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Jungle Exception

Jungle handles exceptions very strictly. If a node throws an exception, the node will be immediately stopped. Exceptions should be thrown whenever a node encounters a problem that would prevent it from continuing. This is useful for displaying when a critical error occurs in your tree and prevent subsequent nodes from running, which could cause even more errors.

You can throw an exception of any type, but it is recommended to use the JungleException class.

An exception can be thrown anywhere at any time within a node.

When to Throw Exceptions?​

You should throw exceptions when a critical error occurs in your nodes that prevents the node from performing its task.

Example​

Let's say you have a node named FindGameObject that finds a game object in the scene and outputs it. Any nodes connected to the output of the FindGameObject node will expect a game object.

Let's say that the FindGameObject node is run and it can't find the game object in the scene. If the node just continues anyways, then all connected nodes would be expecting a game object, except they would be getting null instead.

To prevent this, you should throw an exception if the game object is not found. This will prevent any subsequent nodes from running and more causing errors.

Throwing an Exception​

Throwing exceptions is extremely easy.

You should always throw a JungleException when an error occurs. This will ensure that the error is caught by the error handler. You can also pass a message to the exception to display in the console.

throw new JungleException("YOUR MESSAGE");

You can throw Jungle exceptions inside any inherited Jungle Node method.

Example​

Here's an example of a node that sets the position of a transform to the origin. If the inputted transform is null, then an exception is thrown.

using Jungle;
using UnityEngine;

public class ExceptionNode : IONode<Transform>
{
    protected override void OnStart(Transform transform)
    {
        if (transform == null)
            throw new JungleException("Inputted transform is null.");

        transform.position = Vector3.zero;
        CallAndStop(transform);
    }

    protected override void OnUpdate() { }
}