ParseException on doing Unit.valueOf(NonSI.BYTE.times(1024).toString());

[Rohit Kumar]

I am trying to write code which can serialize javax.measure.unit.Unit instances into JSON. For this I am using the Jackson object mapper. The object mapper can't directly serialize Unit instances due to a self-reference, so instead I store a String representation of the Unit.

While serializing I do something like

 String jsonString = serialize(unit.toString());

While deserializing I do:

 String unitString = deserialize(jsonString);
 Unit<?> unit = Unit.valueOf(unitString);

This works for most of the basic units, but not for something like say "NonSI.Byte.times(1024)". Essentially the following code throws a ParseException:

Unit.valueOf(NonSI.BYTE.times(1024).toString());

Does anyone know how to solve this?

[Werner Keil]

Rohit,

Thanks a lot for your message and interest. Could you attach a running example, e.g. a few classes demonstrating this behavior?

A word of caveat, given the JSR (275) as it was way before its time and Java's capabilities (you may have heard, Oracle announced a more solid type system, which goes in a direction where new technologies and standards like it could make more sense, for Java 10, due not before 2017, that's 5 years from now!) back then, cannot actively be maintained.

You could get support via the JScience mailing lists like unitsof...@jscience.java.net since the current stable JScience version uses this stage of the JSR. I suppose you're using the JScience implementation or distribution for JSR 275 or do you use it by itself? There's also an equivalent to this group: us...@jscience.java.net

Beside possible patches or fixes for JScience 4, have you considered using Unit-API, the framework those groups and mailing lists were mainly created for?

Eclipse UOMo is in incubator at Eclipse.org, but has been around for 1.5 years now in a stable condition. JScience 5 also building on Unit-API is available in source code, but I cannot say, when a binary will be released.

Kind Regards,

Werner Keil

UOMo Lead