Copyright (c) 2000, 2016 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
    James Blackburn (Broadcom Corp.) - ongoing development
    Lars Vogel  - Bug 473427
    Mickael Istria (Red Hat Inc.) - Bug 488937
/*******************************************************************************
 * Copyright (c) 2000, 2016 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
 *     James Blackburn (Broadcom Corp.) - ongoing development
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 473427
 *     Mickael Istria (Red Hat Inc.) - Bug 488937
 *******************************************************************************/
package org.eclipse.core.internal.resources;

import java.io.*;
import java.util.*;
import org.eclipse.core.internal.utils.Messages;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.IResourceStatus;
import org.eclipse.core.runtime.*;

This class is used to read markers from disk. This is for version 1.
/**
 * This class is used to read markers from disk. This is for version 1.
 */
public class MarkerReader_1 extends MarkerReader {

	// type constants
	public static final int INDEX = 1;
	public static final int QNAME = 2;

	// marker attribute types
	public static final int ATTRIBUTE_NULL = -1;
	public static final int ATTRIBUTE_BOOLEAN = 0;
	public static final int ATTRIBUTE_INTEGER = 1;
	public static final int ATTRIBUTE_STRING = 2;

	public MarkerReader_1(Workspace workspace) {
		super(workspace);
	}

	
 
SAVE_FILE -> VERSION_ID RESOURCE+
VERSION_ID ->
RESOURCE -> RESOURCE_PATH MARKERS_SIZE MARKER*
RESOURCE_PATH -> String
MARKERS_SIZE -> int
MARKER -> MARKER_ID TYPE ATTRIBUTES_SIZE ATTRIBUTE*
MARKER_ID -> long
TYPE -> INDEX | QNAME
INDEX -> int int
QNAME -> int String
ATTRIBUTES_SIZE -> int
ATTRIBUTE -> ATTRIBUTE_KEY ATTRIBUTE_VALUE
ATTRIBUTE_KEY -> String
ATTRIBUTE_VALUE -> INTEGER_VALUE | BOOLEAN_VALUE | STRING_VALUE | NULL_VALUE
INTEGER_VALUE -> int int
BOOLEAN_VALUE -> int boolean
STRING_VALUE -> int String
NULL_VALUE -> int

/**
	 * <pre> {@code
	 * SAVE_FILE -> VERSION_ID RESOURCE+
	 * VERSION_ID ->
	 * RESOURCE -> RESOURCE_PATH MARKERS_SIZE MARKER*
	 * RESOURCE_PATH -> String
	 * MARKERS_SIZE -> int
	 * MARKER -> MARKER_ID TYPE ATTRIBUTES_SIZE ATTRIBUTE*
	 * MARKER_ID -> long
	 * TYPE -> INDEX | QNAME
	 * INDEX -> int int
	 * QNAME -> int String
	 * ATTRIBUTES_SIZE -> int
	 * ATTRIBUTE -> ATTRIBUTE_KEY ATTRIBUTE_VALUE
	 * ATTRIBUTE_KEY -> String
	 * ATTRIBUTE_VALUE -> INTEGER_VALUE | BOOLEAN_VALUE | STRING_VALUE | NULL_VALUE
	 * INTEGER_VALUE -> int int
	 * BOOLEAN_VALUE -> int boolean
	 * STRING_VALUE -> int String
	 * NULL_VALUE -> int
	 * }</pre>
	 */
	@Override
	public void read(DataInputStream input, boolean generateDeltas) throws IOException, CoreException {
		try {
			List<String> readTypes = new ArrayList<>(5);
			while (true) {
				IPath path = new Path(input.readUTF());
				int markersSize = input.readInt();
				MarkerSet markers = new MarkerSet(markersSize);
				for (int i = 0; i < markersSize; i++)
					markers.add(readMarkerInfo(input, readTypes));
				// if the resource doesn't exist then return. ensure we do this after
				// reading the markers from the file so we don't get into an
				// inconsistent state.
				ResourceInfo info = workspace.getResourceInfo(path, false, false);
				if (info == null)
					continue;
				info.setMarkers(markers);
				if (generateDeltas) {
					Resource resource = workspace.newResource(path, info.getType());
					// Iterate over all elements and add not null ones. This saves us from copying
					// and shrinking the array.
					IMarkerSetElement[] infos = markers.elements;
					ArrayList<MarkerDelta> deltas = new ArrayList<>(infos.length);
					for (IMarkerSetElement info2 : infos)
						if (info2 != null)
							deltas.add(new MarkerDelta(IResourceDelta.ADDED, resource, (MarkerInfo) info2));
					workspace.getMarkerManager().changedMarkers(resource, deltas.toArray(new IMarkerSetElement[deltas.size()]));
				}
			}
		} catch (EOFException e) {
			// ignore end of file
		}
	}

	private Map<String, Object> readAttributes(DataInputStream input) throws IOException {
		int attributesSize = input.readInt();
		if (attributesSize == 0)
			return null;
		Map<String, Object> result = new MarkerAttributeMap<>(attributesSize);
		for (int j = 0; j < attributesSize; j++) {
			String key = input.readUTF();
			int type = input.readInt();
			Object value = null;
			switch (type) {
				case ATTRIBUTE_INTEGER :
					value = input.readInt();
					break;
				case ATTRIBUTE_BOOLEAN :
					value = input.readBoolean();
					break;
				case ATTRIBUTE_STRING :
					value = input.readUTF();
					break;
				case ATTRIBUTE_NULL :
					// do nothing
					break;
			}
			if (value != null)
				result.put(key, value);
		}
		return result.isEmpty() ? null : result;
	}

	private MarkerInfo readMarkerInfo(DataInputStream input, List<String> readTypes) throws IOException, CoreException {
		MarkerInfo info = new MarkerInfo();
		info.setId(input.readLong());
		int constant = input.readInt();
		switch (constant) {
			case QNAME :
				String type = input.readUTF();
				info.setType(type);
				readTypes.add(type);
				break;
			case INDEX :
				info.setType(readTypes.get(input.readInt()));
				break;
			default :
				//if we get here the marker file is corrupt
				String msg = Messages.resources_readMarkers;
				throw new ResourceException(IResourceStatus.FAILED_READ_METADATA, null, msg, null);
		}
		info.internalSetAttributes(readAttributes(input));
		return info;
	}
}