Copyright (c) 2005, 2015 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2005, 2015 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.core.internal.filesystem;

import java.io.*;
import java.net.URI;
import java.net.URISyntaxException;
import org.eclipse.core.filesystem.*;
import org.eclipse.core.filesystem.provider.FileInfo;
import org.eclipse.core.filesystem.provider.FileStore;
import org.eclipse.core.runtime.*;

A null file store represents a file whose location is unknown,
such as a location based on an undefined variable.  This store
acts much like /dev/null on *nix: writes are ignored, reads return
empty streams, and modifications such as delete, mkdir, will fail.
/**
 * A null file store represents a file whose location is unknown,
 * such as a location based on an undefined variable.  This store
 * acts much like /dev/null on *nix: writes are ignored, reads return
 * empty streams, and modifications such as delete, mkdir, will fail.
 */
public class NullFileStore extends FileStore {
	private IPath path;

	
Creates a null file store
Params:
path – The path of the file in this store/**
	 * Creates a null file store
	 * @param path The path of the file in this store
	 */
	public NullFileStore(IPath path) {
		Assert.isNotNull(path);
		this.path = path;
	}

	@Override
	public IFileInfo[] childInfos(int options, IProgressMonitor monitor) {
		return EMPTY_FILE_INFO_ARRAY;
	}

	@Override
	public String[] childNames(int options, IProgressMonitor monitor) {
		return EMPTY_STRING_ARRAY;
	}

	@Override
	public void delete(int options, IProgressMonitor monitor) throws CoreException {
		//super implementation will always fail
		super.delete(options, monitor);
	}

	@Override
	public IFileInfo fetchInfo(int options, IProgressMonitor monitor) {
		FileInfo result = new FileInfo(getName());
		result.setExists(false);
		return result;
	}

	@Override
	public IFileStore getChild(String name) {
		return new NullFileStore(path.append(name));
	}

	@Override
	public IFileSystem getFileSystem() {
		return NullFileSystem.getInstance();
	}

	@Override
	public String getName() {
		return String.valueOf(path.lastSegment());
	}

	@Override
	public IFileStore getParent() {
		return path.segmentCount() == 0 ? null : new NullFileStore(path.removeLastSegments(1));
	}

	@Override
	public IFileStore mkdir(int options, IProgressMonitor monitor) throws CoreException {
		//super implementation will always fail
		return super.mkdir(options, monitor);
	}

	@Override
	public InputStream openInputStream(int options, IProgressMonitor monitor) {
		return new ByteArrayInputStream(new byte[0]);
	}

	@Override
	public OutputStream openOutputStream(int options, IProgressMonitor monitor) {
		return new OutputStream() {
			@Override
			public void write(int b) {
				//do nothing
			}
		};
	}

	@Override
	public void putInfo(IFileInfo info, int options, IProgressMonitor monitor) throws CoreException {
		//super implementation will always fail
		super.putInfo(info, options, monitor);
	}

	@Override
	public String toString() {
		return path.toString();
	}

	@Override
	public URI toURI() {
		try {
			return new URI(EFS.SCHEME_NULL, null, path.isEmpty() ? "/" : path.toString(), null); //$NON-NLS-1$
		} catch (URISyntaxException e) {
			//should never happen
			Policy.log(IStatus.ERROR, "Invalid URI", e); //$NON-NLS-1$
			return null;
		}
	}
}