Lock Type Compatibility
The valid concurrent lock combinations are shown in the following table.
| Exclusive | Update | Reserve | Shared | |
|---|---|---|---|---|
| Exclusive | No | No | No | No |
| Update | No | No | No | Yes |
| Reserve | No | No | No | Yes |
| Shared | No | Yes | Yes | Yes |
To summarize:
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A JADE object can have multiple shared locks, but only one reserve, update, or exclusive lock.
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Shared locks are compatible with reserve locks and update locks, but not with exclusive locks.
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A reserve lock is compatible with shared locks, but not with update locks or exclusive locks.
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An exclusive lock is not compatible with any other lock type.
