org.eclipse.ogee.client/src/org/eclipse/ogee/client/parser/ODataJSONParser.java - gerrit/ogee/org.eclipse.ogee - Git at Google

 /*******************************************************************************
  *  Copyright (c) 2012-2014 SAP SE.
  *  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:
  *  SAP SE - initial API and implementation and/or initial documentation
  *
  *******************************************************************************/
 package org.eclipse.ogee.client.parser;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.logging.Logger;

 import org.eclipse.ogee.client.exceptions.MarshalerException;
 import org.eclipse.ogee.client.exceptions.ParserException;
 import org.eclipse.ogee.client.jsonsimple.JSONArray;
 import org.eclipse.ogee.client.jsonsimple.JSONObject;
 import org.eclipse.ogee.client.jsonsimple.JSONValue;
 import org.eclipse.ogee.client.jsonsimple.parser.JSONParser;
 import org.eclipse.ogee.client.jsonsimple.parser.ParseException;
 import org.eclipse.ogee.client.model.edmx.Edmx;
 import org.eclipse.ogee.client.model.generic.ODataCollection;
 import org.eclipse.ogee.client.model.generic.ODataEntry;
 import org.eclipse.ogee.client.model.generic.ODataProperty;
 import org.eclipse.ogee.client.model.generic.ServiceDocument;
 import org.eclipse.ogee.client.model.json.ODataCollectionJson;
 import org.eclipse.ogee.client.model.json.ODataEntryJson;
 import org.eclipse.ogee.client.model.json.ODataJsonTags;
 import org.eclipse.ogee.client.model.json.ODataLinkJson;
 import org.eclipse.ogee.client.model.json.ODataPropertyJson;
 import org.eclipse.ogee.client.model.json.ServiceDocumentJson;
 import org.eclipse.ogee.client.nls.messages.Messages;
 import org.eclipse.ogee.client.parser.impl.Marshaller;
 import org.eclipse.ogee.client.parser.impl.TypeConverter;

 /**
  * JSON specific implementation of IODataParser
  */
 public class ODataJSONParser implements IODataParser {
 	private static final String ENTITY_SETS_KEY = "EntitySets"; //$NON-NLS-1$
 	private final static Logger LOGGER = Logger.getLogger(ODataJSONParser.class
 			.getName());
 	private TypeConverter typeConverter = TypeConverter.JSON;

 	/**
 	 * Constructor
 	 */
 	public ODataJSONParser() {
 		super();
 	}

 	@Override
 	public ODataEntry parseODataEntry(String data) throws ParserException {
 		JSONObject jsonObject = parseJSONObject(data);

 		jsonObject = stripDtag(jsonObject);
 		jsonObject = stripResultsTag(jsonObject);

 		ODataEntryJson entry = new ODataEntryJson();

 		// iterate over the properties
 		Set<?> propertySet = ((HashMap<?, ?>) jsonObject).entrySet();

 		for (Object property : propertySet) {
 			Object key = ((Map.Entry<?, ?>) property).getKey();
 			Object value = ((Map.Entry<?, ?>) property).getValue();
 			populateODataEntry(entry, key, value);
 		}
 		return entry;
 	}

 	/**
 	 * @param jsonObject
 	 * @return - the given JSON object without the 'results' tag.
 	 */
 	private JSONObject stripResultsTag(JSONObject jsonObject) {
 		JSONObject dObject = (JSONObject) jsonObject
 				.get(ODataJsonTags.RESULTS_TAG);
 		if (dObject != null) {
 			return dObject;
 		}
 		return jsonObject;
 	}

 	/**
 	 * @param jsonObject
 	 * @return - the given JSON array without the 'results' tag.
 	 */
 	private JSONArray stripResultsTagFromJSONArray(JSONObject jsonObject) {
 		JSONArray jsonArray = (JSONArray) jsonObject
 				.get(ODataJsonTags.RESULTS_TAG);
 		if (jsonArray != null) {
 			return jsonArray;
 		}
 		return null;
 	}

