PyJNIus ======= A Python module to access Java classes as Python classes using the Java Native Interface (JNI). Warning: the pypi name is now `pyjnius` instead of `jnius`. [![Tests](https://github.com/kivy/pyjnius/workflows/Continuous%20Integration/badge.svg)](https://github.com//kivy/pyjnius/actions) [![Builds](https://github.com/kivy/pyjnius/workflows/Continuous%20Delivery/badge.svg)](https://github.com//kivy/pyjnius/actions) [![PyPI](https://img.shields.io/pypi/v/pyjnius.svg)]() [![Backers on Open Collective](https://opencollective.com/kivy/backers/badge.svg)](#backers) [![Sponsors on Open Collective](https://opencollective.com/kivy/sponsors/badge.svg)](#sponsors) Installation ------------ ``` pip install pyjnius ``` Quick overview -------------- ```python >>> 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 with python-for-android ----------------------------- * Get [http://github.com/kivy/python-for-android]() * Compile a distribution with kivy (PyJNIus will be automatically added) Then, you can do this kind of things: ```python 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 class and resolve them. You may want to declare and use only what you need. The previous example can be done manually as follows: ```python from time import sleep from jnius 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) ``` You can use the `signatures` method of `JavaMethod` and `JavaMultipleMethod`, to inspect the discovered signatures of a method of an object ```python >>> String = autoclass('java.lang.String') >>> dir(String) ['CASE_INSENSITIVE_ORDER', '__class__', '__cls_storage', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__javaclass__', '__javaconstructor__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__pyx_vtable__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__setstate__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'charAt', 'checkBounds', 'clone', 'codePointAt', 'codePointBefore', 'codePointCount', 'compareTo', 'compareToIgnoreCase', 'concat', 'contains', 'contentEquals', 'copyValueOf', 'empty', 'endsWith', 'equals', 'equalsIgnoreCase', 'finalize', 'format', 'getBytes', 'getChars', 'getClass', 'hashCode', 'indexOf', 'indexOfSupplementary', 'intern', 'isEmpty', 'join', 'lastIndexOf', 'lastIndexOfSupplementary', 'length', 'matches', 'nonSyncContentEquals', 'notify', 'notifyAll', 'offsetByCodePoints', 'regionMatches', 'registerNatives', 'replace', 'replaceAll', 'replaceFirst', 'split', 'startsWith', 'subSequence', 'substring', 'toCharArray', 'toLowerCase', 'toString', 'toUpperCase', 'trim', 'valueOf', 'wait'] >>> String.format.signatures() [(['java/util/Locale', 'java/lang/String', 'java/lang/Object...'], 'java/lang/String'), (['java/lang/String', 'java/lang/Object...'], 'java/lang/String')] ``` Each pair contains the list of accepted arguments types, and the returned type. Troubleshooting --------------- Make sure a Java Development Kit (JDK) is installed on your operating system if you want to use PyJNIus on desktop. OpenJDK is known to work, and the Oracle Java JDK should work as well. On windows, make sure `JAVA_HOME` points to your java installation, so PyJNIus can locate the `jvm.dll` file allowing it to start java. This shouldn't be necessary on OSX and Linux, but in case PyJNIus fails to find it, setting `JAVA_HOME` should help. Support ------- If you need assistance, you can ask for help on our mailing list: * User Group : https://groups.google.com/group/kivy-users * Email : kivy-users@googlegroups.com We also have a Discord server: [https://chat.kivy.org/](https://chat.kivy.org/) Contributing ------------ We love pull requests and discussing novel ideas. Check out our [contribution guide](http://kivy.org/docs/contribute.html) and feel free to improve PyJNIus. The following mailing list and IRC channel are used exclusively for discussions about developing the Kivy framework and its sister projects: * Dev Group : https://groups.google.com/group/kivy-dev * Email : kivy-dev@googlegroups.com License ------- PyJNIus is released under the terms of the MIT License. Please refer to the LICENSE file for more information. ## Backers Thank you to all our backers! 🙏 [[Become a backer](https://opencollective.com/kivy#backer)] ## Sponsors Support this project by becoming a sponsor. Your logo will show up here with a link to your website. [[Become a sponsor](https://opencollective.com/kivy#sponsor)]