(name);
		}
	}
};
/**
 * Creates a new <code>FileSystemElement</code> and initializes it
 * and its parent if applicable.
 *
 * @param name java.lang.String
 */
public FileSystemElement(String name,FileSystemElement parent,boolean isDirectory) {
	this.name = name;
	this.parent = parent;
	this.isDirectory = isDirectory;
	if (parent != null)
		parent.addChild(this);
}
/**
 * Adds the passed child to this object's collection of children.
 *
 * @param child FileSystemElement
 */
public void addChild(FileSystemElement child) {
	if (child.isDirectory()) {
		if (folders == null) folders = new AdaptableList(1);
		folders.add(child);
	} else {
		if (files == null) files = new AdaptableList(1);
		files.add(child);
	}
}
/**
 * Returns the adapter
 */
public Object getAdapter(Class adapter) {
	if (adapter == IWorkbenchAdapter.class) {
		return workbenchAdapter;
	}
	//defer to the platform
	return Platform.getAdapterManager().getAdapter(this, adapter);
}
/** 
 * Returns the extension of this element's filename.  Returns
 * The empty string if there is no extension.
 */
public String getFileNameExtension() {
	int lastDot = name.lastIndexOf('.');
	return lastDot < 0 ? "" : name.substring(lastDot+1);	//$NON-NLS-1$
}
/**
 *	Answer the files property of this element.  Answer an empty list if the
 *  files property is null. 
 *  This method should not be used to add children
 *  to the receiver. Use addChild(FileSystemElement) instead.
 */
public AdaptableList getFiles() {
	
	if (files == null) return EMPTY_LIST;
	return files;
}
/**
 *	Returns the file system object property of this element
 *
 *	@return the file system object
 */
public Object getFileSystemObject() {
	return fileSystemObject;
}
/**
 * Returns a list of the folders that are immediate children
 * of this folder.  Answer an empty list if the folders property is null.
 * This method should not be used to add children
 * to the receiver. Use addChild(FileSystemElement) instead.
 */
public AdaptableList getFolders() {
	if (folders == null) return EMPTY_LIST;
	return folders;
}
/**
 * Return the parent of this element.
 *
 * @return the parent file system element, or <code>null</code> if this is the root
 */
public FileSystemElement getParent() {
	return this.parent;
}
/**
 * Returns true if this element represents a directory, and false
 * otherwise.
 */
public boolean isDirectory() {
	return isDirectory;
}
/**
 * Removes a sub-folder from this file system element.
 */
public void removeFolder(FileSystemElement child) {
	if (folders == null) return;
	folders.remove(child);
	child.setParent(null);
}
/**
 *	Set the file system object property of this element
 *
 *	@param value the file system object
 */
public void setFileSystemObject(Object value) {
	fileSystemObject = value;
}
/**
 * Sets the parent of this file system element.
 */
public void setParent(FileSystemElement element) {
	parent = element;
}
/**
 * For debugging purposes only.
 */
public String toString() {
	StringBuffer buf = new StringBuffer();
	if (isDirectory()) {
		buf.append("Folder(");//$NON-NLS-1$
	} else {
		buf.append("File(");//$NON-NLS-1$
	}
	buf.append(name).append(")");//$NON-NLS-1$

	if (!isDirectory()) {
		return buf.toString();
	}

	buf.append(" folders: ");//$NON-NLS-1$
	buf.append(folders);
	buf.append(" files: ");//$NON-NLS-1$
	buf.append(files);
	return buf.toString();
}
}