25 Defining Conversations

This chapter describes how to create and configure conversations in your BPM project. it also describes how to view and use a collaboration diagram.

This chapter includes the following sections:

• Section 25.1, "Introduction to Conversations"

• Section 25.2, "Understanding the Different Types of Conversations"

• Section 25.3, "Creating Conversations"

• Section 25.4, "Defining Conversations for a BPMN Element"

• Section 25.5, "Viewing the Collaboration Diagram"

25.1 Introduction to Conversations

Conversations group the message exchange between two or more processes. The message exchange between processes is called collaboration.

Conversations define the state of a collaboration between two participants. You must use them when a process needs to have multiple parallel conversations with different instances of the same process or service, for example within a multi-instance subprocess.

A process instance may need to communicate with different instances in another process. For example, a procurement process may need to interact with two different instance in a supplier process, each representing a different item. You can model this message exchange using conversations.

Within a process you can define multiple conversations that you can reuse amongst the flow objects in that process.

The members of the collaboration are called participants. The participants in a collaboration can be one of the following:

• BPMN processes

• BPEL processes

• Human Tasks

• Business Rules

• External References

Collaboration diagrams allows you to view the process flow together with the interactions your process has with other participants in the conversation.

25.1.1 Defining the Default Conversation

Your BPM project defines a conversation by default. If you do not want to define multiple conversations you must use this default conversation to gather all the message exchange amongst the processes in your project.

You can only define one default conversation per project. However you can modifiy your project to use a different default conversation than the one it uses by default. For more information on how to do this, see.

25.2 Understanding the Different Types of Conversations

The different types of conversations allow you to specify the different types of interaction your process can stablish with other processes or services.

The following list describes the different types of conversations:

• Define Interface: use this type to define the operations that other services and processes can invoke to interact with a BPMN process.

• Use Interface: use this type to configure your process to use an interface from a component in the Business Catalog.

• Process Call: use this type to invoke another BPMN process.

• Service Call: use this type to invoke a service defined in your BPM project.

For more information on how to communicate your process with other processes or services, see the following chapters:

• Chapter 22, "Communicating With Other BPMN Processes and Services"

• Chapter 23, "Defining the Process Interface"

25.3 Creating Conversations

Conversations enable you to group the message exchange between the processes in your BPM project.

25.3.1 How to Create a Conversation

You can create a conversation to model the message exchange between a process instance and the instances in another process or service.

To create a conversation:

1. In the BPM Project Navigator, select a process from the project in which you want to define the correlation.

2. In the Structure window, right-click the Conversations node.

3. Select New.

   The Create Conversation dialog appears.

4. Enter a name to identify the conversation.

5. If you want this conversation to be the default conversation for this project, select Default Conversation.

6. From the Type list select the type for this conversation.

   Available types are:

   • Define Interface

   • Use Interface

   • Process Call

   • Service Call

   For more information about the different types of conversations, see ....

7. If you want to expose this conversation as a SOAP service, select Expose as a SOAP Service.

8. Click OK.

25.3.2 Changing the Project Default Conversation

You can change the project default conversation.

To change the project default conversation:

1. In the BPM Project Navigator, select a process from the project in which you want to define the correlation.

2. In the Structure window, expand the Conversations node.

3. Right-click the current default conversation.

4. Select Edit.

   The Edit Conversation dialog appears.

5. Deselect the Default Conversation check box.

6. Click OK.

7. In the Structure window, right-click the conversation you want to configure as default.

8. Select Edit.

   The Edit Conversation dialog appears.

9. Select the Default Conversation check box.

10. Click OK.

25.4 Defining Conversations for a BPMN Element

The BPMN elements you use to communicate a process with other processes or services require you to define a conversation. The defined conversation groups the messages exchanged between the processes and services within a BPM project.

The BPMN elements that require you to define a conversation are:

• Message Events

• Send and Receive Tasks

• Signal Events

25.4.1 How to Define a Conversation for a BPMN Element

To define a conversation for a BPMN element:

1. Right-click the BPMN element.

   The Properties dialog appears.

2. Click the Implemenation tab.

3. Click the Browse button next to the Conversation field.

   The Conversation dialog appears.

4. Select a conversation from the list.

   To search for a conversation, enter part of the name or the complete name in the Search field.

   To create a new conversation, click the New button. For more information on how to create a new conversation, see Section 25.3, "Creating Conversations".

5. Click OK.

   The Message Exchange section displays different fields according to the type of conversation you selected.

6. Configure the Message Exchange section.

   For more information on how to configure the Message Exchange section, see ....

7. Click OK.

25.4.2 What Happens When You Define a Conversation for a BPMN Element

You can define conversations at process or subprocess level, this determines the visibility scope of the conversation from a specific instance.

25.5 Viewing the Collaboration Diagram

The collaboration diagram shows the flow of your process and how that process interacts with other processes or services in the same diagram.

25.5.1 How to View the Collaboration Diagram

You can view the collaborations in your process using the collaboration diagram.

To view the collaboration diagram:

1. Open the BPMN process.

2. In the BPMN process editor, click the Collaboration tab located at the bottom next to the Designer tab.

   The collaboration diagram for the selected process appears.

25.5.2 How to Hide a Collaboration

You can hide a collaboration so that you are able to focus on the rest of the collaborations in the diagram.

To hide a collaboration:

1. In the Collaboration Diagram, right click over a participant of the conversation.

2. Select Hide Conversation.

   The selected participant disappears from the Collaboration Diagram.

25.5.3 How to Show a Collaboration

You can show a conversation that was previously hidden.

To show a collaboration:

1. In the Collaboration Diagram, right-click a participant of the conversation.

2. Select Show Conversation.

   The previously hidden conversation appears from the Collaboration Diagram.