JoinTableConverter.java

/*
 * Copyright (c) 2017 OBiBa. All rights reserved.
 *
 * This program and the accompanying materials
 * are made available under the terms of the GNU Public License v3.0.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.obiba.magma.xstream.converter;

import java.util.ArrayList;
import java.util.List;

import org.obiba.magma.ValueTable;
import org.obiba.magma.support.ValueTableReference;
import org.obiba.magma.views.JoinTable;

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 JoinTableConverter implements Converter {

  public static final JoinTableConverter INSTANCE = new JoinTableConverter();

  @Override
  public boolean canConvert(@SuppressWarnings("rawtypes") Class type) {
    return JoinTable.class.isAssignableFrom(type);
  }

  @Override
  public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
    JoinTable joinTable = (JoinTable) source;

    writer.startNode("list");
    for(ValueTable vt : joinTable.getTables()) {
      if(vt instanceof ValueTableReference) {
        writer.startNode("table");
        writer.addAttribute("inner", "" + joinTable.getInnerTableReferences().contains(vt.getTableReference()));
        writer.addAttribute("class", ValueTableReference.class.getName());
        context.convertAnother(vt);
        writer.endNode();
      } else {
        throw new RuntimeException("Unexpected table type in JoinTable tables list: " + vt.getClass().getSimpleName());
      }
    }
    writer.endNode();
  }

  @Override
  public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
    reader.moveDown();
    List<ValueTable> tables = new ArrayList<>();
    List<String> innerTableReferences = new ArrayList<>();
    while(reader.hasMoreChildren()) {
      reader.moveDown();
      String inner = reader.getAttribute("inner");
      ValueTable vt = (ValueTable) context.convertAnother(context.currentObject(), ValueTableReference.class);
      tables.add(vt);
      if (inner != null && "true".equals(inner)) {
        innerTableReferences.add(((ValueTableReference)vt).getReference());
      }
      reader.moveUp();
    }
    reader.moveUp();
    return new JoinTable(tables, innerTableReferences,false);
  }
}