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Java Python without interpreter

So I was looking at various packages for for Java that allow you to run python code via Java. Jython does not handle the equivalent of python 3.6 code. So basically, I have code written in python 3.6 and requires so. I need to be able to utilize that python code via Java without having a python interpreter. Is there such a package? (Note I will not be changing the python code because that is a framework and that traditionally be used in python.
I have a python framework that would be traditionally utilized via python code of course, for python 3.6. Instead, I would like to be utilize it via Java 8 code. Now I looked into Jython but it does not handle 3.6 or 3.x for that matter. I will not be changing the python code from the framework. Additionally, the Java Package should be able to run the python code without an interpreter. Is there such a thing? Py4j requires a python interpreter.

GraalVM compiles Python code to Java bytecode and runs it on the JVM using graalpython, with this caveat:
This Python implementation currently aims to be compatible with Python 3.7, but it is a long way from there, and it is very likely that any Python program that requires any imports at all will hit something unsupported. At this point, the Python implementation is made available for experimentation and curious end-users.

No, running Python code requires some Python interpreter or other.

Since you won't change it, you could convert the Python to an executable and use Java to spawn it as a new process.
ProcessBuilder pb = new ProcessBuilder("C:\\...\\file.exe", command arguments, ..., ...);
pb.start();
You could use File I/O to communicate between Python and Java as the easiest solution.

how can we run python script(which uses nltk and scrapy) from java

I have written python scripts that use scrapy,nltk and simplejson in my project but i need to run them from java as my mentor wants to deploy them on a server and i have very less time to do this.I took a glance at runtime.exec() in java and jython, needless to say that running system commands from java doesn't look simple either.
So I would like to know if running the python scripts from java as system command -'python example.py ' using runtime.exec() or alternatively using jython would be more simpler and actually feasible or whether there is a simpler workaround .It would also be great to know if anyone had run python code that uses nltk from java using Jython and whether they encountered any problems.Please help me as I have to do this as asap.Any thoughts and suggestions regarding this are welcome.
Thanking in advance!!

The Jepp project lets you call python scripts from Java. It provides an easy mechanism to pass variables into a script and extract values back. I've used on a few projects with good success

Calling Java from Python

I have a Java app that takes a long time to be initialized (so I can't use a command-line like interface) and I need to pass text and receive the output of a Java method from Python. Is it possible to load the Java application, have it open all the time the Python script runs and use a method from that app?

I don't think the use of Python helps all that much over a command line (at least not a *nix command line), but the basic idea is to communicate over a socket or some similar mechanism. That means that the Java application will have to be wrapped in some code which opens a socket and waits for the python script to contact it. If you are most comfortable with python, you could look to implement that wrapper in Jython.

I've used JPype for something similar and it worked great.
JPype is an effort to allow python programs full access to java class libraries. This is achieved not through re-implementing Python, as Jython/JPython has done, but rather through interfacing at the native level in both Virtual Machines.
If the java app is running you should also consider xml-rpc as it also works well.

Py4J is a way to call Java from a python script. Here is the project website: http://py4j.sourceforge.net/

Using Python from within Java [duplicate]

This question already has answers here:
Closed 13 years ago.
Possible Duplicate:
Java Python Integration
I have a large existing codebase written in 100% Java, but I would like to use Python for some new sections of it. I need to do some text and language processing, and I'd much rather use Python and a library like NLTK to do this.
I'm aware of the Jython project, but it looks like this represents a way to use Java and its libraries from within Python, rather than the other way round - am I wrong about this?
If not, what would be the best method to interface between Java and Python, such that (ideally) I can call a method in Python and have the result returned to Java?

I'm aware of the Jython project, but
it looks like this represents a way to
use Java and its libraries from within
Python, rather than the other way
round - am I wrong about this?
Yes, you are wrong. You can either call a command line interpreter to run python code using Jyton or use python code from Java. In the past there was also a python-to-Java compiler, but it got discontinued with Jython 2.2

I would write a Python module to handle the text and language processing, and then build a small bridge in jython that your java program can interact with. The jython bridge will be a very simple one, that's really only responsible for forwarding calls to the python module, and return the answer from the python module to the java module. Jython is really easy to use, and setup shouldn't take you more than 15 minutes.
Best of luck!

I don't think you could use NLTK from Jython, since it depends on Numpy which isn't ported to the JVM. If you need NLTK or any other native CPython extension, you might consider using some IPC mechanism to communicate between CPython and the JVM. That being said, there is a project to allow calling CPython from Java, called Jepp:
http://jepp.sourceforge.net/
The reverse (calling Java code from CPython) is the goal of JPype and javaclass:
sourceforge.net/projects/jpype/
pypi.python.org/pypi/javaclass/0.1
I've never used any of these project, so I cant't vow for their quality.

Jython is a Python implementation running on the JVM. You can find information about embedding Python in an existing Java app in the user guide.
I don't know the environment that you're working in, but be aware that mixing languages in the same app can quickly lead to a mess. I recommend creating Java interfaces to represent the operations that you plan to use, along with separately-packaged implementation classes that wrap the Python code.

IN my opinion, Jython is exactly what you are looking at.
It is an implementation of Python within the JVM; as such, you can freely exchange objects and, for instance, inherit from a Java class (with some limitations).
Note that, its major strength point (being on top of of JVM) is also its major drawback, because it cannot use all (C)Python extension written in C (or in any other compiled language); this may have an impact on what you are willing to do with your text processing.
For more information about what is Jython, its potential and its limitations, I suggest you reading the Jython FAQ.

Simply run the Python interpreter as a subprocess from within Java.
Write your Python functionality as a proper script, which reads from stdin and writes to stdout.
Use the Java Runtime class to spawn a subprocess that runs your Python script. This is very simple to do and provides a very clean interface.
Edit
import simplejson
import sys
for request in sys.stdin.readlines():
args = simplejson.loads( request )
result = myFunction( args['this'], args['that'] )
sys.stdout.writeline( simplejson.dumps( result ) + "\n" )
The interface is simple, structured and very low overhead.

Remember to first check from those paying for the development that they're OK with the codebase needing a developer who knows both Python and Java from now on, and other cost and maintainability effects you've undoubtedly already accounted for.
See: http://www.acm.org/about/se-code 1.06, 2.03, 2.09, 4.03, 4.05, 6.07

How can I embed Lua in Java?

Is LuaJava a must for this? Or can I embed Lua into Java without it?

LuaJ is easy to embed in Java. I did have to change a few lines of their source to get it to work how I expected (it didn't require the IO library automatically).
http://sourceforge.net/projects/luaj/

Try also kahlua and Mochalua.

There is http://www.keplerproject.org/luajava/manual.html, but essentially lua is more suitable for integration with C. There are a bunch of other scripting languages with good java integration around though. Consider groovy, jruby or jython for starters.

Lua is a C library, you can embed it in Java but you'll have to interface the java virtual machine and Lua with some C code.
The LuaJava authors have already done that work - you're better off using that than writing your own.