How to Run A Python Function In Kotlin?

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To run a Python function in Kotlin, you need to establish an inter-operational bridge between the two languages. Here's a step-by-step guide on how to do it:

  1. Install the Python Interpreter: Before using Python in Kotlin, you need Python installed on your system. Install Python from the official website ( if you haven't already.
  2. Configure the Kotlin Project: Set up a new Kotlin project in your preferred Integrated Development Environment (IDE) or use an existing project.
  3. Add the Jython Library: Jython is a Java implementation of Python that enables Python code execution within a Java Virtual Machine (JVM). You need to add the Jython library to your Kotlin project. Download the Jython JAR file from the official website ( and include it in your project's dependencies.
  4. Import the Required Packages: In your Kotlin code, import the necessary Jython packages to use Python functionality. Typically, you need to include these imports:
    import org.python.util.PythonInterpreter
    import org.python.core.PyObject
    import org.python.core.PyString

  1. Create a PythonInterpreter Object: Instantiate a PythonInterpreter object within your Kotlin code. This object will execute Python code in Kotlin.
    val pythonInterpreter = PythonInterpreter()

  1. Call the Python Function: To call a Python function, use the PythonInterpreter object and pass the necessary Python code. For example:
    pythonInterpreter.exec("def greet():\n\tprint('Hello from Python!')\ngreet()")

Here, we define a Python function called "greet" that prints a message, and then we call that function.

  1. Access Python Function's Return Value: If your Python function returns a value, you can access it in Kotlin. For instance:
    val returnValue: PyObject = pythonInterpreter.eval("10 + 20")

In this case, we retrieve the return value of a Python expression that calculates the sum of two numbers.

  1. Clean Up the PythonInterpreter: After you finish using the PythonInterpreter, it is good practice to properly clean it up to release any resources. Invoke the close() method on the PythonInterpreter object:

Remember that integrating Python and Kotlin using Jython implies some performance overhead compared to running pure Kotlin or pure Python code. However, it facilitates the execution of Python functions in Kotlin projects.

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What is the use of running a Python function in a Kotlin project?

Running a Python function in a Kotlin project can have several use cases:

  1. Utilize existing Python libraries: Python has a rich ecosystem of libraries in various domains such as data science, machine learning, natural language processing, etc. Running a Python function in a Kotlin project allows you to leverage these Python libraries and their functionalities within your Kotlin codebase.
  2. Interoperability between languages: When working on a project that requires functionalities from both Python and Kotlin, running a Python function within a Kotlin project enables seamless communication and sharing of data between the two languages. This can be useful in cases where different team members or teams are proficient in different languages.
  3. Integration with legacy code or systems: In some scenarios, legacy code or systems might be written in Python. By running Python functions within a Kotlin project, you can integrate and interact with the legacy code or systems without having to fully rewrite or migrate them to Kotlin.
  4. Rapid prototyping: Python is known for its ease of use and quick prototyping capabilities. By running a Python function within a Kotlin project, you can use Python's agility to develop and test certain functionalities rapidly, while still maintaining the overall structure and logic of the Kotlin project.

Overall, running a Python function in a Kotlin project allows you to take advantage of the strengths and capabilities of both languages, enabling you to build more powerful and versatile applications.

How to integrate Python libraries in Kotlin?

To integrate Python libraries in Kotlin, you can use the Python interpreter provided by the Jython project, which allows you to run Python code directly in Java applications. Here's how you can do it:

  1. Add the Jython dependency to your Kotlin project. You can do this by adding the following line to your Gradle build file: implementation 'org.python:jython-standalone:2.7.2' This will download the Jython library and make it available in your project.
  2. Create a Python script that uses the desired Python libraries. Save the script as a .py file in your project directory.
  3. In your Kotlin code, import the necessary Jython classes: import org.python.core.PyObject import org.python.util.PythonInterpreter
  4. Create a PythonInterpreter object: val interp = PythonInterpreter()
  5. Execute the Python script using the interpreter: interp.exec("execfile('path/to/your/')") Replace 'path/to/your/' with the actual path to your Python script.
  6. Access the Python libraries and functions in Kotlin by retrieving the Python objects from the interpreter: val somePythonObject = interp.get("somePythonObject", Replace 'somePythonObject' with the name of the Python object you want to access.
  7. Use the Python object in your Kotlin code by calling its methods or accessing its attributes: val result = somePythonObject.__call__(arg1, arg2) Replace arg1 and arg2 with the appropriate arguments for the Python function.

Remember to handle any exceptions that may be thrown during the execution of the Python code.

Please note that Jython has limitations and may not be compatible with all Python libraries, especially those that have C-based dependencies. In such cases, you may need to explore other alternatives like using Python via command line or calling Python scripts as separate processes.

