# Interface ITransitionBuilder

OptimaJet.Workflow.Core.Model.Builder.ITransitionBuilder

Provides a fluent API for configuring a [TransitionDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) within a process scheme.

Namespace: [OptimaJet.Workflow.Core.Model.Builder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/)

```csharp
public interface ITransitionBuilder : IProcessDefinitionBuilder
```

## Type Hierarchy

-   ITransitionBuilder Current type
    -   Base interfaces
        -   [IProcessDefinitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/IProcessDefinitionBuilder/)
    -   Derived interfaces
        -   [ITransitionCommandBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionCommandBuilder/)
        -   [ITransitionConditionsBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionConditionsBuilder/)
            -   [ITransitionConditionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionConditionBuilder/)
            -   [ITransitionExpressionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionExpressionBuilder/)
        -   [ITransitionParallelFinalizeBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionParallelFinalizeBuilder/)
        -   [ITransitionParallelStartBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionParallelStartBuilder/)

## Properties

`TransitionDefinition Transition { get; }` 

Gets the [TransitionDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) currently being configured.

## Methods

`ITransitionBuilder Name(string name)` 

Sets the transition name.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `name` | `String` | The name to assign. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder From(ActivityDefinition activityDefinition)` 

Sets [TransitionDefinition.From](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/), the source activity from which the transition starts.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `activityDefinition` | `ActivityDefinition` | The source [ActivityDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ActivityDefinition/). |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder To(ActivityDefinition activityDefinition)` 

Sets [TransitionDefinition.To](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/), the target activity to which the transition leads.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `activityDefinition` | `ActivityDefinition` | The target [ActivityDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ActivityDefinition/). |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder Auto()` 

Sets [TransitionDefinition.Trigger](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [TriggerDefinition.Auto](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TriggerDefinition/) and clears [TransitionDefinition.Restrictions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/).

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder TriggeredByTimer(TimerDefinition timerDefinition)` 

Sets [TransitionDefinition.Trigger](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to a [TriggerType.Timer](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TriggerType/) trigger and clears [TransitionDefinition.Restrictions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/).

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `timerDefinition` | `TimerDefinition` | The [TimerDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TimerDefinition/) associated with the trigger. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionCommandBuilder TriggeredByCommand(CommandDefinition commandDefinition)` 

Sets [TransitionDefinition.Trigger](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to a [TriggerType.Command](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TriggerType/) trigger.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `commandDefinition` | `CommandDefinition` | The [CommandDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/CommandDefinition/) associated with the trigger. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionCommandBuilder` | An [ITransitionCommandBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionCommandBuilder/) for configuring [TransitionDefinition.Restrictions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/). |

`ITransitionCommandBuilder UpdateCommandTrigger()` 

Opens command-specific configuration when [TransitionDefinition.Trigger](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) is a [TriggerType.Command](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TriggerType/) trigger.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionCommandBuilder` | An [ITransitionCommandBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionCommandBuilder/) for configuring [TransitionDefinition.Restrictions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/). |

### Exceptions

| Type | Description |
| --- | --- |
| `InvalidOperationException` | The transition does not have a [TriggerType.Command](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TriggerType/) trigger. |

`ITransitionBuilder Direct()` 

Sets [TransitionDefinition.Classifier](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [TransitionClassifier.Direct](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionClassifier/), classifying the transition as forward.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder Reverse()` 

Sets [TransitionDefinition.Classifier](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [TransitionClassifier.Reverse](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionClassifier/), classifying the transition as backward or corrective.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder DirectionNotSpecified()` 

Sets [TransitionDefinition.Classifier](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [TransitionClassifier.NotSpecified](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionClassifier/).

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionConditionsBuilder Conditional()` 

Begins configuring [ConditionType.Action](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) and [ConditionType.Expression](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) conditions.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionConditionsBuilder` | An [ITransitionConditionsBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionConditionsBuilder/) for configuring the conditions. |

### Remarks

Existing [ConditionType.Always](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) and [ConditionType.Otherwise](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) conditions are removed.

`ITransitionBuilder Always()` 

Replaces [TransitionDefinition.Conditions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) with a single [ConditionType.Always](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) condition.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

### Remarks

Also sets [TransitionDefinition.ConditionsConcatenationType](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [ConcatenationType.And](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConcatenationType/).

