XStreamMapColConverter.java

/**
 * This file is part of PaxmlCore.
 *
 * PaxmlCore is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * PaxmlCore 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with PaxmlCore.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.paxml.util;

import java.util.Collection;
import java.util.Map;

import org.paxml.core.ObjectTree;
import org.paxml.core.PaxmlRuntimeException;

import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;

public class XStreamMapColConverter implements Converter {
	private final String rootCollectionName;

	public XStreamMapColConverter(String rootCollectionName) {
		this.rootCollectionName = rootCollectionName == null ? "_" : rootCollectionName;
	}

	public boolean canConvert(final Class clazz) {
		return Map.class.isAssignableFrom(clazz) || isCollection(clazz);
	}

	public void marshal(final Object value, final HierarchicalStreamWriter writer, final MarshallingContext context) {
		if (value instanceof Map) {
			marshal((Map) value, writer, context);
		} else if (value instanceof Collection) {
			marshal((Collection) value, writer, context, null);
		} else {
			throw new PaxmlRuntimeException("Should not reach here!");
		}

	}

	static boolean isCollection(Class clazz) {
		return Collection.class.isAssignableFrom(clazz);
	}

	private void marshal(Collection col, HierarchicalStreamWriter writer, MarshallingContext context, String tagName) {
		if (tagName == null) {
			tagName = XStreamBeanConverter.getCurrentPropertyName(context);
			if (tagName == null) {
				tagName = rootCollectionName;
			}
		}
		for (Object v : col) {
			writer.startNode(tagName);
			context.convertAnother(v);
			writer.endNode();
		}
	}

	private void marshal(Map map, HierarchicalStreamWriter writer, MarshallingContext context) {
		if (map instanceof ObjectTree) {
			ObjectTree tree = (ObjectTree) map;
			for (Map.Entry<Object, Object> entry : ((Map<Object, Object>) map).entrySet()) {
				Object v = entry.getValue();
				String key = String.valueOf(entry.getKey());
				if (tree.isXmlAttribute(key)) {
					if (v != null) {
						writer.addAttribute(key, v.toString());
					}
				} else if (v instanceof Map) {
					writer.startNode(key);
					context.convertAnother(v);
					writer.endNode();
				} else if (v instanceof Collection) {
					marshal((Collection) v, writer, context, key);
				} else {
					writer.startNode(key);
					// writer.setValue(entry.getValue().toString());
					context.convertAnother(v);
					writer.endNode();

				}
			}
		} else {
			for (Map.Entry<Object, Object> entry : ((Map<Object, Object>) map).entrySet()) {
				Object v = entry.getValue();
				String key = String.valueOf(entry.getKey());
				if (v instanceof Map) {
					writer.startNode(key);
					context.convertAnother(v);
					writer.endNode();
				} else if (v instanceof Collection) {
					marshal((Collection) v, writer, context, key);
				} else {
					writer.startNode(key);
					// writer.setValue(entry.getValue().toString());
					context.convertAnother(v);
					writer.endNode();

				}
			}
		}
	}

	public Object unmarshal(final HierarchicalStreamReader reader, final UnmarshallingContext context) {
		throw new PaxmlRuntimeException("Use paxml parser instead!");
	}
}