/**
 * Copyright (C) 2010-2017 Structr GmbH
 *
 * This file is part of Structr <http://structr.org>.
 *
 * Structr is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * Structr is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Structr.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.structr.core.parser;

import org.structr.common.error.FrameworkException;
import org.structr.core.GraphObject;
import org.structr.schema.action.ActionContext;

/**
 *
 *
 */
public class NullExpression extends Expression {

	@Override
	public String toString() {

		final StringBuilder buf = new StringBuilder();

		buf.append("null");

		return buf.toString();
	}

	@Override
	public Object evaluate(final ActionContext ctx, final GraphObject entity) throws FrameworkException {
		return null;
	}

	@Override
	public Object transform(final ActionContext ctx, final GraphObject entity, final Object source) throws FrameworkException {
		return source;
	}
}