java调用python代码的两种实现方式:Runtime.exec()和Jython

# example.py
def add(a, b):
    return a + b

print(add(3, 5))

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class JavaCallPythonExample {
    public static void main(String[] args) {
        try {
            // 构建执行命令
            String[] cmd = {"python", "example.py"};

            // 执行命令
            Process process = Runtime.getRuntime().exec(cmd);

            // 读取输出流
            BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String line;
            while ((line = reader.readLine()) != null) {
                System.out.println(line);
            }

            // 关闭资源
            reader.close();

            // 等待进程完成
            int exitCode = process.waitFor();
            System.out.println("Process exited with code: " + exitCode);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

import org.python.util.PythonInterpreter;
import org.python.core.PyObject;

public class JavaCallPythonWithJython {
    public static void main(String[] args) {
        try (PythonInterpreter interpreter = new PythonInterpreter()) {
            // 执行 Python 代码
            interpreter.exec("def add(a, b): return a + b");

            // 调用 Python 函数
            PyObject result = interpreter.get("add", PyObject.class).__call__(3, 5);

            // 输出结果
            System.out.println(result.toString());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

mvn install:install-file \
  -Dfile=path/to/jython-standalone-X.Y.Z.jar \
  -DgroupId=org.python \
  -DartifactId=jython-standalone \
  -Dversion=X.Y.Z \
  -Dpackaging=jar

<dependencies>
  <!-- 其他依赖 -->
  <dependency>
    <groupId>org.python</groupId>
    <artifactId>jython-standalone</artifactId>
    <version>X.Y.Z</version>
  </dependency>
</dependencies>

<dependencies>
  <!-- 其他依赖 -->
  <dependency>
    <groupId>org.python</groupId>
    <artifactId>jython-standalone</artifactId>
    <version>2.7.2</version>
  </dependency>
</dependencies>

import org.python.util.PythonInterpreter;
import org.python.core.PyObject;

public class JavaCallPythonWithJython {
    public static void main(String[] args) {
        try (PythonInterpreter interpreter = new PythonInterpreter()) {
            // 执行 Python 代码
            interpreter.exec("def add(a, b): return a + b");

            // 调用 Python 函数
            PyObject result = interpreter.get("add", PyObject.class).__call__(3, 5);

            // 输出结果
            System.out.println(result.toString());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}