The Commerce Layer

Before any invocation of commerce services a connection between a Client and a Server has to be established. Then an instance of a CL... Service class to be used has to be created. Now its methods may be called.

The Commerce Layer currently consists of the following essential elements:

• one basic CL Connectivity CLConnection class
• one basic CL Services class CLServices class
• one basic CL Service utility CLContentData class
• several basic CL Services classes having been derived from CLServices

Class: CLConnection

• is to be instantiated before any calls to commerce layer services.
• establishes a connection between a client and a server.

There are two class constructors, one for either side:

A paramaterized one and one without any parameters to be passed to. The client's side, i.e. the side that initially wants to send data will have to use the parameterized version in order to identify itself to its counterpart by its address and name and other id values.

The initial receiver's side (usually a server) invokes the unparameterized version since it will get all the address/administration information necessary an initial sender (usually a client) that wants to create a connection.

Class: CLServices

Commerce Layer Services

• Certification (not yet implemented, currently performed by security attributes for send/receive)
• Data
• General
• Offer
• OfferRequest
• Order
• OrderConfirm
• OrderPay
• OrderPayConfirm
• Pay

Before a certain service may be invoked an instance of its class has to be created. Each service contains a send and a receive method. Both methods require a previously instantiated CLConnection class object to work properly.

Class: CLContentData

The documentation includes an index and a tree depicting the class structure.

In addition to the classes mentioned above, the following classes (among others) are also defined:

Helper Classes

• CLContentData.java
• Security.java

Exceptions

• CLException.java