code: public void clear() {
  		// clear properties
  		List<String> ownProps = getOwnProperties();
  		
  		for (String key : properties.keySet().toArray(new String[]{})) {
  			if (ownProps.contains(key)) {
  				Object value = properties.get(key);
  				if (value instanceof JsonCollection) {
  					JsonCollection entity = (JsonCollection)value;
  					entity.clear();
  				} else {
  					remove(key);	
  				}
  			} else {
  				remove(key);
  			}
  		}
  		
  		// clear fields
  		for (Field field : getFields(this.getClass())) {
  			if (field != null && JsonCollection.class.isAssignableFrom(field.getType())) {
  				try {
  					field.setAccessible(true);
  					JsonCollection entity = (JsonCollection) field.get(this);
  					entity.clear();
  				} catch (Exception e) {
  					log.error(e);
  				}
  			}
  		}
  		
  		// clear sort order
  		sortOrder.clear();
  	}
docs: /*
  (non-Javadoc)
  
  @see com.dubture.getcomposer.core.entities.JsonCollection#clear()