 	/**
 	 * @param jsonObject
 	 * @return - the given JSON object without the 'd' tag.
 	 */
 	private JSONObject stripDtag(JSONObject jsonObject) {
 		JSONObject dObject = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);
 		if (dObject != null) {
 			return dObject;
 		}
 		return jsonObject;
 	}

 	/**
 	 * Populates OData JSON Entry with the given key and value.
 	 *
 	 * @param entry
 	 * @param key
 	 * @param value
 	 * @throws ParserException
 	 */
 	private void populateODataEntry(ODataEntryJson entry, Object key,
 			Object value) throws ParserException {
 		if (value == null) {
 			entry.putProperty(key.toString(), null);
 			return;
 		}
 		// check if this property is the metadata tag
 		if (key.equals(ODataJsonTags.METADATA_TAG)) {
 			HashMap<String, String> parsedMetadata = parseMetaData((HashMap<?, ?>) value);
 			entry.setMetadata(parsedMetadata);
 			entry.setId(parsedMetadata.get(ODataJsonTags.URI_TAG));
 			entry.setType(parsedMetadata.get(ODataJsonTags.TYPE_TAG));
 		}
 		// check if this property is the navigation property
 		else if (isLink(value)) {
 			ODataLinkJson link = parseLink(key, value);
 			entry.addLink(link);
 		} else {

 			// check if value is complex
 			if (isComplexProperty(value)) {
 				ODataPropertyJson parsedODataPropertyJson = (ODataPropertyJson) this
 						.parseODataProperty(value.toString());
 				parsedODataPropertyJson.setName(key.toString());
 				entry.putProperty(parsedODataPropertyJson);
 			} else if (isCollectionProperty(value)) {
 				ODataPropertyJson parsedODataPropertyJson = (ODataPropertyJson) this
 						.parseODataProperty(value.toString());

 				// Expanded Navigation Property with skipTonken.
 				if (parsedODataPropertyJson.getValue() == null) {
 					parsedODataPropertyJson = parsedODataPropertyJson
 							.getChildDataValue(ODataJsonTags.RESULTS_TAG);
 				}

 				ODataCollectionJson dataCollectionJson = (ODataCollectionJson) this
 						.parseODataCollection(parsedODataPropertyJson
 								.getValue());
 				parsedODataPropertyJson.setCollectionValue(dataCollectionJson);
 				parsedODataPropertyJson.setName(key.toString());
 				entry.putProperty(parsedODataPropertyJson);
 			} else {
 				// handle as simple property
 				entry.putProperty(key.toString(), value.toString());
 			}
 		}
 	}

 	/**
 	 * @param value
 	 * @return - true whether the given value is a complex property, and false
 	 *         otherwise.
 	 */
 	private boolean isComplexProperty(Object value) {
 		return (value.toString().startsWith("{") && !value.toString().startsWith("{\"results\"")); //$NON-NLS-1$ //$NON-NLS-2$
 	}

 	/**
 	 * @param value
 	 * @return - true whether the given value is a collection property, and
 	 *         false otherwise.
 	 */
 	private boolean isCollectionProperty(Object value) {
 		return value.toString().startsWith("{\"results\""); //$NON-NLS-1$
 	}

 	/**
 	 * Parses a link object given its key and value.
 	 *
 	 * @param key
 	 * @param value
 	 * @return
 	 */
 	private ODataLinkJson parseLink(Object key, Object value) {
 		Object defered = ((HashMap<?, ?>) value)
 				.get(ODataJsonTags.DEFERRED_TAG);
 		Object uri = ((HashMap<?, ?>) defered).get(ODataJsonTags.URI_TAG);
 		ODataLinkJson link = new ODataLinkJson();
 		link.setUri(uri.toString());
 		link.setTitle(key.toString());

 		return link;
 	}

 	/**
 	 * @param value
 	 * @return - true whether the given value is a link, and false otherwise.
 	 */
 	private boolean isLink(Object value) {
 		if (value instanceof Map) {
 			if ((((HashMap<?, ?>) value).get(ODataJsonTags.DEFERRED_TAG)) != null) {
 				return true;
 			} else {
 				return false;
 			}
 		} else {
 			return false;
 		}
 	}

