I've .NET framework 3.5 installed in my laptop. Just .NET alone, no Visual Studio. How can I run Java, Python, Ruby and Perl programs from the console?
Do I need to install something else also, for running these language files?
In case there is a need for something extra to be installed and after i have all of them, what are the commands that I need to type in the console to run these programs?
Do you want to run programs in these languages inside the .NET platform? You'd need IronPython or IronRuby (I don't think anything like IronPerl exists).
If you want to run "normal" Python/Ruby/Perl/Java programs, then yes, you'll need to install a Python interpreter, a Ruby interpreter, a Perl interpreter and a Java VM.
Perl is a bit of a problem, see this SO question. IronRuby and IronPython cover those two languages. For Java, I think you need Microsoft's J# (but I'm not entirely clear on the "visual vs not" situation for that product).
None of those languages are supported natively with .NET. You can try IronPython or IronRuby for those languages, but to run Java or Perl I think you'll actually need to download and install a Java VM and a perl interpreter.
There's no practical common virtual machine or binary for the options you list. You will require a separate install for each of these (note that all are unrelated to .NET)
Related
I wonder if it is possible to use GraalPython as a Java library to interpret Python code on a standard JVM. If so, would it be a good choice to replace Jython (which only supports Python 2.7)?
Is this possible without importing the entire GraalVM project? I expect only Truffle and the Python interpreter built on top of it should be necessary.
If this is not possible, are there any good Java implementations of Python 3 available?
You should be able to run any GraalVM language on any JDK as their are just Java programs. However, the performance will be affected a lot. Moreover, languages like python consist of additional resources (standard library files, etc.) that you would have pull from GraalVM too.
This document about GraalVM JavaScript discusses this in more detail and describes how to run GraalVM JavaScript on stock JDK without compromising the performance. Some of it can be applicable to GraalPython.
https://github.com/graalvm/graaljs/blob/master/docs/user/RunOnJDK.md
Tl;dr: it will be much easier to use GraalVM. It's full JDK distribution. You are not missing on anything. If you can't, there are some ways.
Can Python invoke the Java Framework?
I want to know whether a Python project can invoke a Java Framework, I find a Java Framework in GitHub, whether I can use it in my Python project?
Jython
Jython is one method of calling Java from python -- actually, you run your Python inside Java JVM. This gives you access to almost any Java that runs on JVM, but comes with many limitations.
Because Jython is running python inside the JVM, this gives you acess to almost any Java library. However, you are very restricted in what Python you can use: you can only use Python 2.7, and can import pure Python libraries only (compiled Python libraries with C will not run on Jython).
For an example of a project that uses Jython: Processing.py runs on Jython in order to access the Processing Java API and its ecosystem of Java libraries.
https://github.com/jdf/processing.py
Note that Jython 2 and its docs are quite old, and that the developers are uncertain if / when Jython 3 will be released.
https://github.com/jython/jython3
py4j
py4j is a different approach -- it is "A Bridge between Python and Java" and lets native python code access separate Java running in a separate JVM. Note however that the python and Java code must be running in parallel and communicating through a gateway interface. This is communication between separately running processes -- you are not spinning up a JVM from Python or inside Python.
For example: on the JVM side pass myObject to a new GatewayServer(myObject); on the Python side create a JavaGateway() Python object and use it to communicate with the Java myObject.
Normally Python and Java have their own interpreters/VM's and cannot be shared. It is possible to use Jython but has limitations (fe. python version and support/compatibility with other python packages).
The interpreter and JVM do not match: Java has strict typing, python not. Java compiles and run, python is an interpreter and can change code in runtime (if you want). These are extra challenges why putting all in a same environment is very complex.
There are possibilities like a client/server architecture, but the feasability depends on the level of the framework.
Most of the time low level frameworks are optimized to run directly inside your application process. Any loose coupling will introduce performance and security and compatibility issues. Just think about how reflection will work or multiple inheritance.
