what is JCR in java and spring -

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i have been learning java spring hibernate mvc 3 months , got pretty idea of . have not understood jcr means.

i mean e.g in simple webiste in spring mvc part can done in jcr

jcr alternative persistence mechanism used in place of jpa (hibernate), hides jdbc application. in theory, java classes have in model might remain same have now. however, if classes in model came because needed model lower-level data structures jpa, these classes might not needed jcr.

you'd need reason replace existing use of jpa jcr. example, may have discovered using jpa requires jumping through lot of hoops , doing things you'd not need do.

having said that, jcr has advantages , capabilities not otherwise found in jpa:

  1. jcr supports structured data, unstructured data, , in between. jcr allows flexible schema , can nosql-ish. jpa structured, fixed schema.
  2. jcr hierarchical - use cases extremely hierarchical, , doing relational model can difficult/expensive
  3. jcr has built-in events
  4. most jcr implementations can store content in variety of systems. can access , federate existing content in other systems.
  5. no length limitation of string values
  6. jcr has full-text search support
  7. jcr has multiple query languages, including jcr-sql2 (very sql-like)
  8. there libraries map java classes node structures, , similar jpa/hibernate

it depends on whether these features beneficial application.


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