code: public String foreignKeyColumnName(
  			String propertyName, String propertyEntityName, String propertyTableName, String referencedColumnName
  	) {
  		String header = propertyName != null ? unqualify( propertyName ) : propertyTableName;
  		
  		checkState(header != null, "NamingStrategy not properly filled");
  		
  		return columnName( header ); //+ "_" + referencedColumnName not used for backward compatibility
  	}
docs: Return the property name or propertyTableName