Accessing JVM from python

问题

>>> import boilerpipe
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Anaconda\lib\site-packages\boilerpipe\__init__.py", line 10, in <module>
    jpype.startJVM(jpype.getDefaultJVMPath(), "-Djava.class.path=%s" % os.pathsep.join(jars))
  File "C:\Anaconda\lib\site-packages\jpype\_core.py", line 50, in startJVM
    _jpype.startup(jvm, tuple(args), True)
RuntimeError: Unable to load DLL [C:\Program Files\Java\jre7\bin\client\jvm.dll], error = The specified module could not be found.
 at native\common\include\jp_platform_win32.h:58

Tried: Reinstalling jvm

>> import ctypes
>> import os
>> os.chdir(r"<path to Java bin client folder>")
>> ctypes.CDLL("jvm.dll")
Still unable to fix

Edit: Tried code below, still stuck:

from py4j.java_gateway import JavaGateway gateway = JavaGateway() It gives the same error as before.

回答1:

Check Please !

Give a true path ("C:\\Program Files\\Java\\jre7\\bin\client\\jvm.dll")
Check all 32 or 64 bit (my offer always use 32bit Anaconda,JRE7,Python etc.)
Install pywin32 (of course python2.7.9)
Give permission to jvm.dll(can run)
After all is ok, try: import ctypes ctypes.CDLL('C:\\Program Files\\Java\\jre7\\bin\\client\\jvm.dll')

***Maybe can't throw the hook of some java versions i used jre-7u55-windows-i586.exe

i hope helpful ! Best regards !

Works on wine(no bug):

回答2:

Answering because I don't have enough rep for commenting; Try using raw strings instead of the normal ones allowing "\x" escapes. Try:

>>> ctypes.CDLL(r'C:\Program Files (x86)\Java\jre1.8.0_40\bin\client\jvm.dll')

Because the "\..." parts of the string could very well be escapes.

回答3:

The answers above are not sufficient, one also needs to install the Microsoft Visual C++ 2010 Redistributable Package (x86) as per Bjorns answer.

After installed the C++ redistributable:

Set JAVA_HOME environment variable to ("C:\Program Files\Java\jre7")
Use paths as mentioned above to start jvm:

path_to_jvm = "C:\Program Files\Java\jre7\bin\client\jvm.dll"

jpype.startJVM(path_to_jvm)

jpype.startJVM(jpype.getDefaultJVMPath())

回答4:

If you are trying to access JVM on Windows operation system, make sure you have the right version of JVM (32-bit or 64-bit) installed. In my case python was 64-bit and once I installed Java 64-bit, it worked without needing to specify the path or any other extra requirements.

来源：https://stackoverflow.com/questions/32045648/accessing-jvm-from-python

标签

java

python

jvm

boilerpipe