MapDecomposer.java

package com.orbitz.monitoring.lib.decomposer;

import java.io.Serializable;
import java.util.HashMap;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * Given an instance of <code>Map</object>, this class transforms it to an
 * equivalent <code>Map</code> implementation that is <code>Serializable</code>
 * and is guaranteed to be available in all standard VMs.
 *
 * @author Doug Barth
 */
class MapDecomposer extends AbstractAttributeDecomposerStep {
  private AttributeDecomposer.Step _delegate;

  public MapDecomposer(AttributeDecomposer.Step delegate) {
    _delegate = delegate;
  }

  Serializable createMutableContainer(Object object) {
    Map map = (Map) object;
    return new HashMap(map.size());
  }

  void decomposeInto(Object o, Serializable container, IdentityHashMap alreadyDecomposed) {
    Map map = (Map) o;
    Map returnMap = (Map) container;

    for (Iterator i = map.entrySet().iterator(); i.hasNext();) {
      Map.Entry entry = (Map.Entry) i.next();
      Object key = _delegate.decompose(entry.getKey(), alreadyDecomposed);
      Object value = _delegate.decompose(entry.getValue(),
                         alreadyDecomposed);

      returnMap.put(key, value);
    }
  }
}