class AbstractTextDataSourceDefinition extends DataAdapterDefinition {

    protected Class<? extends Number> getNumericType(Object value, JRDesignField field) {
        Number number = null;

        if (value instanceof Number) {
            number = (Number) value;

        } else if (value instanceof String) {

            number = stringToNumber((String) value);
        }

        return number == null ? null : number.getClass();
    }

}