 	/**
 	 * Parses the given metadata.
 	 *
 	 * @param metadata
 	 * @return
 	 */
 	private HashMap<String, String> parseMetaData(Map<?, ?> metadata) {
 		HashMap<String, String> parsedMetadata = new HashMap<String, String>();
 		for (Map.Entry<?, ?> entry : metadata.entrySet()) {
 			parsedMetadata.put(entry.getKey().toString(), entry.getValue()
 					.toString());
 		}

 		return parsedMetadata;
 	}

 	@SuppressWarnings("unchecked")
 	@Override
 	public ODataCollection parseODataCollection(String data)
 			throws ParserException {
 		LinkedList<ODataEntry> collection = new LinkedList<ODataEntry>();

 		JSONObject jsonObject = parseJSONObject(data);

 		jsonObject = stripDtag(jsonObject);
 		JSONArray jsonArray = stripResultsTagFromJSONArray(jsonObject);

 		if (jsonArray == null) {
 			return null;
 		}

 		for (Iterator<JSONObject> iterator = jsonArray.iterator(); iterator
 				.hasNext();) {
 			JSONObject jsonEntry = iterator.next();
 			ODataEntry parsedODataEntry = this.parseODataEntry(jsonEntry
 					.toJSONString());
 			collection.add(parsedODataEntry);
 		}

 		return convertToODataCollectionJson(collection);
 	}

 	/**
 	 * Parses a JSON object.
 	 *
 	 * @param data
 	 * @return
 	 * @throws ParserException
 	 */
 	private JSONObject parseJSONObject(String data) throws ParserException {
 		JSONParser jsonParser = new JSONParser();

 		Object obj;
 		try {
 			obj = jsonParser.parse(data);
 		} catch (ParseException e) {
 			String message = Messages.getString("ODataJSONParser.1"); //$NON-NLS-1$
 			LOGGER.warning(message);
 			throw new ParserException(message, e);
 		}

 		JSONObject jsonObject = (JSONObject) obj;
 		return jsonObject;
 	}

 	/**
 	 * Converts the given collection to an ODataCollectionJson object.
 	 *
 	 * @param collection
 	 * @return - the converted object.
 	 */
 	private ODataCollection convertToODataCollectionJson(
 			LinkedList<ODataEntry> collection) {
 		ODataCollectionJson odataCollection = new ODataCollectionJson();
 		ODataEntryJson[] entries = new ODataEntryJson[collection.size()];
 		odataCollection.setEntries(collection.toArray(entries));
 		return odataCollection;
 	}

 	@Override
 	public ODataProperty parseODataProperty(String data) throws ParserException {
 		ODataPropertyJson dataProperty = new ODataPropertyJson();
 		JSONObject jsonObject = parseJSONObject(data);

 		JSONObject obj2 = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);

 		if (obj2 != null) {
 			Map<?, ?> results = (HashMap<?, ?>) obj2
 					.get(ODataJsonTags.RESULTS_TAG);
 			if (results != null) {
 				return parseProperty(dataProperty, results);
 			} else {
 				Set<?> keySet = obj2.keySet();
 				if (keySet.size() == 1) {
 					Object object = obj2.get(keySet.iterator().next());
 					return parseProperty(dataProperty, (Map<?, ?>) object);
 				} else {
 					return parseProperty(dataProperty, obj2);
 				}
 			}
 		} else {
 			return parseProperty(dataProperty, jsonObject);
 		}
 	}

