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Unable to Debug/Attch Java Maven on Vscode

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
java, vscode

Research direction

Start by reproducing the failure with the shown setting.json and Java launch configuration, then inspect the java-debug log around AttachRequestHandler.java and the connection-refused error. Compare launch and attach behavior on the reported Windows and JDK versions; done means the debugger remains connected and can attach to the selected Java process.

Written by the indexing model from the issue text.

Description

ai-triaged attach question

Unable to debug Java Maven Project.

Environment
  • Operating System: Win10 Enterprise . Build No : 19045.3208 version : 22H2
  • JDK version: 1.8.0_281
  • Visual Studio Code version: 1.81.1 User Setup
  • Java extension version: 0.25.13
  • Java Debugger extension version: v0.54.0
Steps To Reproduce
  1. Vs code setting.json
{
    
    "update.mode": "none",
    "workbench.startupEditor": "none",
    "telemetry.telemetryLevel": "off",
    "java.autobuild.enabled": false,
    "java.configuration.runtimes": [
        {
            "name": "JavaSE-1.8",
            "default": true,
            "path": "C:\\Program Files\\Java\\jdk1.8.0_281"
        }
    ]
}
  1. java debug log file

!ENTRY java-debug 1 0 2023-08-29 22:05:54.430
!MESSAGE Trying to attach to remote debuggee VM localhost:61739 .

!ENTRY java-debug 4 0 2023-08-29 22:05:54.468
!MESSAGE [error response][attach]: Failed to attach to remote debuggee VM. Reason: java.net.ConnectException: Connection refused: connect
!STACK 0
com.microsoft.java.debug.core.DebugException: Failed to attach to remote debuggee VM. Reason: java.net.ConnectException: Connection refused: connect
at com.microsoft.java.debug.core.adapter.AdapterUtils.createCompletionException(AdapterUtils.java:266)
at com.microsoft.java.debug.core.adapter.handler.AttachRequestHandler.handle(AttachRequestHandler.java:81)
at com.microsoft.java.debug.core.adapter.DebugAdapter.lambda$dispatchRequest$0(DebugAdapter.java:94)
at java.base/java.util.concurrent.CompletableFuture.uniComposeStage(Unknown Source)
at java.base/java.util.concurrent.CompletableFuture.thenCompose(Unknown Source)
at com.microsoft.java.debug.core.adapter.DebugAdapter.dispatchRequest(DebugAdapter.java:93)
at com.microsoft.java.debug.core.adapter.ProtocolServer.dispatchRequest(ProtocolServer.java:118)
at com.microsoft.java.debug.core.protocol.AbstractProtocolServer.lambda$new$0(AbstractProtocolServer.java:81)
at io.reactivex.internal.observers.LambdaObserver.onNext(LambdaObserver.java:63)
at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.java:201)
at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:255)
at io.reactivex.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:66)
at io.reactivex.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:57)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)
Caused by: java.net.ConnectException: Connection refused: connect
at java.base/sun.nio.ch.Net.connect0(Native Method)
at java.base/sun.nio.ch.Net.connect(Unknown Source)
at java.base/sun.nio.ch.Net.connect(Unknown Source)
at java.base/sun.nio.ch.NioSocketImpl.connect(Unknown Source)
at java.base/java.net.SocksSocketImpl.connect(Unknown Source)
at java.base/java.net.Socket.connect(Unknown Source)
at java.base/java.net.Socket.connect(Unknown Source)
at java.base/java.net.Socket.(Unknown Source)
at java.base/java.net.Socket.(Unknown Source)
at org.eclipse.jdi.internal.connect.SocketTransportService$2.run(SocketTransportService.java:147)
... 1 more

Launch setting file

{
				"type": "java",
				"name": "Attach Service",
				"request": "attach",
				"processId" : "${command:PickJavaProcess}",
				"timeout": 300000

			}
Current Result

When the type is launch in Launch setting , the debugger starts but after a certain time period the debugger stops , but application is in running mode in the backend . on Debugger console I can see "ERROR: transport error 202: recv error: Connection reset by peer".
So I tried to do attach java process , Vscode is not able to attach , it shows the java process on popup , when I click on it , it throws error dialog saying "Failed to attach remote debuggee VM. Reason java.net.connectException:connection refused connect"

Expected Result

debugger should work

Additional Informations

Back 5/6months ago , I was able to do the debugging correct with the same project on vscode , then I recently updated it to debug the same project and its throwing exception now.

Dominant language
TypeScript
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Avg merge
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Merged PRs (30d)
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