public interface Synchronizer
An interface controlling synchronization of configuration instances.
Configuration object derived from
has an associated
Synchronizer object. Before an operation on the
configuration is performed (e.g. a property read or an update), the
Synchronizer is invoked. Depending on the concrete implementation of
Synchronizer used, the configuration can be made thread-safe.
Whether a configuration has to be thread-safe or not is a matter of a
concrete use case. For instance, an application that just reads some
configuration settings on startup does need a thread-safe configuration
implementation. A configuration in contrast which is shared between multiple
components and updated concurrently should better be thread-safe. In order to
satisfy both kinds of use cases, the support for thread-safety has been
extracted out of the configuration implementation and refactored into this
Synchronizer interface. By assigning different
implementations to a configuration instance, the instance's support for
concurrent access can be adapted to the concrete use case.
The methods defined by this interface are similar to a read-write
Synchronizer is notified when read or write operations
start and end. A concrete implementation can then apply a specific policy to
decide when threads need to block or when access to the configuration for the
desired operation is granted.
|Modifier and Type||Method and Description|
Synchronizerthat the current thread is going to start a read operation on the managed configuration. This call can block if a concrete implementation decides that the thread has to wait until a specific condition is fulfilled.
Synchronizerthat the current thread has finished its read operation. This may cause other waiting threads to be granted access to the managed configuration.
Synchronizerthat the current thread is going to start a write operation on the managed configuration. This call may block. For instance, a concrete implementation may suspend the thread until all read operations currently active are finished,
Synchronizerthat the current thread has finished its write operation. This may cause other waiting threads to be granted access to the managed configuration.
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