java - XSD schema changes, XSLT and backwards compatibility -


this more of high level question using jaxb , xslt, try gain more of understanding of need do, , need learn more about.

i have inherited application has java class files generated xsd schema (using jaxb), stuff, writes 1 of these objects serialized 'save file'.

i need make changes xsd, of course mean of generated classes updated. however, still need able load old serialized saved files backwards compatibility - mean need maintain copy of current xsd, , generated class files in order load old serialized save files? have suggested way can this, if must able load old files?

for future version of xsd, intend output saved files xml, , use xslt transform file before unmarshalling xml, think work, mentioned in thread how should manage different incompatible formts of xml based documents. doesn't me older serialized files though - ideas?

thanks.

probably main drawback of jaxb, , of data binding in general, makes schema evolution cumbersome. xml technology people expect change , extend schema/data model frequently, whereas in java hard-coded , hard change. use of xml-oriented languages xslt , xquery big advantage in such situations.

saving persistent data in form of serialized java objects seems perverse me. before move new schema format, convert xml. whole point of xml data in format far more durable, , not dependent on continued existence of software created it.


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