Wolfram Language & System 10.0 (2014)|Legacy Documentation

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causes all new Java objects returned to the Wolfram Language during the evaluation of expr to be released when expr finishes. It is an error to refer to such an object after JavaBlock ends.


  • To use JavaBlock, you first need to load J/Link using Needs["JLink`"].
  • JavaBlock is a way to mark a set of objects as temporary so they can be automatically cleaned up when the block of code ends.
  • JavaBlock affects only new objects, not additional references to ones that have previously been seen.
  • If a JavaBlock returns a single JavaObject as a result, that object will not be released.