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The ordering problem can be dangerous when dealing with native code. For example, if object A references object B (either directly or reflectively) and the latter gets finalized first, A's finalizer may end up dereferencing dangling native pointers. To impose an explicit ordering on finalizers, make sure that B is remains reachable before until A's finalizer has concluded. This can be achieved by adding a reference to B in some global state variable and removing it as soon as when A's finalizer gets executedexecutes. An alternative is to use the java.lang.ref references.
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