passing Python list to Java

[Richard van Bemmelen]

How could I do this? I want to call a function on the Java side with a Python list (containing strings) as argument..
The argument should be placed into a Java String array....

Richard

[Richard van Bemmelen]

Here's what I've tried:
In my Python class constructor I used:

self.li = self.gateway.jvm.java.util.ArrayList()

then I use the following code as response on a button click:

if what == 'btnLoad':      # load templates and send them
   res=self.db.select('select name, description from templates')
   self.li = []
   for r in res:
      self.li.append(r[0])
   gateway.entry_point.setQRYresul(self.li)

On the Java side, I have this function:

    public void setQRYresult(ArrayList<String> s){

        this.QRYresult = s;

    }  

But in Python I get this error:

Traceback (most recent call last):

  File "/Users/richard/PycharmProjects/CsServer4j/callback_listener.py", line 27, in notify

    gateway.entry_point.setQRYresul(self.li)

  File "/Library/Python/2.7/site-packages/py4j/java_gateway.py", line 1151, in __call__

    args_command, temp_args = self._build_args(*args)

  File "/Library/Python/2.7/site-packages/py4j/java_gateway.py", line 1121, in _build_args

    [get_command_part(arg, self.pool) for arg in new_args])

  File "/Library/Python/2.7/site-packages/py4j/protocol.py", line 290, in get_command_part

    command_part = REFERENCE_TYPE + parameter._get_object_id()

AttributeError: 'list' object has no attribute '_get_object_id'

Op dinsdag 12 december 2017 19:51:33 UTC+1 schreef Richard van Bemmelen:

[Barthelemy Dagenais]

Hi Richard, did you try this:

https://www.py4j.org/advanced_topics.html#converting-python-collections-to-java-collections

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