How to overcome compatibility issues while running Python functions in Kotlin?

To overcome compatibility issues while running Python functions in Kotlin, you can follow these steps:

  1. Choose a method of invoking Python code from Kotlin: There are different options for invoking Python code from Kotlin such as using the Python subprocess module, Py4J library, or Jython.
  2. Install dependencies: Ensure that you have the necessary dependencies installed for invoking Python code in Kotlin. For example, if you are using Py4J, you will need to install the Py4J library in your Kotlin project.
  3. Define Python functions or scripts: Write the required Python code or functions that you want to use in Kotlin. Make sure that the Python code is compatible with the version of Python you are using.
  4. Invoke Python functions from Kotlin: Use the chosen method of invoking Python code to call the Python functions from Kotlin. Pass the necessary arguments and handle the returned values accordingly.
  5. Handle data conversion: If you are passing data between Python and Kotlin, you might need to handle data conversion as per the data types and formats used in both languages. Py4J provides convenient ways to handle conversions between Python and Java/Kotlin types.
  6. Error handling: Handle any exceptions or errors that may arise during the interaction between Python and Kotlin. Ensure that you have proper error handling mechanisms in place to identify and address any compatibility issues.
  7. Test and debug: Thoroughly test your Kotlin code that interacts with Python functions to identify and fix any compatibility issues. Debugging tools specific to Kotlin and Python can be used as needed.

Remember to consider the compatibility of libraries and modules used in both Python and Kotlin ecosystems. Additionally, it's important to stay updated with the latest versions and documentation of the libraries being used for invoking Python functions in Kotlin.

What is the difference between Kotlin and Python programming languages?

Kotlin and Python are two programming languages that have different features and use cases.

  1. Syntax: Kotlin has a statically-typed syntax that is similar to languages like Java, making it easy for Java developers to pick up. On the other hand, Python uses dynamic typing and has a simple and clean syntax, which is designed to be easily readable and expressive.
  2. Purpose: Kotlin is primarily used for developing Android applications. It is a modern language that offers a lot of features, such as null safety, extension functions, coroutines, etc., making it ideal for building robust and efficient Android apps. Python, on the other hand, is a general-purpose language that is widely used in various domains, including web development, data analysis, artificial intelligence, scripting, and automation.
  3. Performance: Kotlin is compiled to bytecode and runs on the Java Virtual Machine (JVM), which provides good runtime performance. Python, on the other hand, is an interpreted language, which generally makes it slower than compiled languages. However, Python offers various libraries and frameworks written in lower-level languages (like C), which allows for high-performance computing when needed.
  4. Ecosystem and Libraries: Kotlin has a growing ecosystem, with good integration with existing Java libraries, frameworks, and tools. It also has its own set of libraries and frameworks specifically designed for Android development. Python has a vast and mature ecosystem with a wide range of libraries and frameworks available for different purposes, making it highly versatile and efficient for many applications.
  5. Community and Popularity: Python has gained immense popularity over the years due to its simplicity, readability, and versatility, and has a large community of developers actively contributing to its growth. Kotlin, though relatively new, has been widely adopted by Android developers and has been increasingly gaining popularity due to its modern features and seamless integration with existing Android projects.

Overall, the choice between Kotlin and Python depends on the specific requirements of a project and the domain it is being developed for.

How to handle exceptions when running a Python function in Kotlin?

When running a Python function in Kotlin, you can handle exceptions using try-catch blocks. Here's an example of how you can handle exceptions in Kotlin when calling a Python function:

  1. Import the necessary packages:
import java.lang.Exception
import java.lang.Runtime.getRuntime

  1. Create a function to run the Python script with error handling:
fun runPythonScript() {
    try {
        // Execute the Python script using process builder
        val process = getRuntime().exec("python")
        // Get the output/error streams
        val outputStream = process.getInputStream()
        val errorStream = process.getErrorStream()

        // Read the output/error of the Python script
        val output = String(outputStream.readBytes())
        val error = String(errorStream.readBytes())

        // Handle output and error accordingly
        if (output.isNotEmpty()) {
            // Process the output

        if (error.isNotEmpty()) {
            // Handle the error
        // Wait for the Python script execution to complete
        // Clean up resources
    } catch (e: Exception) {
        // Handle any exceptions that occurred during execution

This example uses ProcessBuilder to execute the Python script and retrieves the output and error streams. It then reads and processes the output and error accordingly. If any exceptions occur during execution, they will be caught and printed using printStackTrace().

Note: Make sure you replace "python" with the appropriate Python script path/name that you want to execute.

By handling exceptions in the catch block, you can provide appropriate error handling or fallback actions, ensuring your Kotlin code gracefully handles any unexpected issues that may occur while running the Python function.

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