 	/**
 	 * Parses a property.
 	 *
 	 * @param property
 	 * @param properties
 	 * @return
 	 */
 	@SuppressWarnings("unchecked")
 	private ODataProperty parseProperty(ODataPropertyJson property,
 			Map<?, ?> properties) {
 		Set<String> keySet = (Set<String>) properties.keySet();

 		if (keySet.size() == 1) {
 			String key = keySet.iterator().next();
 			Object value = properties.get(key);
 			return primitivePropertyInitialization(property, key, value);
 		}

 		for (String key : keySet) {
 			Object value = properties.get(key);
 			if (key.equalsIgnoreCase(ODataJsonTags.METADATA_TAG)) {
 				addMetadata(property, properties);
 			} else {
 				addChildProperty(property, key, value);
 			}
 		}
 		return property;
 	}

 	/**
 	 * Add child property to the given property initialized with the given key
 	 * and value.
 	 *
 	 * @param dataProperty
 	 * @param key
 	 * @param value
 	 */
 	private void addChildProperty(ODataPropertyJson dataProperty, String key,
 			Object value) {
 		ODataPropertyJson childDataProperty = new ODataPropertyJson();
 		childDataProperty.setName(key);
 		childDataProperty.setValue(value.toString());
 		dataProperty.putChildProperty(childDataProperty);
 	}

 	/**
 	 * Add metadata to the given property.
 	 *
 	 * @param dataProperty
 	 * @param properties
 	 */
 	private void addMetadata(ODataPropertyJson dataProperty,
 			Map<?, ?> properties) {
 		JSONObject metadata = (JSONObject) properties
 				.get(ODataJsonTags.METADATA_TAG);
 		dataProperty.setMetadataType(metadata.get(ODataJsonTags.TYPE_TAG)
 				.toString());
 		dataProperty.setName(metadata.get(ODataJsonTags.TYPE_TAG).toString());
 	}

 	/**
 	 * Initializes the given property with the given key and value.
 	 *
 	 * @param dataProperty
 	 * @param key
 	 * @param value
 	 * @return - the property initialized.
 	 */
 	private ODataProperty primitivePropertyInitialization(
 			ODataPropertyJson dataProperty, String key, Object value) {
 		dataProperty.setName(key);
 		dataProperty.setValue(value.toString());
 		return dataProperty;
 	}

 	@SuppressWarnings("unchecked")
 	@Override
 	public ServiceDocument parseServiceDocument(String data)
 			throws ParserException {
 		JSONObject jsonObject = parseJSONObject(data);

 		// The name of the name/value pair is always "d" and the value is the
 		// JSON representation of an OData resource.
 		JSONObject obj2 = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);

 		// Service Documents are represented in JSON by an object with a single
 		// name/value pair with the name equal to "EntitySets" and the value
 		// being an array of Collection names.
 		List<String> entitySets = (ArrayList<String>) obj2.get(ENTITY_SETS_KEY);

 		// Initializing the ServiceDocument
 		ServiceDocument document = new ServiceDocumentJson();
 		String[] entitySetsArray = new String[entitySets.size()];
 		document.setCollections(entitySets.toArray(entitySetsArray));

 		return document;
 	}

 	@Override
 	public String format(ODataEntry entry) throws MarshalerException {
 		// using our implementation of 'toJSONString()' method
 		String jsonText = ((ODataEntryJson) entry).toJSONString();

 		return jsonText;
 	}

 	@SuppressWarnings({ "rawtypes", "unchecked" })
 	@Override
 	public String format(ODataCollection collection) throws MarshalerException {
 		// using LinkedHashMap so it will keep the order
 		Map root = new LinkedHashMap();
 		// representing the results as a JSON array (java.util.List)
 		JSONArray results = new JSONArray();

 		ODataEntry[] entries = collection.getEntries();
 		// going over all the entries and adding them to the 'results'
 		for (ODataEntry oDataEntry : entries) {
 			results.add(oDataEntry);
 		}

