xstream.fromXML忽略没有的节点

package com.creditharmony.adapter.core.service;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;
import com.thoughtworks.xstream.mapper.MapperWrapper;

public class XStreamEx extends XStream {
 public XStreamEx(DomDriver domDriver) {
 super();
}

@Override
  protected MapperWrapper wrapMapper(MapperWrapper next) {
    return new MapperWrapper(next) {
      @Override
      public boolean shouldSerializeMember(@SuppressWarnings("rawtypes") Class definedIn,
              String fieldName) {
        if (definedIn == Object.class) {
          return false;
        }
        return super.shouldSerializeMember(definedIn, fieldName);
      }
    };
  }

}

XStreamEx xstream = new XStreamEx(new DomDriver(Constant.DEFAULT_CHARSET));