How do I include the field name by default in Jakarta validation messages?

One of the most frustrating things about validation messages is when they’re so generic they don’t even tell you what field is causing the problem. You know, those messages that say “Invalid value” or “Not valid” without giving you a single clue about what needs fixing. Ugh!

But fear not, dear developer! Jakarta validation messages don’t have to be that way. With a few simple tweaks, you can include the field name by default in your validation messages, making it crystal clear to your users what needs to be corrected.

Why include the field name, you ask?

Good question! Including the field name in validation messages has several benefits:

• Improved user experience: When users know exactly what field is causing the problem, they can fix it quickly and easily.
• Reduced frustration: No more guessing games or digging through the entire form to find the offending field.
• Increased accessibility: Screen readers and other assistive technologies can pick up on the field name, making it easier for users with disabilities to navigate.

The default Jakarta validation behavior

By default, Jakarta validation messages don’t include the field name. This means that when a validation error occurs, the message will be something like “must not be null” or “size must be between 3 and 50”. Not very helpful, right?

@example
Invalid value

How to include the field name by default

Luckily, Jakarta provides a simple way to include the field name in validation messages. All you need to do is:

1. Define a custom validation message interpolation
2. Set the {{validatedValue) placeholder in your validation messages
3. Use the messageInterpolator property in your persistence.xml file

1. Define a custom validation message interpolation

In your persistence.xml file, add the following configuration:

<persistence-unit name="myPU">
    <property name="javax.persistence.validation.message.interpolator" value="org.hibernate.validator.internal.engine.messageinterpolation.ResourceBundleMessageInterpolator"/>
</persistence-unit>

This tells Jakarta to use the ResourceBundleMessageInterpolator to interpolate validation messages.

2. Set the {{ validatedValue }} placeholder in your validation messages

In your ValidationMessages.properties file (or whatever file you’re using to store your validation messages), add the following messages:

javax.validation.constraints.NotNull.message = {0} must not be null
javax.validation.constraints.Size.message = {0} must be between {min} and {max} characters

Note the {0} placeholder, which will be replaced with the field name.

3. Use the messageInterpolator property in your persistence.xml file

Update your persistence.xml file to include the following property:

<persistence-unit name="myPU">
    <property name="javax.persistence.validation.message.interpolator" 
               value="org.hibernate.validator.internal.engine.messageinterpolation.ParameterMessageInterpolator"/>
</persistence-unit>

This tells Jakarta to use the ParameterMessageInterpolator to interpolate validation messages, which will include the field name.

Putting it all together

Now, when a validation error occurs, the message will include the field name, like this:

@example
username must not be null

Or, for size constraints:

@example
password must be between 8 and 50 characters

Much better, right?

Other ways to customize Jakarta validation messages

In addition to including the field name, you can customize Jakarta validation messages in other ways, such as:

• Using custom message keys: Instead of using the default message keys (e.g. javax.validation.constraints.NotNull.message), you can define your own custom message keys.
• Providing additional information: You can include additional information in your validation messages, such as the expected format or range of values.
• Using message bundles: You can store your validation messages in a message bundle, which can be easily translated or replaced.

Conclusion

Including the field name by default in Jakarta validation messages is a simple but powerful way to improve the user experience and reduce frustration. By following these steps, you can provide clear and informative validation messages that help your users correct their mistakes quickly and easily.

Remember, validation messages don’t have to be generic and unhelpful. With Jakarta, you have the power to customize your messages and create a more user-friendly experience.

Related articles
How to customize Jakarta validation messages
Jakarta validation: A comprehensive guide
Best practices for writing effective validation messages

Want to learn more about Jakarta validation and how to create amazing user experiences? Check out our related articles and tutorials!

Frequently Asked Question

Get ready to conquer the world of Jakarta validation messages!