 		// adding the results to 'd'
 		root.put(ODataJsonTags.RESULTS_TAG, results);

 		// convert the json object to a string
 		// each child object calls its 'toJSONString' method
 		String jsonText = JSONValue.toJSONString(root);

 		return jsonText;
 	}

 	@Override
 	public TypeConverter getTypeConverter() {
 		return typeConverter;
 	}

 	@Override
 	public Representation getRepresentation() {
 		return Representation.JSON;
 	}

 	@Override
 	public String format(Edmx edmx) throws MarshalerException {
 		return Marshaller.getInstance().format(edmx);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2012-2014 SAP SE.
	* 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:
	* SAP SE - initial API and implementation and/or initial documentation
	*
	*******************************************************************************/
	package org.eclipse.ogee.client.parser;

	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.LinkedHashMap;
	import java.util.LinkedList;
	import java.util.List;
	import java.util.Map;
	import java.util.Set;
	import java.util.logging.Logger;

	import org.eclipse.ogee.client.exceptions.MarshalerException;
	import org.eclipse.ogee.client.exceptions.ParserException;
	import org.eclipse.ogee.client.jsonsimple.JSONArray;
	import org.eclipse.ogee.client.jsonsimple.JSONObject;
	import org.eclipse.ogee.client.jsonsimple.JSONValue;
	import org.eclipse.ogee.client.jsonsimple.parser.JSONParser;
	import org.eclipse.ogee.client.jsonsimple.parser.ParseException;
	import org.eclipse.ogee.client.model.edmx.Edmx;
	import org.eclipse.ogee.client.model.generic.ODataCollection;
	import org.eclipse.ogee.client.model.generic.ODataEntry;
	import org.eclipse.ogee.client.model.generic.ODataProperty;
	import org.eclipse.ogee.client.model.generic.ServiceDocument;
	import org.eclipse.ogee.client.model.json.ODataCollectionJson;
	import org.eclipse.ogee.client.model.json.ODataEntryJson;
	import org.eclipse.ogee.client.model.json.ODataJsonTags;
	import org.eclipse.ogee.client.model.json.ODataLinkJson;
	import org.eclipse.ogee.client.model.json.ODataPropertyJson;
	import org.eclipse.ogee.client.model.json.ServiceDocumentJson;
	import org.eclipse.ogee.client.nls.messages.Messages;
	import org.eclipse.ogee.client.parser.impl.Marshaller;
	import org.eclipse.ogee.client.parser.impl.TypeConverter;

	/**
	* JSON specific implementation of IODataParser
	*/
	public class ODataJSONParser implements IODataParser {
	private static final String ENTITY_SETS_KEY = "EntitySets"; //$NON-NLS-1$
	private final static Logger LOGGER = Logger.getLogger(ODataJSONParser.class
	.getName());
	private TypeConverter typeConverter = TypeConverter.JSON;

	/**
	* Constructor
	*/
	public ODataJSONParser() {
	super();
	}

	@Override
	public ODataEntry parseODataEntry(String data) throws ParserException {
	JSONObject jsonObject = parseJSONObject(data);

	jsonObject = stripDtag(jsonObject);
	jsonObject = stripResultsTag(jsonObject);

	ODataEntryJson entry = new ODataEntryJson();

	// iterate over the properties
	Set<?> propertySet = ((HashMap<?, ?>) jsonObject).entrySet();

	for (Object property : propertySet) {
	Object key = ((Map.Entry<?, ?>) property).getKey();
	Object value = ((Map.Entry<?, ?>) property).getValue();
	populateODataEntry(entry, key, value);
	}
	return entry;
	}

	/**
	* @param jsonObject
	* @return - the given JSON object without the 'results' tag.
	*/
	private JSONObject stripResultsTag(JSONObject jsonObject) {
	JSONObject dObject = (JSONObject) jsonObject
	.get(ODataJsonTags.RESULTS_TAG);
	if (dObject != null) {
	return dObject;
	}
	return jsonObject;
	}

