NullPointer exception when referencing a JBBPCustomFieldTypeProcessor parsed field

[alastairmccormack]

I've written a JBBPCustomFieldTypeProcessor to parse uint32 fields into Java longs: https://gist.github.com/use-sparingly/ac1539784af7ae7569cd50135016cf2c

It seems to work for single, read all ([_]) and defined length arrays ([1]). However, if I try to reference the value as a field length in a subsequent field I get a nullpointer exception.

Example:

        final JBBPParser sasParser = JBBPParser.prepare(
                ">uint32 keycount;" +
                "key [keycount] {" +
                        "byte[1] contentId; " +
                        "byte[1] keyData; " +
                "}"
        , new Uint32()
        );

        final String inputSHex = "00000001fc05";
        byte inputS[] = Hex.decodeHex(inputSHex.toCharArray());

        final JBBPFieldStruct result = sasParser.parse(inputS);

I get:

Exception in thread "main" java.lang.NullPointerException
	at com.igormaznitsa.jbbp.compiler.varlen.JBBPOnlyFieldEvaluator.eval(JBBPOnlyFieldEvaluator.java:52)
	at com.igormaznitsa.jbbp.JBBPParser.parseStruct(JBBPParser.java:174)
	at com.igormaznitsa.jbbp.JBBPParser.parse(JBBPParser.java:489)
	at com.igormaznitsa.jbbp.JBBPParser.parse(JBBPParser.java:515)
	at Main.main(Main.java:31)

If I replace uint32 with int then it works as expected (until I use a true uint32 value).

[raydac]

could you provide your implementation of uint32? I will make test

[alastairmccormack]

Hi, sorry I included a link in the original question: https://gist.github.com/use-sparingly/ac1539784af7ae7569cd50135016cf2c

[raydac]

thank you very much for the report, I have added your case into tests and fixed the case

[alastairmccormack]

Thanks for the rapid turn around (and for the excellent project!)