Data Classes

This chapter deals with Axon Ivy Data Classes. A Data Class generally holds the data that flows through your business or User Dialog process. You can build complex data structures in your Data Classes. Use composition to split up your data if the amount of your data is getting large.

Types of Data Classes

There are four kinds of Data Classes in Axon Ivy.

Global Data Classes

The global Data Classes are located in the Data Class node in your project tree. They are accessible in your project and projects depending on it.

User Dialog Data Class

Each User Dialog has its Data Class. This class holds the data that flows through your User Dialog process. In your User Dialog Data Class, you can define fields with a type of a global Data Class. The User Dialog Data Class is visible only in the associated User Dialog Process.

Web Service (WS) Data Classes

Axon Ivy generates a Web Service Data Class automatically when you create a Web Service configuration. The Web Service Data Class, like a global Data Class, is accessible in your project and projects depending on it. Use this Data Class to communicate with your Web Services.

Entity Classes

Entity Classes are like Global Data Classes but with additional information on where and how to store the data of a class and its attributes to a relational database.

New Data Class Wizard

The New Data Class wizard lets you create a new global Data Class.

New Data Class Wizard

Accessibility

File > New > Data Class

Features

Project Name

Choose the name of the project the new Data Class should belong to.

Namespace

Choose a namespace for your Data Class. The namespace lets you create a structure to organize your data. Use the dot character ‘.’ to separate the folders. The namespace will be visible in the Axon Ivy project tree.

Data Class Name

Enter the name of your Data Class. Do not use a Data Class Name twice in your project, it may get confusing if you do so.

Data Class Editor

The Axon Ivy Data Class editor lets you configure the process data objects of Axon Ivy. The process data is the data that flows through your processes. It represents the state of the respective process.

Use this editor to add new data fields to your process data class, to change the type of a field or document your Data Class or Data Class Field.

Data Class Editor

Accessibility

1. Axon Ivy Project Tree > double click on a Data Class entry in the tree.

2. New > Data Class > then the editor opens if the class has been created successfully

Attributes

The attributes table specifies the Data Class contents.

Comment

Use this field to document your data class

Annotations

You can use annotations to control certain behaviors:

BusinessCaseData

Objects having the BusinessCaseData annotation are stored in the Business Data Store (ivy.repo) in the context of the current business case. See Business Case Data for additional information.

Table Actions

Adds a new attribute to the table. You can also add new attributes by clicking on an empty row.

Deletes the selected attribute.

Reorders the selected attributes. The order influences just the presentation and has no implications on the logic.

Toggles the value change breakpoint for selected attribute. The attribute icon shows that a breakpoint is installed on an attribute. Find more information on value change breakpoints in chapter Breakpoints.

Name Column

Enter the name of your attribute. The name should not contain any special characters or spaces.

Tip

You may already specify the type of the attribute here by adding a colon ‘:’ to the attribute name, followed by the desired type (e.g., myDateAttribute:Date).

The entered type is used as a search filter. The following examples use a data or Java class with the name ch.ivyteam.demo.Person:

• person:Person results in person, ch.ivyteam.demo.Person.

• personList:List<Person> results in personList, List<ch.ivyteam.demo.Person>.

• javaPersonList:java.u.List<Person> results in person, java.util.List<ch.ivyteam.demo.Person> (Here, a prefix of the package name java.u is used as a filter instead of the full qualified name java.util).

• timestamp:Timestamp displays the type selection dialog because there are multiple types matching the type name Timestamp.

Type Column

Enter the type of the attribute or press to bring up the Data Type Browser.

Persistent Column

Decide if the data should be persistent between task switches. If the data is not set to be persistent, then you lose all information if the execution of the process passes a task switch process element.

Note

You can remove this flag on attributes if their value is stored in the business data repository, in persistence, or if the data is only used temporarily within a task.

Attribute Refactoring

The Data Class editor supports Data Class attribute refactoring.

Combine Into New Data Class Refactoring

Over time, the number of attributes in a Data Class may become excessive. This decreases the maintainability and re-usability of your process logic. Therefore, the editor allows you to extract multiple attributes from an existing Data Class into a new Data Class. The extracted attributes will be replaced with a delegate field for the new Data Class.

If you have a Data Class that describes a person, you could extract the attributes that belong to the address part into an extra address Data Class.

Before Refactoring	After Refactoring

Start Refactoring

Select the attributes to extract in the Data Class attribute table. Open the context menu of the selected attributes. Choose Combine to Data Class to open the refactoring wizard.

Wizard Page 1 - Define the new Data Class

The first refactoring wizard page lets you define the location and name of the Data Class. The checkbox ‘Include non-type safe refactorings within Web Pages (CMS)’ enables the refactoring of JSP (macro) expressions within Web Pages. Web Page modifications are not type-safe: Attributes collected as change candidates may be wrong. So these changes should be inspected in detail in the refactoring preview (page 2) and tested manually.

Wizard Page 2 - Preview modifications

The second page previews all changes that will be applied to your artifacts. You can inspect most of the changes within the textual compare view on the lower part of the page.

The refactoring will modify all programmatic references to attributes. Statements written in Java, IvyScript, JSP or El-Expressions may be changed by this refactoring.