public T convertColumnValue()

in empire-db/src/main/java/org/apache/empire/commons/ValueUtils.java [783:839]
46 lines of code
23 McCabe index (conditional complexity)

    public <T> T convertColumnValue(ColumnExpr column, Object value, Class<T> vt)
        throws ClassCastException
    {
        // check
        if (value==ObjectUtils.NO_VALUE)
            throw new InvalidValueException(value);
        // use a is
        if (vt==Object.class)
            return ((T)value);
        // convert
        if (vt==String.class)
            return (T)toString(value);
        if (vt==Integer.class)
            return (T)(value!=null ? toInteger(value) : INTEGER_ZERO);
        if (vt==Long.class)
            return (T)(value!=null ? toLong(value) : LONG_ZERO);
        if (vt==Double.class)
            return (T)(value!=null ? toDouble(value) : DOUBLE_ZERO);
        if (vt==BigDecimal.class)
            return (T)(value!=null ? toDecimal(value) : BigDecimal.ZERO); // required for compatibility
        if (vt==Boolean.class)
            return (T)(value!=null ? toBoolean(value, false) : Boolean.FALSE);
        // enum
        if (vt.isEnum())
        {   // Null
            if (value==null)
                return null;
            // convert
            Class<? extends Enum<?>> enumType = (Class<? extends Enum<?>>)vt;
            try {
                // Convert to enum, depending on DataType
                boolean numeric = column.getDataType().isNumeric();
                return (T)toEnum(enumType, (numeric ? toInteger(value) : value));
        
            } catch (Exception e) {
                // Illegal value
                log.error("Unable to resolve enum value of '{}' for type {}", value, enumType.getName());
                throw new FieldIllegalValueException(column.getUpdateColumn(), String.valueOf(value), e);
            }
        }
        // Date conversions
        try {
            // DateTimeFormatter.ISO_LOCAL_DATE_TIME
            if (vt==Date.class)
                return (T)toDate(value);
            if (vt==Timestamp.class)
                return (T)toTimestamp(value);
            if (vt==LocalDate.class)
                return (T)toLocalDate(value);
            if (vt==LocalDateTime.class)
                return (T)toLocalDateTime(value);
        } catch (ParseException | DateTimeParseException e) {
            throw new ValueConversionException(Timestamp.class, value, e);
        }
        // something else?
        return convertToJava(vt, value);
    }