Keyシリアライザ

Enumに続いて、com.google.appengine.api.datastore.Keyのシリアライザも実装。

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.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.KeyFactory;

/**
 * Keyのシリアライザ
 */
public class KeySerializer extends AbstractSerializer {


    /** UID */
    private static final long serialVersionUID = 4989497558259776800L;
    @Override @SuppressWarnings("unchecked")
    public boolean canSerialize(Class clazz, Class jsonClazz) {
        return Key.class == clazz && (jsonClazz == null || jsonClazz == JSONObject.class);
    }
    
    @Override @SuppressWarnings("unchecked") 
    public Class[] getJSONClasses() {
        return new Class[] {Key.class};
    }

    @Override @SuppressWarnings("unchecked") 
    public Class[] getSerializableClasses() {
        return new Class[] {};
    }

    @Override public Object marshall(SerializerState state, Object p, Object o)
    throws MarshallException {
        if (o instanceof Key) {
            return marshall( (Key) o );
        } else {
            throw new MarshallException("cannot marshall using class " + o.getClass());
        }
    }
    JSONObject marshall( Key k )
    throws MarshallException {
        JSONObject obj = new JSONObject();
        try {
            obj.put("javaClass", Key.class.getName());
            if ( k.getName() != null ) { 
                obj.put("name", k.getName());
            } else {
                obj.put("id", k.getId());
            }
            obj.put("kind", k.getKind());
            if ( k.getParent() != null ) obj.put("parent", marshall( k.getParent() ));
        } catch (JSONException e) {
            throw new MarshallException(e.getMessage(), e);
        }
        return obj;
    }
    @Override @SuppressWarnings("unchecked")
    public ObjectMatch tryUnmarshall( SerializerState state, Class clazz, Object o)
    throws UnmarshallException {
        JSONObject jso = (JSONObject) o;
        try {
            Class<?> cl = Class.forName(jso.getString("javaClass"));
            if ( cl != Key.class ) {
                throw new UnmarshallException("not a key.");
            }
            if ( !jso.has("kind") ) throw new UnmarshallException("not a key.");
            if ( !jso.has("name")  && !jso.has("id") ) {
                throw new UnmarshallException("not a key.");
            }
            state.setSerialized(o, ObjectMatch.OKAY);
            return ObjectMatch.OKAY;   
        } catch (Exception e) {
            throw new UnmarshallException("not a key.", e);
        }
    }

    @Override  @SuppressWarnings("unchecked")
    public Object unmarshall(SerializerState state, Class clazz, Object o)
    throws UnmarshallException {
        JSONObject jso = (JSONObject) o;
        try {
            Object returnValue = unmarshall( jso );
            state.setSerialized(o, returnValue);
            return returnValue;
        } catch (Exception e) {
            throw new UnmarshallException("not enum", e);
        }
    }
    Key unmarshall( JSONObject jso )
    throws MarshallException {
        try {
            String kind = jso.getString("kind");
            Key parent =  jso.has("parent") ? unmarshall( jso.getJSONObject("parent")) : null;
            if ( jso.has("name") ) {
                if ( parent != null ) {
                    return KeyFactory.createKey( parent, kind, jso.getString("name"));
                } else {
                    return KeyFactory.createKey( kind, jso.getString("name"));
                }
            } else {
                if ( parent != null ) {
                    return KeyFactory.createKey( parent, kind, jso.getLong("id"));
                } else {
                    return KeyFactory.createKey( kind, jso.getLong("id"));
                }
            }
        } catch (JSONException e) {
            throw new MarshallException(e.getMessage(), e);
        }
    }
}

有効化は例によって、JSONRPCBridgeにインスタンスを設定してやればOKです。

JSONRPCBridge bridge = JSONRPCBridge.getGlobalBridge();
bridge.registerSerializer( new KeySerializer() );