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# reflection

* Most frameworks are built on reflection (spring/jakarta)
* Android (dagger DI framework) and micronaut dont use reflection

## Links

* <http://www.java2s.com/Tutorials/Java/Java\\_Reflection/index.htm>
* <http://tutorials.jenkov.com/java-reflection/index.html>
* <https://www.javacodegeeks.com/2018/01/java-reflection-much-faster.html>
* <https://www.javatpoint.com/java-reflection>
* <https://www.youtube.com/watch?v=bhhMJSKNCQY> (coding with john intro)

## Drawbacks

* Don't use if you want low memory comsumption
* It is relatively slow
* Because there is no common reflection cache in Java, and reading reflective data is expensive, each library and framework produces a unique reflection cache. In a typical modern Java application, you will find Spring has a unique cache, Groovy has another cache, Jackson another, and so on. This makes it extremely difficult to optimize memory consumption.
* Reflective calls are much more difficult for the JIT to optimize. Efforts such as InvokeDynamic and others try to alleviate this situation, but reflective calls will never be as efficient.
*
* <https://softwareengineering.stackexchange.com/questions/101187/are-there-problems-with-using-reflection>
* <https://www.javacodegeeks.com/2022/06/reflection-means-hidden-coupling.html>