UnsupportedOperationException throwing in Language Server for Liberty

[gilbysunil14]

LCLS output tab include the following exception:

Oct 15, 2024 2:44:21 PM org.eclipse.lsp4j.jsonrpc.RemoteEndpoint handleNotification
WARNING: Notification threw an exception: {
  "jsonrpc": "2.0",
  "method": "$/setTrace",
  "params": {
    "value": "off"
  }
}
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
	at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.lambda$null$0(GenericEndpoint.java:67)
	at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.notify(GenericEndpoint.java:152)
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.handleNotification(RemoteEndpoint.java:220)
	at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.consume(RemoteEndpoint.java:187)
	at io.openliberty.tools.langserver.common.ParentProcessWatcher.lambda$apply$0(ParentProcessWatcher.java:154)
	at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.handleMessage(StreamMessageProducer.java:194)
	at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.listen(StreamMessageProducer.java:94)
	at org.eclipse.lsp4j.jsonrpc.json.ConcurrentMessageProcessor.run(ConcurrentMessageProcessor.java:113)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
	at java.base/java.lang.Thread.run(Thread.java:1595)
Caused by: java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:118)
	at java.base/java.lang.reflect.Method.invoke(Method.java:586)
	at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.lambda$null$0(GenericEndpoint.java:65)
	... 12 more
Caused by: java.lang.UnsupportedOperationException
	at org.eclipse.lsp4j.services.LanguageServer.setTrace(LanguageServer.java:125)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	... 14 more

[gilbysunil14]

Found similar issue in eclipse-jdtls repo (eclipse-jdtls/eclipse.jdt.ls#2891) where an UnsupportedOperationException is thrown at org.eclipse.lsp4j.services.LanguageServer.setTrace. A proposed solution can be found at eclipse-jdtls/eclipse.jdt.ls#2893 to make the '$/setTrace' as empty to avoid throwing UnsupportedOperationException.

A similar change for setTrace() as was done in eclipse-lsp4jakarta: eclipse/lsp4jakarta#531