OpenNxSerialization

/*
 * @(#)NxCollectionSerializationSurrogate.java	1.0
 *
 * Created on September 18, 2008, 12:59 PM
 *
 * Copyright 2008 NeXtreme Innovations, Inc. All rights reserved.
 * "NeXtreme Innovations" PROPRIETARY/CONFIDENTIAL. Use is subject
 * to license terms.
 */
package com.nextreme.opennxserialization.standard.io.surrogates;

import com.nextreme.opennxserialization.core.io.NxObjectInput;
import com.nextreme.opennxserialization.core.io.NxObjectOutput;
import com.nextreme.opennxserialization.core.io.surrogates.NxBuiltinSerializationSurrogate;
import com.nextreme.opennxserialization.core.io.surrogates.NxIOException;
import com.nextreme.opennxserialization.core.io.surrogates.NxInstantiationException;
import com.nextreme.opennxserialization.core.io.surrogates.NxSerializationSurrogateImpl;
import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;

/**
 * NxCollectionSerializationSurrogate<E> is responsible for writing and reading
 * instances of Collection<E> class.
 *
 * @version 1.0, September 18, 2008
 */
public abstract class NxCollectionSerializationSurrogate<E>
        extends NxSerializationSurrogateImpl
        implements NxBuiltinSerializationSurrogate
{
    /** Creates a new instance of NxBooleanSerializationSurrogate */
    public NxCollectionSerializationSurrogate(Class<? extends Collection<E>> cls) {
        super(cls);
    }
    
    /**
     * Read an object of type returned by getRealClass() from the stream reader.
     * A fresh instance of the object is passed as parameter.
     * The surrogate should populate fields in the object from data on the stream
     *
     * @param input stream reader
     * @param graph a fresh instance of the object that the surrogate must deserialize.
     * @exception NxInstantiationException Object creation related exceptions.
     * @exception NxIOException Any of the usual Input/Output related exceptions.
     * @return object read from the stream reader
     */
    public Object readDirect(NxObjectInput input, Object graph)
	throws NxInstantiationException, NxIOException
    {
        Collection<E> object = (Collection<E>)graph;
        try {
            int len = input.readInt();
            for (int i = 0; i < len; i++)
            {
                E item = (E) input.readObject();
                object.add(item);
            }
        } catch (ClassNotFoundException ex) {
            throw new NxIOException(ex);
        } catch (IOException ex) {
            throw new NxIOException(ex);
        }
        return graph;
    }

    /**
     * Write an object of type returned by getRealClass( to the stream writer
     *
     * @param output stream writer
     * @param graph object to be written to the stream reader
     * @exception NxIOException Any of the usual Input/Output related exceptions.
     */
    public void writeDirect(NxObjectOutput output, Object graph)
      throws NxIOException
   {
        Collection<E> object = (Collection<E>)graph;
        int len = object.size();
        
        try {
            output.writeInt(len);
            if(len > 0)
            {
                Iterator<E> iter = object.iterator();
                while(iter.hasNext())
                {
                    output.writeObject(iter.next());
                }
            }
        } catch (IOException ex) {
            throw new NxIOException(ex);
        }
    }
}