javawriter VS Jackson JSON Processor

javapoet (for generating code in Java): square/javapoet: A Java API for generating .java source files. (github.com)

Resources: 1. Spring Boot Official Documentation on configuring multiple data sources: Spring Boot Reference Documentation 2. javapoet (for generating code in Java): square/javapoet: A Java API for generating .java source files. (github.com) 3. Guide to Annotation Processing in Java: Java Annotation Processing and Creating a Builder | Baeldung

Javapoet. This helped me a lot, because i wrote two generators, one for one employer, who don't like dynamic generators, so the first was to generate mappers like mapstruct does; from model to pojos and viceversa. The second one was a static testing pojo factory generator; this last one i made public (it's pretty basic and now we have projects like instancio and podam) its name is mother-factory.

> can you show an example of how you'd parse, say, a .java.in

The canonical way to do such a thing is through the java annotation processing api [1] and using a tool like java poet [2]. Before you did that, you'd probably decide if you wanted to instead use bytecode generation with a library like bytebuddy [3]

But, assuming for some reason, you wanted to torture yourself and actually consume a java.in file and apply a regex, then you'd probably pull out the "maven-replacer-plugin" [4] and configure that for the task at hand. (or use your favorite templating language plugin. There's a million of them).

Though, to be fair, this really isn't something that comes up in regular java programming due to the nature of the ecosystem. Anything you'd want to codegen likely already has a library and anything you didn't would receive (legitimate) push back.

[1] https://www.baeldung.com/java-annotation-processing-builder

[2] https://github.com/square/javapoet

[3] https://bytebuddy.net/

[4] https://github.com/beiliubei/maven-replacer-plugin

I’ve used a maven archetype before with velocitemplate. That solution was iffy so we then migrated to using https://github.com/square/javapoet to generate the java source and write it to the desired files. I think we also used the google formatter library so the files would be formatted after generating.

JavaPoet

We can then easily convert this string value into the array of Products using librares like Jackson.

The above class maps the json data to a java object we can work with. We use Lombok to generate constructors, getters and setters for our code and the Jackson Project to handle serialization and deserialization of json to pojo . We know the response is an array of objects representing the coffee and so above data structure is fit for this.

Jackson. Because JSON.

For my series of articles, I also wanted to see how this requirement to mapping values could be implemented with Jackson.

In practical terms, Jackson achieves the same purpose for Java. It was born as a Json parser, but nowadays supports multiple formats and it's widely used in the Java community.

How can Jackson library help you out?

jackson

Jackson para lidar com JSON;

An example of a Snowflake API request using Java. This example uses Java’s built-in HttpClient and constructs JSON manually, so it doesn’t require additional dependencies; however, in production, you should use a library like Jackson for constructing JSON. Additionally, for stronger typing, you could use Apollo’s Kotlin-based GraphQL client.