NSSetSerializer.java

package er.ajax.json.serializer;

import java.util.Enumeration;
import java.util.Iterator;

import org.jabsorb.serializer.AbstractSerializer;
import org.jabsorb.serializer.MarshallException;
import org.jabsorb.serializer.ObjectMatch;
import org.jabsorb.serializer.SerializerState;
import org.jabsorb.serializer.UnmarshallException;
import org.json.JSONException;
import org.json.JSONObject;

import com.webobjects.foundation.NSMutableSet;
import com.webobjects.foundation.NSSet;

/**
 * Transforms NSSets between JavaScript and Java.
 * 
 * @author Jean-François Veillette <jfveillette@os.ca>
 * @version $, $Date $ <br>
 *          © 2005 OS Communications Informatiques, inc. Tous droits réservés.
 */
class NSSetSerializer extends AbstractSerializer {
	/**
	 * Do I need to update serialVersionUID?
	 * See section 5.6 <cite>Type Changes Affecting Serialization</cite> on page 51 of the 
	 * <a href="http://java.sun.com/j2se/1.4/pdf/serial-spec.pdf">Java Object Serialization Spec</a>
	 */
	private static final long serialVersionUID = 1L;

	private static Class[] _serializableClasses = new Class[] { NSSet.class, NSMutableSet.class };
	private static Class[] _JSONClasses = new Class[] { JSONObject.class };

	public Class[] getSerializableClasses() {
		return _serializableClasses;
	}

	public Class[] getJSONClasses() {
		return _JSONClasses;
	}

	@Override
	public boolean canSerialize(Class clazz, Class jsonClazz) {
		return (super.canSerialize(clazz, jsonClazz) || ((jsonClazz == null || jsonClazz == JSONObject.class) && NSSet.class.isAssignableFrom(clazz)));
	}

	public ObjectMatch tryUnmarshall(SerializerState state, Class clazz, Object o) throws UnmarshallException {
		try {
			JSONObject jso = (JSONObject) o;
			String java_class = jso.getString("javaClass");
			if (java_class == null) {
				throw new UnmarshallException("no type hint");
			}
			if (!(java_class.equals("com.webobjects.foundation.NSSet") || java_class.equals("com.webobjects.foundation.NSMutableSet"))) {
				throw new UnmarshallException("not a Set");
			}
			JSONObject jsonset = jso.getJSONObject("set");
			if (jsonset == null) {
				throw new UnmarshallException("set missing");
			}

			ObjectMatch m = new ObjectMatch(-1);

			Iterator i = jsonset.keys();
			String key = null;

			try {
				while (i.hasNext()) {
					key = (String) i.next();
					m = ser.tryUnmarshall(state, null, jsonset.get(key)).max(m);
				}
			}
			catch (UnmarshallException e) {
				throw new UnmarshallException("key " + key + " " + e.getMessage());
			}
			return m;
		}
		catch (JSONException e) {
			throw new UnmarshallException("Failed to unmarshall NSSet.", e);
		}

	}

	public Object unmarshall(SerializerState state, Class clazz, Object o) throws UnmarshallException {
		try {
			JSONObject jso = (JSONObject) o;
			String java_class = jso.getString("javaClass");
			if (java_class == null) {
				throw new UnmarshallException("no type hint");
			}
			NSMutableSet abset = null;
			if (java_class.equals("com.webobjects.foundation.NSSet") || java_class.equals("com.webobjects.foundation.NSMutableSet")) {
				abset = new NSMutableSet();
			}
			else {
				throw new UnmarshallException("not a Set");
			}
			JSONObject jsonset = jso.getJSONObject("set");

			if (jsonset == null) {
				throw new UnmarshallException("set missing");
			}

			Iterator i = jsonset.keys();
			String key = null;

			try {
				while (i.hasNext()) {
					key = (String) i.next();
					Object setElement = jsonset.get(key);
					Object unmarshalledObject = ser.unmarshall(state, null, setElement);
					abset.addObject(unmarshalledObject);
				}
			}
			catch (UnmarshallException e) {
				throw new UnmarshallException("key " + i + e.getMessage());
			}
			return abset;
		}
		catch (JSONException e) {
			throw new UnmarshallException("Failed to unmarshall NSSet.", e);
		}
	}

	public Object marshall(SerializerState state, Object p, Object o) throws MarshallException {
		try {
			NSSet set = (NSSet) o;

			JSONObject obj = new JSONObject();
			JSONObject setdata = new JSONObject();
			obj.put("javaClass", o.getClass().getName());
			obj.put("set", setdata);
			String key = null;
			try {
				int index = 0;
				Enumeration i = set.objectEnumerator();
				while (i.hasMoreElements()) {
					Object value = i.nextElement();
					setdata.put(key, ser.marshall(state, o, value, Integer.valueOf(index)));
					index++;
				}
			}
			catch (MarshallException e) {
				throw new MarshallException("set key " + key + e.getMessage());
			}
			return obj;
		}
		catch (JSONException e) {
			throw new MarshallException("Failed to marshall NSSet.", e);
		}
	}
}