# Add Validation Logic

ONEWEB Smart Forms support **custom validation logic** to ensure data accuracy and enforce business rules before information is processed or saved.

There are **two supported approaches** for adding validation logic:

1. **JavaScript Validation** – client‑side validation
2. **Java Validation** – server‑side validation

Each approach serves a different purpose and can be used independently or together, depending on application requirements.

***

### JavaScript Validation (Client‑Side)

**JavaScript validation** is primarily used for **client‑side checks**, such as:

* Mandatory field validation
* Input format validation
* Immediate user feedback before form submission

JavaScript validation improves usability by preventing invalid data entry at an early stage.

***

#### Attach JavaScript via Entity Action

ONEWEB Smart Forms use **Entity Actions** to attach a JavaScript file to an entity.

> Refer to **Entity Actions** documentation for detailed configuration: <https://docs.oneweb.tech/oneweb/design-and-develop-oneweb-apps/design-and-develop-ux-ui/ux-ui-components/smart-forms/buttons-and-actions>

1. Add a **Module Action** and specify the JavaScript file name.

<figure><img src="https://2015371994-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FMpDjHWFRUtZ5nJcSfVXd%2Fuploads%2FzB2xGAKTwN9hXallLhRs%2F0?alt=media" alt=""><figcaption></figcaption></figure>

***

#### Create JavaScript Validation Logic

1. Open the ONEWEB workspace in **Eclipse IDE**.
2. Create the JavaScript file specified in the Entity Action.
3. Add the validation function inside the file.

<figure><img src="https://2015371994-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FMpDjHWFRUtZ5nJcSfVXd%2Fuploads%2FkotOnVaj43q7df43QrmL%2F1?alt=media" alt=""><figcaption></figcaption></figure>

***

#### Bind Validation to Form Field

1. Build and publish the project to the server.
2. In **App Designer**, edit the target form field.
3. Open the field configuration (pencil icon).
4. Add the JavaScript validation function call in the **Source Tag** property.

<figure><img src="https://2015371994-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FMpDjHWFRUtZ5nJcSfVXd%2Fuploads%2FwvAqwO1AYbqC4U3Ba2gO%2F2?alt=media" alt=""><figcaption></figcaption></figure>

The validation logic is now executed on the client side when the user interacts with the field.

***

### Java Validation (Server‑Side)

**Java validation** is used for **server‑side validation** and is executed **before saving the entity**.\
This approach is critical for enforcing business rules that must not be bypassed, even if client‑side validation is skipped.

***

#### Attach Java Class via Entity Action

1. Add an **Entity Action** to the entity.
2. Specify the Java class name in the **Class Action** property.

<figure><img src="https://2015371994-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FMpDjHWFRUtZ5nJcSfVXd%2Fuploads%2FpY0sDH2DSP9wyg2Y0Tk0%2F3?alt=media" alt=""><figcaption></figcaption></figure>

***

#### Implement Validation Class

1. Open the ONEWEB workspace in **Eclipse IDE**.
2. Create the Java class with the following structure:

* Extend **`ProcessHelper`**
* Implement **`ProcessAction`**

3. Override the `validateResult()` method to define custom validation logic.

**Example (Server‑Side Validation)**

```
public class OrderRequestBackOfficeUpdateMode
        extends ProcessHelper
        implements ProcessAction {

    @Override
    public boolean validateResult() {

        String entityID =
            (String) getRequest()
            .getSession()
            .getAttribute("entityID");

        EntityFormHandler entityForm =
            (EntityFormHandler) getRequest()
            .getSession()
            .getAttribute(entityID + "_session");

        Vector errorVect = entityForm.getFormErrors();

        try {
            int incompleteCount =
                ManualDAOFactory
                .getManualDocOrderDAO()
                .countInCompleteOrderUnit("REQUEST_ID");

            if (incompleteCount > 0) {
                errorVect.add(
                    "Please verify unassigned order units."
                );
                return false;
            }

        } catch (Exception e) {
            errorVect.add(e.getMessage());
            return false;
        }

        return super.validateResult();
    }
}
```

> For more advanced examples, refer to the Sample Apps validation documentation: <https://docs.oneweb.tech/oneweb/sample-apps/order-management-app-web/app-designer-customize/validate-order-details-when-back-office-submits>

***

#### Deploy Java Validation

1. Build and publish the project to the server.

From this point forward, ONEWEB will **automatically execute the Java validation** every time before the entity is saved.

***

### Summary

ONEWEB Smart Forms provide robust validation capabilities through both **client‑side** and **server‑side** mechanisms.

| Validation Type | Purpose                                              |
| --------------- | ---------------------------------------------------- |
| JavaScript      | Faster feedback, input format checks, UX improvement |
| Java            | Enforced business rules, data integrity, security    |

Using both approaches together ensures:

* Better user experience
* Strong data integrity
* Protection against invalid submissions
* Enterprise‑grade validation behavior

This layered validation model allows ONEWEB applications to scale safely while maintaining usability and correctness.


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