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causes the specified object or objects not to be released when the current JavaBlock ends.
KeepJavaObject[object, Manual]
causes the specified object to escape from all enclosing JavaBlock blocks, meaning that the object will only be released if you manually call ReleaseJavaObject.
  • To use KeepJavaObject, you first need to load J/Link using Needs["JLink`"].
  • KeepJavaObject allows an object to "escape" from the current JavaBlock.
  • KeepJavaObject only has an effect if the object was in fact slated to be released by the current block.
  • KeepJavaObject causes the object to be promoted to the "release" list of the next-enclosing JavaBlock, if there is one, so it will be released when that block ends (unless you call KeepJavaObject again in the outer block).