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Comment by TedDoesntTalk | Hacker News Reader

> reams of docs and stackoverflow answers which will almost certainly contain solutions

This is both a blessing and a curse. Some answers and docs are decades old and although still work, are not “fashionable java” (think streams, for instance).

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This is why I gave up on Java years ago. There seemed to be a lot of cruft left in the language and libraries that you were just supposed to know to not use anymore. I guess for backwards compatibility, but as a learner it's rather frustrating.

Has that gotten better recently? It's been years since I've toyed with it.

A lot of cruft has been split into modules, so you no longer have AWT/Swing/smartcardio/etc. in your classpath unless you want it.

A lot of cruft is still there; Date, File, InputStream/OutputStream, sun.misc.Unsafe, and the entire legacy reflection API are the bunch that stick out to me. Newer releases are actively mentioning their legacy status in documentation, and there are certainly JEPs to remove them or make them opt-in/opt-out.

If you look at OpenJDK internals, or even the foreign function/memory APIs as described in the article, it looks almost nothing like the Java I learned on and wrote for several years. Most of the Panama API is piggybacking on additions to the language made post-JDK9 or so, such as MethodHandle, VarHandle and @PolymorphicSignature methods. So I'd say the language and runtime is evolving nicely, even under the thumb of Oracle.

> InputStream/OutputStream

I think I missed the announcement of those being "legacy" APIs? They show up all over the place including in libraries, what is the replacement?

The modern versions of these are Channel APIs in java.nio. The "N" in nio stands for "New" even though it was introduced in Java 1.4.

But the old ones aren’t superseded the same way Date is, though. You are perfectly fine using them and in fact will perform similarly well due to Loom (which has actually reimplemented them on top of async APIs)

>legacy reflection API

Did I miss something somewhere ? java.lang.reflect is still the standard way of doing Reflection.

You can use Method Handles now for better performance in a lot of cases

I occasionally have to touch Java though I'm far more at home in e.g. Python. If you don't mind, a consist mention off the top of your head of things that people in my position should know about, as we Google our Java issues. I'm not cutting and pasting Stack Overflow answers, but even so they often do form the basis of ideas of the code that I write in the end. So pitfalls and modern replacements for ancient practices would be appreciated. Thank you!

I’m new to Java so I just want to confirm… are you saying streams are or are not fashionable? Is there a better api out there?

No, there are pre-streams answers, but streams are now fashionable.

And streams are part of the reason checked exceptions are now unfashionable. Java doesn’t infer that a generic function arg should affect the caller’s exception signature.

Checked exceptions are the bane of my existence

What’s not fashionable about streams in Java? I’ve seen many modern open source Java projects using them.

Parent might mean it in the negative, that those answers won’t use streams.

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