The lastError attribute is the last error that occurred. You can tear off the lastError attribute to access the error information.

The replyQueue attribute represents the queue that will be used for either input or output depending on how the server attribute is set. If the server attribute is set to true then the queue is used for output (server), otherwise it is used for input (client).

The replyQueueAsList attribute represents the distribution list that will be used for output. Use this attribute if you have set up your connection to use distribution lists; otherwise, use the replyQueue attribute.

The requestQueue attribute represents the queue that will be used for either input or output depending on how the server attribute is set. If the server attribute is set to true then the queue is used for input (server), otherwise it is used for output (client).

The requestQueueAsList attribute represents the distribution list that will be used for output. Use this attribute if you have set up your connection to use distribution lists; otherwise, use the requestQueue attribute.

The self attribute represents the part itself, and you cannot change the basic definition of a part. In general, the self attribute is a read-only attribute, and is used for passing a value or values to another part. It is not used for receiving any values.

For example, you can connect the self attribute of an Ordered Collection part to the items attribute of a List part. The Ordered Collection part does not change to a different type of part because of the connection. Instead, the Ordered Collection part populates the List part with the items that it contains.

You can use the self attribute in an attribute-to-attribute connection, as a parameter in an event-to-action connection, or wherever an attribute can be used.

The server attribute determines if the application is used as a server or a client. If the server attribute is true the application acts as a server. If it is set to false it acts as a client. The value of this boolean also determines how the reply and request queues will be used.