What's the term for an isolated set of references?

I know I learnt this on the SCJP syllabus, but it escapes me.

Wha开发者_运维问答t's the term for a set of objects that refer to each other but are no longer accessible from your program (and are thus eligible for garbage collection)?

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Your objects are unreachable (i.e. they cannot be reached from any current stack frame and can thus be considered to be garbage). In the specific case of a set of mutually-referencing objects, these can be said to have cyclic references

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Island of Isolation