Invoke
activities are used to validate that outgoing messages contain data which is
consistent with the data contained within specified correlation set instances.
Correlation is the means by which the BPEL runtime tracks conversations between
a particular process instance and corresponding instances of its partner services.
Consider correlation as a primary key that is used by the BPEL runtime to correlate
incoming and outgoing messages, and route them accordingly.
Also see Chapter 9 for information on Handling Events where correlation is depicted.
BPEL Designer
[ 86 ]
Receive
The Receive activity allows the business process to perform a blocking wait for a
particular message to arrive. Typically the receive activity is the start of a process
instance. It is typically used to receive a message from the client or a callback from a
partner web service. Whenever the process receives a message, a new instance of the
process is created. To keep track of the right process, you need to set the correlation.
You can add any number of receive activities but they should receive messages from
different Partner Links. Also, if you do not create an instance from the Property
Editor window, make sure that you have the Correlations set on Receive activity.
This is because the Receive element must have a valid
child if it
does not have the createInstance="yes" attribute.
Pages:
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97