in src/main/java/org/apache/commons/dbutils/wrappers/SqlNullCheckedResultSet.java [385:397]
public Object invoke(final Object proxy, final Method method, final Object[] args)
throws Throwable {
final Object result = method.invoke(this.resultSet, args);
final Method nullMethod = NULL_METHODS.get(method.getName());
// Check nullMethod != null first so that we don't call wasNull()
// before a true getter method was invoked on the ResultSet.
return nullMethod != null && this.resultSet.wasNull()
? nullMethod.invoke(this, (Object[]) null)
: result;
}