This document discusses integrating Java with Python by: 1) Allowing seamless interaction between the two languages during development and in shipping products using tools like Jython. 2) Jython allows running Python on the Java Virtual Machine (JVM) enabling Python scripts to use Java frameworks. 3) Communicating between Java and Python apps can be one-directional, from Python apps to Java apps by sending JSON formatted text messages.

1. NADAR SARASWATHI COLLEGE
OF ARTS & SCIENCE
INTEGRATING JAVA WITH
PYTHON
DEPARTMENT OF COMPUTER SCIENCE
PRESENTED BY B.ARCHANA
I- M SC (CS)

2. INTEGRATE JAVA WITH PYTHON
•
• THE SEAMLESS INTERACTION BETWEEN PYTHON AND JAVA ALLOWS
DEVELOPERS TO FREELY MIX THE TWO LANGUAGES BOTH DURING
DEVELOPMENT AND IN SHIPPING PRODUCTS

3. HOW TO USE JAVA WITH PYTHON
•
• JYTHON IS THE JAVA PLATFORM IMPLEMENTATION OF PYTHON
WHICH RUNS ON THE JVM. ASSUMING THAT WE HAVE JYTHON ON
THE CLASSPATH, THE FRAMEWORK SHOULD AUTOMATICALLY
DISCOVER THAT WE HAVE THE POSSIBILITY OF USING THIS
SCRIPTING ENGINE AND ENABLE US TO ASK FOR THE PYTHON
SCRIPT ENGINE DIRECTLY.

4. COMMUNICATE BETWEEN JAVA AND PYTHON
• THE COMMUNICATION IS ONE DIRECTION: FROM PYTHON APP TO JAVA APP.
EVERY MESSAGE IS ONE LINE OF TEXT (ULTIMATELY: JSON FORMAT). E.G.:
“TEXTRN”. TO CLOSE COMMUNICATION, WE SEND MESSAGE: “XRN”

5. A SIMPLE PYTHON SCRIPT
• THROUGHOUT THIS TUTORIAL, WE’LL USE A VERY SIMPLE PYTHON SCRIPT
WHICH WE’LL DEFINE IN A DEDICATED FILE CALLED HELLO.PY;
• PRINT(“HELLO BAELDUNG READERS!!”)
python hello.py Hello Baeldung Readers!!

6. •
•
• FROM PY4J.JAVA_GATEWAY IMPORT JAVAGATEWAY
•
• GATEWAY = JAVAGATEWAY()
•
• MSGOBJECTFROMJAVAAPP = GATEWAY.ENTRY_POINT
• PRINT(MSGOBJECTFROMJAVAAPP.MESSAGE())

7. BEST USE JAVA AND JPYTHON TOGETHER
• JYTHON – PYTHON IMPLEMENTED IN JAVA
• JPYPE – ALLOWS PYTHON TO RUN JAVA COMMANDS
• JEPP – JAVA EMBEDDED PYTHON
• JCC – A C++ CODE GENERATOR FOR CALLING JAVA FROM C++/PYTHON
• JAVABRIDGE – A PACKAGE FOR RUNNING AND INTERACTING WITH THE JVM FROM
CPYTHON
• PY4J – ALLOWS PYTHON TO RUN JAVA COMMANDS.
• VOC – PART OF BEEWARE SUITE. CONVERTS PYTHON CODE TO JAVA BYTECODE.
• P2J – CONVERTS PYTHON CODE TO JAVA. NO LONGER DEVELOPED.

8. HOW TO RUN PYTHON SCRIPT WITH
ARGUMENTS FROM JAVA
•
• YOU CAN USE JAVA RUNTIME. EXEC() TO RUN PYTHON SCRIPT, AS AN EXAMPLE
FIRST CREATE A PYTHON SCRIPT FILE USING SHEBANG AND THEN SET IT
EXECUTABLE.

9. PASS COMMAND LINE ARGUMENTS IN ECLIPSE
• STEP 1: OPEN THE CLASS RUN CONFIGURATIONS SETTINGS. FROM THE CLASS
EDITOR, RIGHT CLICK AND CHOSE “RUN AS” -> “RUN CONFIGURATIONS…”. …
• STEP 2: SPECIFY THE PROGRAM ARGUMENTS IN THE ARGUMENTS TAB. IN THE
POP UP WINDOW, CLICK ON THE ARGUMENTS TAB. …
• STEP 3: CLICK ON THE RUN BUTTON.

10. THANK YOU