[yyyuutt]

I spent 10 years doing C# on a big system and love it. However it never got the momentum Java did so I've switched. I prefer C# over Java, I hate a lot of Spring attribute/factory/builder craziness, but Java has so much more wider support I would always choose it first now.

[spaetzleesser]

Same here. The Java ecosystem has almost everything you could ever imagine needing so it’s a safer bet. Maybe it’s not as shiny but it works. I don’t understand why MS doesn’t provide the ability to call Java code from .NET. It would open up a lot of libraries to the platform. Right now there are a lot of libraries that are first class in Java but have either no or only half baked .NET ports.

[topkai22]

Quite possibly the Sun-Microsoft lawsuit from 20 years ago, and the ongoing Oracle/Google drama.

[1] https://www.cnet.com/news/sun-microsoft-settle-java-suit/ [2] https://en.m.wikipedia.org/wiki/Oracle_America,_Inc._v._Goog....

[Nelkins]

There was some plan to beef up their Java Interop library (currently used with Xamarin on Android) for more general usage for .NET 5, but I think it fell by the wayside. It'll probably happen eventually though.

https://github.com/xamarin/java.interop

[fomine3]

Looks interesting that to be used outside Xamarin.

[cutler]

Which libraries? Could you give some examples?

[kinjba11]

Just off the top of my head, there are .NET copies of:

- Akka https://github.com/akka/akka - Lucene https://github.com/apache/lucene-solr - Aeron https://github.com/real-logic/aeron - Retrofit https://github.com/square/retrofit

Not to mention projects like Apache Spark, Cassandra, Elasticsearch, Druid - Java projects. Many projects (Foundation DB, Scylla DB, I could find more) will have in-house support for Java and not .NET.

The .NET equivalents to these libraries tend to be playing catch up. Xamarin Android will always be playing catch-up to Android's Java/Kotlin APIs for Android. Big machine learning projects like PyTorch and TensorFlow tend to give first-class support of some fashion to a Java API (mostly due to Android). Is there a .NET equivalent to Deeplearning4j? Hadoop? Hive? Kakfa?

In Java there is a proliferation of web projects: Spring, Vert.x, Quarkus, Micronaut, Play 2, Spark Java; Netty, Jetty, Apache. In .NET all you ever hear about is Microsoft projects ASP.NET core; Kestrel, IIS.

Working as a .NET dev, when there is an SDK, if it's not from Microsoft, it's clear the .NET SDK is a lower priority for bug fixes and new features compared to e.g. the Java/Python/etc.

[johnnycerberus]

Don't forget about the Java machine learning & deep learning "renaissance": Deeplearning4j https://deeplearning4j.org/, Konduit Serving https://serving.konduit.ai/, Amazon's open-source DJL https://djl.ai/ Apache Mahout https://mahout.apache.org/ Apache Arrow https://arrow.apache.org/

TensorFlow can run on any JVM for building, training and running machine learning models. They have created recently https://github.com/tensorflow/java

PyTorch also supports inference on the JVM but you still need to train with Python. https://www.infoq.com/news/2020/02/pytorch-releases-java-bin...

I think something like Scala will be used in the future instead of Python even for prototyping.

Streaming is also big business on the JVM: Apache Kafka https://kafka.apache.org/ (80% of Fortune 100 companies use it) Apache Flink https://flink.apache.org/ Apache Storm https://storm.apache.org/

Hard to think that .NET ecosystem will ever reach the ecosystem of Java when it comes to open-source.

[spaetzleesser]

Lucene, Bouncy Castle, a lot of niche research code is written in Java.