Скачать или смотреть How to Serialize Request Object without Field Name in Spring Boot

Learn how to use `@ JsonAnySetter` in Kotlin with Spring Boot to customize the serialization of request objects without specific field names.
---
This video is based on the question https://stackoverflow.com/q/73674165/ asked by the user 'krown_loki' ( https://stackoverflow.com/u/10250453/ ) and on the answer https://stackoverflow.com/a/73692020/ provided by the user 'krown_loki' ( https://stackoverflow.com/u/10250453/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How to serialize request object without field name in Spring Boot?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Serialize Request Object without Field Name in Spring Boot

In the world of web development, particularly when dealing with REST APIs in Spring Boot, you may encounter scenarios where the default serialization of request objects does not meet your requirements. One such scenario is when you want to include additional properties in a request body without prefixing them with a specific field name. In this guide, we'll explore how to achieve this in Kotlin using the @ JsonAnySetter annotation.

The Problem

You might have a simple REST Controller method in Kotlin that uses the @ RequestBody annotation to accept an object. Here's an example structure:

[[See Video to Reveal this Text or Code Snippet]]

Where ExampleObject is defined as follows:

[[See Video to Reveal this Text or Code Snippet]]

With this setup, you'd expect to send a request body like this:

[[See Video to Reveal this Text or Code Snippet]]

However, you might want to simplify your request structure. Specifically, you want the ability to send data that looks like this:

[[See Video to Reveal this Text or Code Snippet]]

The Solution

To achieve this functionality in Spring Boot, you can utilize the @ JsonAnySetter annotation provided by the Jackson library. Below are the steps you need to follow to modify your ExampleObject.

Step 1: Modify ExampleObject

Change the ExampleObject class to include the @ JsonAnySetter annotation. Here’s how the modified class should look:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Explanation of Changes

Removing Map from Constructor: We remove the paramOne from the constructor. Instead, we define it within the class body.

Using @ JsonAnySetter: This annotation tells Jackson to take any additional properties in the JSON input that don’t have matching fields and send them to the specified method. In our case, the method setParamOne(key: String, value: Int) adds those properties to the paramOne map.

Step 3: Sending the Request

With these changes, you can now send the request body in the desired format:

[[See Video to Reveal this Text or Code Snippet]]

In this case, testStringOne and testStringTwo will automatically populate the paramOne map.

Conclusion

Using the @ JsonAnySetter annotation provides a clean solution for accepting dynamic JSON fields in your Spring Boot application without having to define specific properties for each expected field in the request. This approach not only simplifies your request body but also makes your API more flexible and easier to use.

If you have further queries about using Jackson with Spring Boot or need additional examples, feel free to reach out in the comments below!