java.lang.NoSuchMethodError: java.nio.ByteBuffer.clear()Ljava/nio/ByteBuffer;

[JulienPalard]

I'm getting this exception while trying the Python scripting interface, I'm using Jython 2.7.1 on Debian:

{{{
URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2019-03-31 21:17:00 +0200 (Sun, 31 Mar 2019)
Build-Date:2019-03-31 20:25:18
Revision:14945
Relative:URL: ^/trunk

Identification: JOSM/1.5 (14945 en) Linux Debian GNU/Linux buster/sid
Memory Usage: 496 MB / 1756 MB (273 MB allocated, but free)
Java version: 1.8.0_201-b09, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: :0.0 1920x1080, :0.1 1920x1080
Maximum Screen Size: 1920x1080

Plugins:
+ scripting (30794)
+ utilsplugin2 (34932)

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- E: Handled by bug report queue: java.lang.NoSuchMethodError: java.nio.ByteBuffer.clear()Ljava/nio/ByteBuffer;

=== REPORTED CRASH DATA ===
BugReportExceptionHandler#handleException:
No data collected.

Warning issued by: BugReportExceptionHandler#handleException

=== STACK TRACE ===
Thread: AWT-EventQueue-0 (17) of main
java.lang.NoSuchMethodError: java.nio.ByteBuffer.clear()Ljava/nio/ByteBuffer;
    at org.python.core.io.BufferedReader.clear(BufferedReader.java:147)
    at org.python.core.io.BufferedReader.<init>(BufferedReader.java:27)
    at org.python.core.PyFile.createBuffer(PyFile.java:227)
    at org.python.core.PyFile.file___init__(PyFile.java:185)
    at org.python.core.PyFile.file___init__(PyFile.java:178)
    at org.python.core.PyFile.<init>(PyFile.java:101)
    at org.python.core.PySystemState.<init>(PySystemState.java:237)
    at org.python.util.PythonInterpreter.threadLocalStateInterpreter(PythonInterpreter.java:81)
    at org.python.jsr223.PyScriptEngine.<init>(PyScriptEngine.java:27)
    at org.python.jsr223.PyScriptEngineFactory.getScriptEngine(PyScriptEngineFactory.java:85)
    at org.openstreetmap.josm.plugins.scripting.model.JSR223ScriptEngineProvider.lambda$getScriptEngine$12(JSR223ScriptEngineProvider.java:307)
    at java.util.Optional.map(Optional.java:215)
    at org.openstreetmap.josm.plugins.scripting.model.JSR223ScriptEngineProvider.getScriptEngine(JSR223ScriptEngineProvider.java:307)
    at org.openstreetmap.josm.plugins.scripting.ui.ScriptExecutor.runScriptWithPluggedEngine(ScriptExecutor.java:255)
    at org.openstreetmap.josm.plugins.scripting.ui.RunScriptService.runScript(RunScriptService.java:180)
    at org.openstreetmap.josm.plugins.scripting.ui.RunScriptService.runScript(RunScriptService.java:147)
    at org.openstreetmap.josm.plugins.scripting.ui.MostRecentlyRunScriptsModel$RunScriptAction.actionPerformed(MostRecentlyRunScriptsModel.java:151)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
    at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:842)
    at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:886)
    at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
    at java.awt.Component.processMouseEvent(Component.java:6539)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
    at java.awt.Component.processEvent(Component.java:6304)
    at java.awt.Container.processEvent(Container.java:2239)
    at java.awt.Component.dispatchEventImpl(Component.java:4889)
    at java.awt.Container.dispatchEventImpl(Container.java:2297)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4904)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4535)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4476)
    at java.awt.Container.dispatchEventImpl(Container.java:2283)
    at java.awt.Window.dispatchEventImpl(Window.java:2746)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
    at java.awt.EventQueue$4.run(EventQueue.java:733)
    at java.awt.EventQueue$4.run(EventQueue.java:731)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
}}}

I just tried to run:

from org.openstreetmap.josm.plugins.scripting.python import JosmPythonPlugin

class HelloWorldPlugin(JosmPythonPlugin):
    def onLoad(self):
        print "onLoad: starting ..."

    def onMapFrameChanged(self, oldFrame, newFrame):
        print "onMapFrameChanged:"
        print "   old frame is: ", oldFrame
        print "   new frame is: ", newFrame

[Gubaer]

Most likely on your system a jython-jar is present, which was compiled with Java 9. Please download the "official" jython jar, i.e. from here, and configure JOSM to use this jar.

Does this solve the problem?

[JulienPalard]

I'm using jython 2.7.1+repack1-2 from http://ftp.fr.debian.org/debian testing/main amd64 Packages is there a way to know against which Java version it was compiled?

[Gubaer]

Python plugins are not supported anymore. Closing this issue.