Could not find or load main class & ERROR: transport error 103: invalid port number specified

[AnqiHuangQiQi]

Error: Could not find or load main class
Caused by: java.lang.ClassNotFoundException

If I take the java command and directly run it, I got these errors

[github-actions]

Hi @AnqiHuangQiQi, I'm an AI Support assistant here to help with your issue. While the team reviews your request, I wanted to provide some possible tips and documentation that might help you in the meantime.

Suggestions:

• Ensure your class is compiled and your classpath points to the output folder:
  • e.g.: javac -d bin src/com/example/Main.java
  • then run: java -cp bin com.example.Main
• Check your debug port configuration (transport error 103) in your launch.json or JVM args:
  • The port must be a valid integer (>0), e.g. -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005
  • In VS Code launch.json, use:

    "configurations": [
      {
        "type": "java",
        "request": "attach",
        "hostName": "127.0.0.1",
        "port": 5005
      }
    ]

• If you still get “Could not find or load main class”, try cleaning the Java Language Server workspace:
  • Command Palette → Java: Clean the Java Language Server Workspace

Duplicate issue worth checking:

• Error: Could not find or load main class (similar missing-class problem)
  • Error: Could not find or load main class redhat-developer/vscode-java#1085

Other references with low confidence

• [Windows non-ASCII folder] Error: Could not find or load main class (locale/encoding issues) • [Windows non-ASCII folder] Error: Could not find or load main class #623
• Error: Could not find or load main class (JDT LS hover request failures) • After a class is repeated multiple times, dd re-enters, and then dd deletes, and there will be no prompt eclipse-jdtls/eclipse.jdt.ls#3270
• org/eclipse/m2e/core/embedder/IMavenExecutionContextFactory class-not-found • org/eclipse/m2e/core/embedder/IMavenExecutionContextFactory #1178

The team will respond to your issue shortly. I hope these suggestions are helpful in the meantime. If this comment helped you, please give it a 👍. If the suggestion was not helpful or incorrect, please give it a 👎. Your feedback helps us improve!