If it is a high level framework (fe able to run stand alone) it is more feasable to use some sort of client/server. But still you have to develop a lot for it.
Industry standard is just to implement the framework of your desire in the language you want, then you can get also all the benefits of your platform.
ok, So i searched net for the possible implementation but all that I managed to find is Django projects implementation on Java platform through Jython. But I want to do the reverse, i.e. implement/integrate java project ( which in my case is SAIKU server ) on Django platform.
The question being, is it possible, and if yes, then kindly point me to the solution.
Thanking in advance =)
For your specific requirement, I would suggest using RESTFul API to access the Saiku Server.
However if you need to run Java Classes from Python.
Here are the options available for you:
JCC -- a C++ code generator for calling Java from C++/Python. It produces producing Python extensions which communicate via JNI with a Java virtual machine. As it implies, this would require compilations of every possible call. However this project is backbone of PyLucene project.
CodeMesh. C++ code generator for Java.
Py4J Python programs running in a Python interpreter to dynamically access Java objects in a Java Virtual Machine.
JPype allow python programs full access to java class libraries. It is done through interfacing at the native level in both Virtual Machines. However there are no recent development in this front.
In general, having an loosly coupled integration through REST or RCP would be easy to maintain than tightly coupled JNI based implementation.
There's no way to run Java within the Python runtime (which is what it sounds like you want). There are Java to Python "translators" available, but they're terrible. Honestly, if you need a Java server and Django to sit inside the same process for some reason, Jython is the way to go.
There are lots of options outside of that though, off the top of my head:
Implement Python bindings for your server (See PyLucene for an example)
Implement a socket server within your Java server that Python can talk to directly
I have several scripts written in perl, python, and java (wrapped under java GUI with system calls to perl & python). And I have many not-tech-savy users that need to use this in their windows machines (xp & 7).
To avoid users from installing perl,python,and java and to avoid potential incompatibility between various versions of these interpreters, I'd like to make a local copy of these interpreters in a folder and then calling them. I'd zip the whole folder (which would also contain my code) and send it away.
I'd have to worry about environment variables and make calls to the correct interpreter (especially when other versions of python,java,perl may exists in their current system), but not sure what other problems I may face. Any better ideas?
I never used jython and do not know the overhead of moving to it. I also suspect a complex python system, with many files and 3rd party modules will have problems. Same with perl scripts and I don't know a robust perl interpreter callable from java.
Thank you, in advance.
Try Portable Python and Portable Perl. You can unzip them into your application tree and they should work.
Why don't you try migrating your perl/python code into java and then packagin everything into a nice webstart application? What do perl/python offer that java doesn't support?
For perl you can use something like perl2exe and for python py2exe so you can have 2 exes (which would include all the necessary interpreter bits) and invoke them as resources from within java? Or unzip them inside user's home directory and call them again as normal external programs (ProcessBuilder ?) ?
I have to deploy some Web Services on a server that only supports the Java ones, but some of them will be done using perl or python. I want to know if is possible to develop a Java wrapper to call a specific code written in perl or python. So, I want to have all the Web Services in Java, but some of them will call some code using other languages.
Thanks in advance.
Regards,
Ukrania
This depends heavily upon your needs. If Jython is an option for the Python code (it isn't always 100% compatible), then it is probably the best option there. Otherwise, you will need to use Java's Process Builder to call the interpretters directly and return the results on their output stream. This will not be fast (but then again, Jython isn't that fast either, relative to regular Java code), but it is an extremely flexible solution.
For the Python part of it you can use Jython to run Python code right from your Java virtual machine. It'll integrate fully with your Java code as a bonus.
For Perl, use Inline::Java. There are several options for integrating the code; you can call a separate process or you can use an embedded interpreter.
For Python you can use the Java Scripting API.
A Perl implementation is sadly still missing.
There's something I used a while back called Jython which allows you to execute Python code from Java. It was a little quirky, but I got it to do what I needed.
http://www.jython.org