Getting Started with Jython: Integrating Python and Java

Jython is an implementation of the Python language on the Java platform, allowing developers to run Python code within a Java environment and seamlessly access Java class libraries.

Features : direct Java library calls, cross‑platform execution, and preservation of Python’s dynamic characteristics.

Installation : download the installer from the official Jython website, run the installer, and add the Jython installation directory to the system PATH.

Running Jython :

Command‑line interactive session:

$ jython
Jython 2.7.3 (default:183f3888753e, Mar 17 2021, 10:54:12)
[OpenJDK 64‑Bit Server VM (Oracle Corporation)] on java11.0.10
type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello, Jython!")

Running a script file (e.g., hello.py ) with jython hello.py .

Using Java classes from Jython :

from java.util import ArrayList
# 创建一个ArrayList对象
list = ArrayList()
# 添加元素
list.add("apple")
list.add("banana")
# 遍历列表
for item in list:
    print(item)

Calling Jython from Java :

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
public class RunJythonScript {
    public static void main(String[] args) {
        try {
            // 创建脚本引擎管理器
            ScriptEngineManager manager = new ScriptEngineManager();
            // 获取Jython脚本引擎
            ScriptEngine engine = manager.getEngineByName("jython");
            // 执行Jython脚本
            engine.eval("print('Hello, from Java calling Jython!')");
        } catch (ScriptException e) {
            e.printStackTrace();
        }
    }
}

Application scenarios include scripting within large Java projects (e.g., data preprocessing), rapid prototyping by leveraging Python’s concise syntax, and writing flexible automated test scripts that combine Java testing frameworks with Python’s ease of use.

Conclusion : Jython bridges Python and Java, combining the strengths of both languages and enabling developers to choose the most suitable tool for various programming tasks.