	/**
	* @param jsonObject
	* @return - the given JSON array without the 'results' tag.
	*/
	private JSONArray stripResultsTagFromJSONArray(JSONObject jsonObject) {
	JSONArray jsonArray = (JSONArray) jsonObject
	.get(ODataJsonTags.RESULTS_TAG);
	if (jsonArray != null) {
	return jsonArray;
	}
	return null;
	}

	/**
	* @param jsonObject
	* @return - the given JSON object without the 'd' tag.
	*/
	private JSONObject stripDtag(JSONObject jsonObject) {
	JSONObject dObject = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);
	if (dObject != null) {
	return dObject;
	}
	return jsonObject;
	}

	/**
	* Populates OData JSON Entry with the given key and value.
	*
	* @param entry
	* @param key
	* @param value
	* @throws ParserException
	*/
	private void populateODataEntry(ODataEntryJson entry, Object key,
	Object value) throws ParserException {
	if (value == null) {
	entry.putProperty(key.toString(), null);
	return;
	}
	// check if this property is the metadata tag
	if (key.equals(ODataJsonTags.METADATA_TAG)) {
	HashMap<String, String> parsedMetadata = parseMetaData((HashMap<?, ?>) value);
	entry.setMetadata(parsedMetadata);
	entry.setId(parsedMetadata.get(ODataJsonTags.URI_TAG));
	entry.setType(parsedMetadata.get(ODataJsonTags.TYPE_TAG));
	}
	// check if this property is the navigation property
	else if (isLink(value)) {
	ODataLinkJson link = parseLink(key, value);
	entry.addLink(link);
	} else {

	// check if value is complex
	if (isComplexProperty(value)) {
	ODataPropertyJson parsedODataPropertyJson = (ODataPropertyJson) this
	.parseODataProperty(value.toString());
	parsedODataPropertyJson.setName(key.toString());
	entry.putProperty(parsedODataPropertyJson);
	} else if (isCollectionProperty(value)) {
	ODataPropertyJson parsedODataPropertyJson = (ODataPropertyJson) this
	.parseODataProperty(value.toString());

	// Expanded Navigation Property with skipTonken.
	if (parsedODataPropertyJson.getValue() == null) {
	parsedODataPropertyJson = parsedODataPropertyJson
	.getChildDataValue(ODataJsonTags.RESULTS_TAG);
	}

	ODataCollectionJson dataCollectionJson = (ODataCollectionJson) this
	.parseODataCollection(parsedODataPropertyJson
	.getValue());
	parsedODataPropertyJson.setCollectionValue(dataCollectionJson);
	parsedODataPropertyJson.setName(key.toString());
	entry.putProperty(parsedODataPropertyJson);
	} else {
	// handle as simple property
	entry.putProperty(key.toString(), value.toString());
	}
	}
	}

	/**
	* @param value
	* @return - true whether the given value is a complex property, and false
	* otherwise.
	*/
	private boolean isComplexProperty(Object value) {
	return (value.toString().startsWith("{") && !value.toString().startsWith("{\"results\"")); //$NON-NLS-1$ //$NON-NLS-2$
	}

	/**
	* @param value
	* @return - true whether the given value is a collection property, and
	* false otherwise.
	*/
	private boolean isCollectionProperty(Object value) {
	return value.toString().startsWith("{\"results\""); //$NON-NLS-1$
	}

	/**
	* Parses a link object given its key and value.
	*
	* @param key
	* @param value
	* @return
	*/
	private ODataLinkJson parseLink(Object key, Object value) {
	Object defered = ((HashMap<?, ?>) value)
	.get(ODataJsonTags.DEFERRED_TAG);
	Object uri = ((HashMap<?, ?>) defered).get(ODataJsonTags.URI_TAG);
	ODataLinkJson link = new ODataLinkJson();
	link.setUri(uri.toString());
	link.setTitle(key.toString());

	return link;
	}

	/**
	* @param value
	* @return - true whether the given value is a link, and false otherwise.
	*/
	private boolean isLink(Object value) {
	if (value instanceof Map) {
	if ((((HashMap<?, ?>) value).get(ODataJsonTags.DEFERRED_TAG)) != null) {
	return true;
	} else {
	return false;
	}
	} else {
	return false;
	}
	}

