Using the NamedPipe Connection Class

Within JADE, you establish a connection and send or receive data programmatically. The Connection class defines all of the methods that you require for external communications. The NamedPipe class is a subclass of the Connection class and is specifically for external communication through the Windows NamedPipe facility. When using the Connection class, note the following restrictions.

• The Connection class hides underlying implementation and transport-dependent details. Any exception conditions result in an exception of type ConnectionException being raised.

• Connection objects must be transient. If an attempt is made to create a persistent Connection object, an exception is raised.

• Asynchronous methods have a receiver object and a message (method name) specified as parameters. When the method completes, the specified (callback) method of the specified object is called. The callback method is assumed to match the signature required by the calling asynchronous method.

The NamedPipe class supports both synchronous and asynchronous operations, as follows.

• As the functionality of the timeout property in the Connection class is not supported in the NamedPipe class, synchronous methods that time out will wait forever for completion.

• Asynchronous methods have a receiver object and a message (method name) specified as parameters. When the method (I/O) completes, the specified (callback) method of the object is called. The callback method must match the signature required by the calling asynchronous method.

Only one synchronous or asynchronous read operation can be in effect at each end of each instance of the pipe. Multiple asynchronous write operations can be in effect.

Opening the server end of the pipe waits until the other end of the pipe is connected. Opening the client end of the pipe fails immediately if the server end of the pipe has not been offered.