Access Java classes from Python
Go to file
dessant fc77dd624d Merge pull request #133 from chrisjrn/signatures
API for human-readable method signatures
2015-11-03 14:00:35 +02:00
docs pyjnius: document detach() function. Closes #97. Closes #107. 2015-02-07 20:07:56 +01:00
jnius Merge pull request #133 from chrisjrn/signatures 2015-11-03 14:00:35 +02:00
tests Merge pull request #133 from chrisjrn/signatures 2015-11-03 14:00:35 +02:00
.gitignore .gitignore: tighten ignore rules in jnius/ 2013-02-05 15:00:40 +05:30
.travis.yml change travis notification target 2015-07-28 12:07:36 +03:00
LICENSE update copyright year 2015-05-19 22:01:00 +03:00
MANIFEST.in ensure we raise the exception if cython is not installed on desktop 2012-08-21 01:19:43 +02:00
Makefile Fix issue #162 by making 'make tests' pass. 2015-04-30 19:36:56 -04:00
README.md doc: revisions to README.md 2014-03-07 14:57:30 +02:00
jnius_config.py Add control of JVM startup options 2014-05-09 18:20:29 +10:00
setup.py Use the java from java_home on OSX. 2015-05-03 11:30:30 -04:00

README.md

PyJNIus

A Python module to access Java classes as Python classes using JNI.

PyJNIus is a "Work In Progress".

Quick overview

>>> from jnius import autoclass
>>> autoclass('java.lang.System').out.println('Hello world')
Hello world

>>> Stack = autoclass('java.util.Stack')
>>> stack = Stack()
>>> stack.push('hello')
>>> stack.push('world')
>>> print stack.pop()
world
>>> print stack.pop()
hello

Usage on desktop

You need a java JDK installed (OpenJDK will do), Cython and make to build it.

make

That's it! You can run the tests using

make tests

to ensure everything is running correctly.

Usage with python-for-android

from time import sleep
from jnius import autoclass

Hardware = autoclass('org.renpy.android.Hardware')
print 'DPI is', Hardware.getDPI()

Hardware.accelerometerEnable(True)
for x in xrange(20):
    print Hardware.accelerometerReading()
    sleep(.1)

It will output something like:

I/python  ( 5983): Android kivy bootstrap done. __name__ is __main__
I/python  ( 5983): Run user program, change dir and execute main.py
I/python  ( 5983): DPI is 160
I/python  ( 5983): [0.0, 0.0, 0.0]
I/python  ( 5983): [-0.0095768067985773087, 9.3852710723876953, 2.2218191623687744]
I/python  ( 5983): [-0.0095768067985773087, 9.3948478698730469, 2.2218191623687744]
I/python  ( 5983): [-0.0095768067985773087, 9.3948478698730469, 2.2026655673980713]
I/python  ( 5983): [-0.028730420395731926, 9.4044246673583984, 2.2122423648834229]
I/python  ( 5983): [-0.019153613597154617, 9.3852710723876953, 2.2026655673980713]
I/python  ( 5983): [-0.028730420395731926, 9.3852710723876953, 2.2122423648834229]
I/python  ( 5983): [-0.0095768067985773087, 9.3852710723876953, 2.1835119724273682]
I/python  ( 5983): [-0.0095768067985773087, 9.3756942749023438, 2.1835119724273682]
I/python  ( 5983): [0.019153613597154617, 9.3948478698730469, 2.2122423648834229]
I/python  ( 5983): [0.038307227194309235, 9.3852710723876953, 2.2218191623687744]
I/python  ( 5983): [-0.028730420395731926, 9.3948478698730469, 2.2026655673980713]
I/python  ( 5983): [-0.028730420395731926, 9.3852710723876953, 2.2122423648834229]
I/python  ( 5983): [-0.038307227194309235, 9.3756942749023438, 2.2026655673980713]
I/python  ( 5983): [0.3926490843296051, 9.3086557388305664, 1.3311761617660522]
I/python  ( 5983): [-0.10534487664699554, 9.4331550598144531, 2.1068975925445557]
I/python  ( 5983): [0.26815059781074524, 9.3469638824462891, 2.3463177680969238]
I/python  ( 5983): [-0.1149216815829277, 9.3852710723876953, 2.31758713722229]
I/python  ( 5983): [-0.038307227194309235, 9.41400146484375, 1.8674772977828979]
I/python  ( 5983): [0.13407529890537262, 9.4235782623291016, 2.2026655673980713]

Advanced example

When you use autoclass, it will discover all the methods and fields of the object and resolve them. For now, it is better to declare and use only what you need. The previous example can be done manually as follows:

from time import sleep
from java import MetaJavaClass, JavaClass, JavaMethod, JavaStaticMethod

class Hardware(JavaClass):
    __metaclass__ = MetaJavaClass
    __javaclass__ = 'org/renpy/android/Hardware'
    vibrate = JavaStaticMethod('(D)V')
    accelerometerEnable = JavaStaticMethod('(Z)V')
    accelerometerReading = JavaStaticMethod('()[F')
    getDPI = JavaStaticMethod('()I')
    
# use that new class!
print 'DPI is', Hardware.getDPI()

Hardware.accelerometerEnable()
for x in xrange(20):
    print Hardware.accelerometerReading()
    sleep(.1)

Support/Discussion

mailto:pyjnius-dev@googlegroups.com