	/**
	* Parses the given metadata.
	*
	* @param metadata
	* @return
	*/
	private HashMap<String, String> parseMetaData(Map<?, ?> metadata) {
	HashMap<String, String> parsedMetadata = new HashMap<String, String>();
	for (Map.Entry<?, ?> entry : metadata.entrySet()) {
	parsedMetadata.put(entry.getKey().toString(), entry.getValue()
	.toString());
	}

	return parsedMetadata;
	}

	@SuppressWarnings("unchecked")
	@Override
	public ODataCollection parseODataCollection(String data)
	throws ParserException {
	LinkedList<ODataEntry> collection = new LinkedList<ODataEntry>();

	JSONObject jsonObject = parseJSONObject(data);

	jsonObject = stripDtag(jsonObject);
	JSONArray jsonArray = stripResultsTagFromJSONArray(jsonObject);

	if (jsonArray == null) {
	return null;
	}

	for (Iterator<JSONObject> iterator = jsonArray.iterator(); iterator
	.hasNext();) {
	JSONObject jsonEntry = iterator.next();
	ODataEntry parsedODataEntry = this.parseODataEntry(jsonEntry
	.toJSONString());
	collection.add(parsedODataEntry);
	}

	return convertToODataCollectionJson(collection);
	}

	/**
	* Parses a JSON object.
	*
	* @param data
	* @return
	* @throws ParserException
	*/
	private JSONObject parseJSONObject(String data) throws ParserException {
	JSONParser jsonParser = new JSONParser();

	Object obj;
	try {
	obj = jsonParser.parse(data);
	} catch (ParseException e) {
	String message = Messages.getString("ODataJSONParser.1"); //$NON-NLS-1$
	LOGGER.warning(message);
	throw new ParserException(message, e);
	}

	JSONObject jsonObject = (JSONObject) obj;
	return jsonObject;
	}

	/**
	* Converts the given collection to an ODataCollectionJson object.
	*
	* @param collection
	* @return - the converted object.
	*/
	private ODataCollection convertToODataCollectionJson(
	LinkedList<ODataEntry> collection) {
	ODataCollectionJson odataCollection = new ODataCollectionJson();
	ODataEntryJson[] entries = new ODataEntryJson[collection.size()];
	odataCollection.setEntries(collection.toArray(entries));
	return odataCollection;
	}

	@Override
	public ODataProperty parseODataProperty(String data) throws ParserException {
	ODataPropertyJson dataProperty = new ODataPropertyJson();
	JSONObject jsonObject = parseJSONObject(data);

	JSONObject obj2 = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);

	if (obj2 != null) {
	Map<?, ?> results = (HashMap<?, ?>) obj2
	.get(ODataJsonTags.RESULTS_TAG);
	if (results != null) {
	return parseProperty(dataProperty, results);
	} else {
	Set<?> keySet = obj2.keySet();
	if (keySet.size() == 1) {
	Object object = obj2.get(keySet.iterator().next());
	return parseProperty(dataProperty, (Map<?, ?>) object);
	} else {
	return parseProperty(dataProperty, obj2);
	}
	}
	} else {
	return parseProperty(dataProperty, jsonObject);
	}
	}

