Ghidra: Ghidra finds non-existent class

[j-ratz]

I'm debugging an extension. It's a ProgramTableChooserDialog that contains rows with program and address columns and can navigate to whatever program/address is in a row.

An old ProgramTableChooserDialog version threw an exception. I've written a new version, but I can't get Ghidra to see it. I've even renamed ProgramTableChooserDialog.class to PTCD.c and added the following lines to the script that creates the dialog:
printf("%s\n", ProgramTableChooserDialog.class.getResource('/' + ProgramTableChooserDialog.class.getName().replace('.', '/') + ".class"));
ProgramTableChooserDialog table = new ProgramTableChooserDialog(
tool, null, currentProgram, "Callers", null, false);

The printf writes"null" to the console, as expected. But the ctor runs and eventually throws the old exception. How do I get Ghidra to see the current class file?

I'm using Eclipse (GhidraDev) to launch my project. Although ProgramTableChooserDialog.class doesn't exist, I get the following when I run my script:
null

Error running script: ListCallers.java
java.lang.NullPointerException
at docking.widgets.table.threaded.GThreadedTablePanel.initializeModel(GThreadedTablePanel.java:114)
at docking.widgets.table.threaded.GThreadedTablePanel.(GThreadedTablePanel.java:102)
at ghidra.util.table.GhidraThreadedTablePanel.(GhidraThreadedTablePanel.java:35)
at contrib.util.table.ProgramTableChooserDialog$TableChooserDialogPanel.(ProgramTableChooserDialog.java:347)
at contrib.util.table.ProgramTableChooserDialog.buildMainPanel(ProgramTableChooserDialog.java:112)
at contrib.util.table.ProgramTableChooserDialog.(ProgramTableChooserDialog.java:94)
at ListCallers.run(ListCallers.java:362)

The exception is being thrown because the table row type (ProgramAddressableRowObject) loaded as part of my extension isn't matching my extension ProgramAddressableRowObjectToAddressTableRowMapper's source type. The match is failing, although the 2 classes are the same (both ProgramAddressableRowObject), because the classes are loaded by 2 different class loaders. The row type is loaded by ghidra.app.script.JavaScriptClassLoader@7695fdbc and the mapper's source type is loaded by jdk.internal.loader.ClassLoaders$AppClassLoader@41906a77 (GhidraScript).

I'm using Ghidra 9.1.1 on Windows 10. I'd like to use Ghidra 9.1.2, but it throws an exception when I try to load any of the programs in my project:
2020-04-22 12:02:44 ERROR (TaskBuilder$TaskBuilderTask) Task Error: Loading language 'ARM:LE:32:v8' - Uncaught Exception: java.lang.RuntimeException: org.xml.sax.SAXParseException; lineNumber: 10251; columnNumber: 25; XML document structures must start and end within the same entity. java.lang.RuntimeException: org.xml.sax.SAXParseException; lineNumber: 10251; columnNumber: 25; XML document structures must start and end within the same entity.
at ghidra.xml.ThreadedXmlPullParserImpl.checkForException(ThreadedXmlPullParserImpl.java:122)
at ghidra.xml.ThreadedXmlPullParserImpl.waitForNextElement(ThreadedXmlPullParserImpl.java:168)
at ghidra.xml.ThreadedXmlPullParserImpl.hasNext(ThreadedXmlPullParserImpl.java:154)
at ghidra.xml.ThreadedXmlPullParserImpl.peek(ThreadedXmlPullParserImpl.java:181)
at ghidra.app.plugin.processors.sleigh.symbol.SymbolTable.restoreSymbolHeader(SymbolTable.java:132)
at ghidra.app.plugin.processors.sleigh.symbol.SymbolTable.restoreXml(SymbolTable.java:112)
at ghidra.app.plugin.processors.sleigh.SleighLanguage.restoreXml(SleighLanguage.java:872)
at ghidra.app.plugin.processors.sleigh.SleighLanguage.readSpecification(SleighLanguage.java:842)
at ghidra.app.plugin.processors.sleigh.SleighLanguage.initialize(SleighLanguage.java:133)
at ghidra.app.plugin.processors.sleigh.SleighLanguage.(SleighLanguage.java:101)
at ghidra.app.plugin.processors.sleigh.SleighLanguageProvider.getNewSleigh(SleighLanguageProvider.java:112)
at ghidra.app.plugin.processors.sleigh.SleighLanguageProvider.getLanguage(SleighLanguageProvider.java:99)
at ghidra.program.util.DefaultLanguageService$LanguageInfo.lambda$getLanguage$0(DefaultLanguageService.java:385)
at ghidra.util.task.TaskBuilder$TaskBuilderTask.run(TaskBuilder.java:303)
at ghidra.util.task.Task.monitoredRun(Task.java:126)
at ghidra.util.task.TaskRunner.lambda$startTaskThread$1(TaskRunner.java:94)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: org.xml.sax.SAXParseException; lineNumber: 10251; columnNumber: 25; XML document structures must start and end within the same entity.
at java.xml/com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1243)
at java.xml/com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:635)
at ghidra.xml.ThreadedXmlPullParserImpl$ContentHandlerRunnable.run(ThreadedXmlPullParserImpl.java:267)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
... 3 more

[astrelsky]

It may be that ghidra is using the old ListCallers.class instead of recompiling the script and running that. You can try deleting ListCallers.class and rerunning the script. I've encountered this a few times but always attributed it to my setup since I don't like Eclipse and instead use vscode.

You can find the compiled script class files in %HOMEPATH%/.ghidra/.ghidra_9.1.1_PUBLIC/dev/ghidra_scripts/bin

[j-ratz]

That was the problem...I was focused on the wrong file. Should've thought of that.

Thanks!

[astrelsky]

That was the problem...I was focused on the wrong file. Should've thought of that.

Thanks!

No problem. I think it's because the scripts are only recompiled if the java file is newer then the previously compiled class. If you change a class the script is using, ghidra doesn't know it needs to recompile the script.