SyncInfoWriter.java

/*******************************************************************************
 * Copyright (c) 2000, 2005 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.core.internal.resources;

import java.io.DataOutputStream;
import java.io.IOException;
import java.util.*;
import org.eclipse.core.internal.watson.IPathRequestor;
import org.eclipse.core.runtime.QualifiedName;

public class SyncInfoWriter {
	protected Synchronizer synchronizer;

	protected Workspace workspace;

	// version number
	public static final int SYNCINFO_SAVE_VERSION= 3;

	public static final int SYNCINFO_SNAP_VERSION= 3;

	// for sync info
	public static final byte INDEX= 1;

	public static final byte QNAME= 2;

	public SyncInfoWriter(Workspace workspace, Synchronizer synchronizer) {
		super();
		this.workspace= workspace;
		this.synchronizer= synchronizer;
	}

	public void savePartners(DataOutputStream output) throws IOException {
		Set registry= synchronizer.getRegistry();
		output.writeInt(registry.size());
		for (Iterator i= registry.iterator(); i.hasNext();) {
			QualifiedName qname= (QualifiedName)i.next();
			output.writeUTF(qname.getQualifier());
			output.writeUTF(qname.getLocalName());
		}
	}

	/**
	 * SAVE_FILE -> VERSION_ID RESOURCE+ VERSION_ID -> int RESOURCE -> RESOURCE_PATH SIZE SYNCINFO*
	 * RESOURCE_PATH -> String SIZE -> int SYNCINFO -> TYPE BYTES TYPE -> INDEX | QNAME INDEX ->
	 * byte int QNAME -> byte String BYTES -> byte[]
	 */
	public void saveSyncInfo(ResourceInfo info, IPathRequestor requestor, DataOutputStream output, List writtenPartners) throws IOException {
		Map table= info.getSyncInfo(false);
		if (table == null)
			return;
		// if this is the first sync info that we have written, then
		// write the version id for the file.
		if (output.size() == 0)
			output.writeInt(SYNCINFO_SAVE_VERSION);
		output.writeUTF(requestor.requestPath().toString());
		output.writeInt(table.size());
		for (Iterator i= table.entrySet().iterator(); i.hasNext();) {
			Map.Entry entry= (Map.Entry)i.next();
			QualifiedName name= (QualifiedName)entry.getKey();
			// if we have already written the partner name once, then write an integer
			// constant to represent it instead to remove duplication
			int index= writtenPartners.indexOf(name);
			if (index == -1) {
				// FIXME: what to do about null qualifier?
				output.writeByte(QNAME);
				output.writeUTF(name.getQualifier());
				output.writeUTF(name.getLocalName());
				writtenPartners.add(name);
			} else {
				output.writeByte(INDEX);
				output.writeInt(index);
			}
			byte[] bytes= (byte[])entry.getValue();
			output.writeInt(bytes.length);
			output.write(bytes);
		}
	}

	/**
	 * SNAP_FILE -> [VERSION_ID RESOURCE]* VERSION_ID -> int RESOURCE -> RESOURCE_PATH SIZE
	 * SYNCINFO* RESOURCE_PATH -> String SIZE -> int SYNCINFO -> QNAME BYTES QNAME -> String String
	 * BYTES -> byte[]
	 */
	public void snapSyncInfo(ResourceInfo info, IPathRequestor requestor, DataOutputStream output) throws IOException {
		if (!info.isSet(ICoreConstants.M_SYNCINFO_SNAP_DIRTY))
			return;
		Map table= info.getSyncInfo(false);
		if (table == null)
			return;
		// write the version id for the snapshot.
		output.writeInt(SYNCINFO_SNAP_VERSION);
		output.writeUTF(requestor.requestPath().toString());
		output.writeInt(table.size());
		for (Iterator i= table.entrySet().iterator(); i.hasNext();) {
			Map.Entry entry= (Map.Entry)i.next();
			QualifiedName name= (QualifiedName)entry.getKey();
			output.writeUTF(name.getQualifier());
			output.writeUTF(name.getLocalName());
			byte[] bytes= (byte[])entry.getValue();
			output.writeInt(bytes.length);
			output.write(bytes);
		}
		info.clear(ICoreConstants.M_SYNCINFO_SNAP_DIRTY);
	}
}