axon-ivy-data

name	axon-ivy-data
description	Rules and patterns for Axon Ivy data classes (.d.json files).

When to Use

• Creating or editing .d.json data class files (master data for processes or dialogs)
• Adding fields to an existing data class
• Setting up the data layer for a new workflow process

Use Together With

• axon-ivy-workflow-guide - Step-by-step workflow creation
• axon-ivy-process - For process that uses these data classes

After Modifying Data Classes

MANDATORY: After creating or modifying any .d.json file, run Maven build to regenerate the Java source classes:

mvn clean install -f <project-directory>/pom.xml

This generates the corresponding Java classes in src_dataClasses/ (for dialog data) or compiles the data class definitions so they are available at runtime. Without this step, the process engine will not see the updated fields.

Data Class Types

Type	Location	Purpose
Master Data	dataclasses/	Workflow state container
Dialog Data	src_dataClasses/	Auto-generated UI bindings

.d.json Schema

See schema.json in this skill folder for full JSON schema reference.

Required fields: simpleName, namespace

Field properties: name (required), type, modifiers, comment, annotations

Modifiers: PERSISTENT, ID, GENERATED, NOT_NULLABLE, UNIQUE, NOT_UPDATEABLE, NOT_INSERTABLE, VERSION

Field Type Reference

Type	JSON value	Notes
String	omit "type" (default)	Text, IDs, dates returned by AI
Boolean	"Boolean"	true/false flags
Integer	"java.lang.Integer"	Whole numbers, quantities
Double	"java.lang.Double"	Prices, amounts, rates
BigDecimal	"java.math.BigDecimal"	High-precision financial calculations
LocalDate	"java.time.LocalDate"	Date only (yyyy-MM-dd)
LocalDateTime	"java.time.LocalDateTime"	Full timestamp
File	"java.io.File"	Uploaded file handle
InputStream	"java.io.InputStream"	File content stream (for AI extraction)
List of objects	"List<com.example.Item>"	Use fully-qualified type name
List of strings	"List<String>"	Simple string lists
Nested object	"com.example.Address"	Use fully-qualified class name
Enum	"com.example.Status"	Use fully-qualified enum name

Double vs BigDecimal: Use Double for display and simple calculations. Use BigDecimal only for strict financial rounding requirements.

Dates from AI extraction: Prefer String (AI returns ISO format strings). Parse to LocalDate in a Script element only when needed for business logic comparisons.

.d.json Examples

Basic Master Data

{
  "$schema" : "https://json-schema.axonivy.com/14.0-dev/project/data-class.json",
  "simpleName" : "OnboardingData",
  "namespace" : "hr.onboarding",
  "fields" : [ {
    "name" : "onboarding",
    "type" : "hr.onboarding.model.Onboarding",
    "modifiers" : [ ]
  }, {
    "name" : "status",
    "modifiers" : [ ]
  } ]
}

With Comments

{
  "$schema" : "https://json-schema.axonivy.com/14.0-dev/project/data-class.json",
  "simpleName" : "HiringData",
  "namespace" : "hr.hiring",
  "fields" : [ {
    "name" : "candidate",
    "type" : "hr.hiring.model.Candidate",
    "modifiers" : [ ],
    "comment" : "The candidate being processed"
  }, {
    "name" : "approved",
    "type" : "Boolean",
    "modifiers" : [ ]
  } ]
}

With List Type

{
  "$schema" : "https://json-schema.axonivy.com/14.0-dev/project/data-class.json",
  "simpleName" : "ProjectData",
  "namespace" : "project.management",
  "fields" : [ {
    "name" : "tasks",
    "type" : "List<project.model.Task>",
    "modifiers" : [ ]
  }, {
    "name" : "notes",
    "type" : "List<String>",
    "modifiers" : [ ]
  } ]
}