Add new java printer

[stephweissm]

References to other Issues or PRs

Brief description of what is fixed or changed

JavaScript looks supported. But there is no printer for Java.

Other comments

Release Notes

• printing
  • Code printer for Java

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• printing
  • Code printer for Java (#26522 by @stephweissm)

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#### Brief description of what is fixed or changed
JavaScript looks supported. But there is no printer for Java.

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#### Release Notes

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* printing
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[sympy-bot]

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Hi, I am the SymPy bot. I've noticed that some of your commits add or delete files. Since this is sometimes done unintentionally, I wanted to alert you about it.

This is an experimental feature of SymPy Bot. If you have any feedback on it, please comment at sympy/sympy-bot#75.

The following commits add new files:

• 04e23cf:
  • sympy/printing/java.py
• 2f27c1b:
  • sympy/printing/tests/test_java.py

If these files were added/deleted on purpose, you can ignore this message.

[asmeurer]

Is this the only thing they have in common or is there more coming? It doesn't seem worth having a shard superclass for just one method.

[sylee957]

Generally, Java and Javascript is not very common, shares nothing common in history, and maintained by different entities (Oracle and W3C),
and does not share much things in common, so it may not be a good idea to create superclass printers.

I think that you need to add comprehensive test cases. It's hard to believe that it can generate generally correct code for Java, unless we can read the outputs.

[bjodah]

I think it is wise to reuse the names of the math functions (which are the same between Javascript and Java I believe). It does not need to use a subclass (and it doesn't look like it's an abstract one? so that would need to be renamed anyhow).

And yes, I think more tests are needed. Did you try to get the tests in test_algorithms to pass? (the choice of supported math functions lead me to believe that):

sympy/sympy/codegen/tests/test_algorithms.py

Line 136 in ab88a7d

def test_newtons_method_function__rtol_cse_nan():

If so, it would be great if we could test a full java compilation & execution on the CI-server (we already do this for C).
I see that some math functions are still missing, perhaps we should add those too? log1p comes to mind.

We could duplicate the _print_Pow method, but I would be curious to see if we could even move that into codeprinter.py instead, and rely on e.g. _print_Cbrt returning NotImplemented (but I think that should be a separate PR later in that case).