src/org/tiefaces/components/websheet/serializable/SerialDataContext.java
private void writeObject(final java.io.ObjectOutputStream out)
			throws IOException {
		Gson objGson = new GsonBuilder().setPrettyPrinting().create();
		this.mapToJson = objGson.toJson(this.dataContext);
		out.defaultWriteObject();
	}
private void writeObject(final java.io.ObjectOutputStream out)
			throws IOException {
		Gson objGson = new GsonBuilder().setPrettyPrinting().create();
		this.mapToJson = objGson.toJson(this.dataContext);
		out.defaultWriteObject();
	}
save the workbook before serialize.

@param out
outputstream.
@throws IOException
io exception.