`ITransitionBuilder Otherwise()` 

Replaces [TransitionDefinition.Conditions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) with a single fallback [ConditionType.Otherwise](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) condition.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

### Remarks

Also sets [TransitionDefinition.ConditionsConcatenationType](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [ConcatenationType.And](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConcatenationType/).

`ITransitionBuilder CreateOrUpdateAnnotation(string name, string value)` 

Creates or updates an [Annotation](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/Annotation/) named `name` on the transition, storing `value` unchanged.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `name` | `String` | The name of the annotation. |
| `value` | `String` | The string value to store; it may contain plain text or JSON. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder CreateOrUpdateAnnotation(string name, object value)` 

Creates or updates an [Annotation](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/Annotation/) named `name` on the transition, storing the JSON serialization of `value`.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `name` | `String` | The name of the annotation. |
| `value` | `Object` | The object to serialize and store. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder DeleteAnnotation(string name)` 

Removes all transition annotations named `name`.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `name` | `String` | The annotation name to remove. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder NotParallel()` 

Configures the transition as a [TransitionForkType.NotFork](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionForkType/) transition.

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

### Remarks

Sets [TransitionDefinition.IsFork](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [false](https://learn.microsoft.com/dotnet/csharp/language-reference/builtin-types/bool).

`ITransitionParallelStartBuilder ParallelStart()` 

Configures a [TransitionForkType.ForkStart](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionForkType/) transition by setting [TransitionDefinition.IsFork](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [true](https://learn.microsoft.com/dotnet/csharp/language-reference/builtin-types/bool) and [TransitionDefinition.SubprocessInOutDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [SubprocessInOutDefinition.Start](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/SubprocessInOutDefinition/).

### Returns

| Type | Description |
| --- | --- |
| `ITransitionParallelStartBuilder` | An [ITransitionParallelStartBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionParallelStartBuilder/) for configuring subprocess startup. |

`ITransitionParallelFinalizeBuilder ParallelFinalize()` 

Configures a [TransitionForkType.ForkEnd](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionForkType/) transition by setting [TransitionDefinition.IsFork](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [true](https://learn.microsoft.com/dotnet/csharp/language-reference/builtin-types/bool) and [TransitionDefinition.SubprocessInOutDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [SubprocessInOutDefinition.Finalize](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/SubprocessInOutDefinition/).

### Returns

| Type | Description |
| --- | --- |
| `ITransitionParallelFinalizeBuilder` | An [ITransitionParallelFinalizeBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionParallelFinalizeBuilder/) for configuring subprocess finalization. |

`ITransitionBuilder CreateCommentary(string comment)` 

Sets [TransitionDefinition.UserComment](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/), replacing any current value.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `comment` | `String` | The comment to assign. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder AppendCommentary(string comment)` 

Appends `comment` to [TransitionDefinition.UserComment](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/), inserting a newline before it when the current comment is nonempty.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `comment` | `String` | The comment text to append. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder DeleteCommentary()` 

Sets [TransitionDefinition.UserComment](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) to [null](https://learn.microsoft.com/dotnet/csharp/language-reference/keywords/null).

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder SetX(int? x)` 

Sets [DesignerSettings.X](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/DesignerSettings/) in the transition's [BaseDefinition.DesignerSettings](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/BaseDefinition/).

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `x` | `Nullable<Int32>` | The horizontal coordinate, or [null](https://learn.microsoft.com/dotnet/csharp/language-reference/keywords/null) to clear it. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder SetY(int? y)` 

Sets [DesignerSettings.Y](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/DesignerSettings/) in the transition's [BaseDefinition.DesignerSettings](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/BaseDefinition/).

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `y` | `Nullable<Int32>` | The vertical coordinate, or [null](https://learn.microsoft.com/dotnet/csharp/language-reference/keywords/null) to clear it. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

`ITransitionBuilder Ref(out TransitionDefinition transition)` 

Assigns the [TransitionDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) currently being configured to `transition`.

### Parameters

| Name | Type | Description |
| --- | --- | --- |
| `transition` | `TransitionDefinition` | When this method returns, contains the [TransitionDefinition](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/TransitionDefinition/) being configured. |

### Returns

| Type | Description |
| --- | --- |
| `ITransitionBuilder` | The current [ITransitionBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionBuilder/) instance. |

[Previous ITimerBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITimerBuilder/) [Next ITransitionCommandBuilder](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model.Builder/ITransitionCommandBuilder/)