	/**
	* Parses a property.
	*
	* @param property
	* @param properties
	* @return
	*/
	@SuppressWarnings("unchecked")
	private ODataProperty parseProperty(ODataPropertyJson property,
	Map<?, ?> properties) {
	Set<String> keySet = (Set<String>) properties.keySet();

	if (keySet.size() == 1) {
	String key = keySet.iterator().next();
	Object value = properties.get(key);
	return primitivePropertyInitialization(property, key, value);
	}

	for (String key : keySet) {
	Object value = properties.get(key);
	if (key.equalsIgnoreCase(ODataJsonTags.METADATA_TAG)) {
	addMetadata(property, properties);
	} else {
	addChildProperty(property, key, value);
	}
	}
	return property;
	}

	/**
	* Add child property to the given property initialized with the given key
	* and value.
	*
	* @param dataProperty
	* @param key
	* @param value
	*/
	private void addChildProperty(ODataPropertyJson dataProperty, String key,
	Object value) {
	ODataPropertyJson childDataProperty = new ODataPropertyJson();
	childDataProperty.setName(key);
	childDataProperty.setValue(value.toString());
	dataProperty.putChildProperty(childDataProperty);
	}

	/**
	* Add metadata to the given property.
	*
	* @param dataProperty
	* @param properties
	*/
	private void addMetadata(ODataPropertyJson dataProperty,
	Map<?, ?> properties) {
	JSONObject metadata = (JSONObject) properties
	.get(ODataJsonTags.METADATA_TAG);
	dataProperty.setMetadataType(metadata.get(ODataJsonTags.TYPE_TAG)
	.toString());
	dataProperty.setName(metadata.get(ODataJsonTags.TYPE_TAG).toString());
	}

	/**
	* Initializes the given property with the given key and value.
	*
	* @param dataProperty
	* @param key
	* @param value
	* @return - the property initialized.
	*/
	private ODataProperty primitivePropertyInitialization(
	ODataPropertyJson dataProperty, String key, Object value) {
	dataProperty.setName(key);
	dataProperty.setValue(value.toString());
	return dataProperty;
	}

	@SuppressWarnings("unchecked")
	@Override
	public ServiceDocument parseServiceDocument(String data)
	throws ParserException {
	JSONObject jsonObject = parseJSONObject(data);

	// The name of the name/value pair is always "d" and the value is the
	// JSON representation of an OData resource.
	JSONObject obj2 = (JSONObject) jsonObject.get(ODataJsonTags.D_TAG);

	// Service Documents are represented in JSON by an object with a single
	// name/value pair with the name equal to "EntitySets" and the value
	// being an array of Collection names.
	List<String> entitySets = (ArrayList<String>) obj2.get(ENTITY_SETS_KEY);

	// Initializing the ServiceDocument
	ServiceDocument document = new ServiceDocumentJson();
	String[] entitySetsArray = new String[entitySets.size()];
	document.setCollections(entitySets.toArray(entitySetsArray));

	return document;
	}

	@Override
	public String format(ODataEntry entry) throws MarshalerException {
	// using our implementation of 'toJSONString()' method
	String jsonText = ((ODataEntryJson) entry).toJSONString();

	return jsonText;
	}

	@SuppressWarnings({ "rawtypes", "unchecked" })
	@Override
	public String format(ODataCollection collection) throws MarshalerException {
	// using LinkedHashMap so it will keep the order
	Map root = new LinkedHashMap();
	// representing the results as a JSON array (java.util.List)
	JSONArray results = new JSONArray();

	ODataEntry[] entries = collection.getEntries();
	// going over all the entries and adding them to the 'results'
	for (ODataEntry oDataEntry : entries) {
	results.add(oDataEntry);
	}

	// adding the results to 'd'
	root.put(ODataJsonTags.RESULTS_TAG, results);

	// convert the json object to a string
	// each child object calls its 'toJSONString' method
	String jsonText = JSONValue.toJSONString(root);

	return jsonText;
	}

	@Override
	public TypeConverter getTypeConverter() {
	return typeConverter;
	}

	@Override
	public Representation getRepresentation() {
	return Representation.JSON;
	}

	@Override
	public String format(Edmx edmx) throws MarshalerException {
	return Marshaller.getInstance().format(edmx);
	}
	}