Close Cache Stream to Release Lock

Note

This feature is only available in NCache Enterprise Edition.

The stream should be closed after being used in any mode in order to release the lock. This section explains the closing of a stream in NCache.

Pre-Requisites

• Include the following namespaces in your application:
  • Alachisoft.NCache.Runtime.Caching
  • Alachisoft.NCache.Client
  • Alachisoft.NCache.Runtime.Exceptions
• Cache must be running.
• Make sure that the data being added is serializable.
• To ensure the operation is fail safe, it is recommended to handle any potential exceptions within your application, as explained in Handling Failures.

try
{
    // Pre-condition: Cache is already connected
    // Generate a unique cache key
    string key = "StreamKey";

    // Initialize CacheStream object
    CacheStream cacheStream = null;

    // Set StreamMode object to Read mode
    StreamMode streamMode = StreamMode.Read;

    // Provide the streamMode object to cachestreamAttributes object 
    var streamAttributes = new CacheStreamAttributes(streamMode);

    // Use GetCacheStream to set streamAttributes against the specified key 
    cacheStream = cache.GetCacheStream(key, streamAttributes);

    // Specify cacheStream's length
    int dataSize = Convert.ToInt32(cacheStream.Length);

    // Specify buffer size
    byte[] dataToRead = new byte[dataSize];      

    // Read data from buffer
    cacheStream.Read(dataToRead, 0, dataSize);

    //close stream
    cacheStream.Close();
}
catch (OperationFailedException ex)
{
    // Exception can occur due to:
    // Connection Failures
    // Operation Timeout
    // Operation performed during state transfer
}
catch (Exception ex)
{
    // handle exception
    // This includes StreamException
}

Reading or writing a stream that was previously in use throws exception i.e. StreamAlreadyLockedException, if it was not closed properly.

Additional Resources

NCache provides sample application for streaming at:

• GitHub

• Shipped with NCache: %NCHOME%\samples\dotnet\Streaming

See Also

Continuous Query
Read/Write Streams
Add and Update Data with Streams
Retrieving Data from Streams
Security and Encryption