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Get same JAVA compilation error as in PowerShell or CMD in Visual Studio Code

I'm on latest Windows 10. I have JDK 15. Latest Visual Studio Code (System). In VS Code, I have half of the Java Extension Pack Installed, i.e Language Support for Java (Red Hat) | Debugger for Java (Microsoft) | Visual Studio IntelliCode (Microsoft). So I did that to just get that run button on the top right (the default installed VS Code didn't have that run button for JAVA programs), below the close button, to that I can run the JAVA programs inside the VS Code. I didn't wanna go out to the directory then open Power Shell or CMD and then write java filename.java and run the program...
Now the issue is that when I click the run button, I think, a Power Shell is opened inside the VS Code and then something other than "java FileName.java" is being written. Because of that I can't really see what the compilation error is. I can only see the line number where the problem is, not actually the solution for that. || If I run the same in the PowerShell outside the VS Code with this "java FileName.java", I can see that there is some issue at x line and also the solution for the same.
So I wanted to know if there is any way to get this type of output inside the Visual Studio Code.
Or if there is any way that Instead of writing a lot of thing like this, we can simple tell the Visual Studio Code to run "java fileName.java" inside VS Code when I click the Run Button at the top.
EDIT:
The Code that I'm running is this one.....
File Name - test.java
import java.io.*;
public class SOPFileTest{
public static void main(String arr[]){
try{
// Creating a File object that represents the disk file.
PrintStream o = new PrintStream(new File("A.txt"));
// Store current System.out before assigning a new value
PrintStream console = System.out;
// Assign o to output stream
System.setOut(o);
System.out.println("Test 1");
// Use stored value for output stream
System.setOut(console);
System.out.println("Test 2");
}
catch(Exception e){
System.out.println(e.getMessage());
}
}
Now I've noticed somethings, they are:
-When (FileName == Class Name)
---Then (VS Code)
-----Prints the Last System.out.println in the console
-----A.txt is not created / written inside
---Then (Powershell)
-----Prints the Last System.out.println in the console
-----A.txt is created and/or written inside
-When (FileName != Class Name)
---Then (VS Code)
-----shows the error same as the image that I included above.
---Then (Powershell)
-----Prints the Last System.out.println in the console
-----A.txt is created and/or written inside
So powershell works as I intend it would, the VS Code isn't...

If the filename is different from ClassName, java extension will detect it and throws probelms, which is build failed and you can choose if continue:
If you choose proceed, there should be:
[UPDATE -- Screenshot in Powershell:]
It's about the same as problems shown in VS Code.
Java extension requires class must be defined in its own file, so filename should be as the same as ClassName, then everything works well, no matter in integrated Terminal in VS Code, or in the PowerShell outside VS Code:
So I wanted to know if there is any way to get this type of output
inside the Visual Studio Code.
Keeping the filename and classname same makes sure it could be built and compiled successfully, which is the first step.
And the text file should be generated in current working directory, check it in your file explorer.

java.lang.NoSuchMethodError - Ljava/lang/String;)Ljava/lang/String;

My code is giving an error below;
Exception in thread "main" java.lang.NoSuchMethodError:
com/myApp/Client.cypherCBC(Ljava/lang/String;)Ljava/lang/String;
But it's working fine in an another local environment. My code so far is below;
try {
System.out.println("Encrypted CBC passwd : "
+ Client.cypherCBC("CypherThePassword"));
} catch (Exception e) {
e.printStackTrace();
}

This is due to a run-time JAR or class mismatch. the "Client" class which was there at the time you compile your application has a static method "cypherCBC" which gets String parameter, but at run-time class loader has loaded the "Client" class which doesn't have that kind of method (same name with same signature).
if you can debug the application at runtime, put a break-point at the line which exception was thrown, then try to evaluate following expression,
Client.class.getResource("Client.class")
, then you can find where the class has been leaded from, then you can decompile and try to troubleshoot the issue.

I got the same error while running a web application in Weblogic.
The reason for this error is there are two versions of classes are in the environment.To fix this you have to figure out which .class is using at the run time.
I used following to identify which class is loaded at run time.
-verbose:class

There is a duplicate class on your classpath.
So, That is why JVM is getting confused that which one needs to pick because both classes have a same method with a different signature that you are trying to call.

procrun in --StartMode=Jvm running main that throws exception does not terminate

Trying out Apache procrun I see a behaviour that I do not understand. It boils down to the main method of the Java program throwing an exception. This is not logged anywhere and the Windows service does not stop. To investigate further I changed the main method to
public static void main(String[] args) throws Exception {
if (args.length<10000000) {
throw new Exception("one exception right away");
}
...
}
When I install this as a service with prunsrv.exe and then start it, it starts without problems and produces no log output whatsoever. In particular the service does not stop.
For reference, here is how the service is installed with procrun:
& $procrun "//$operation//$service" `
--DisplayName="$service" `
--Description="$service" `
--DependsOn="$depends" `
--Startup=auto `
--Install="$procrun" `
--Jvm="$JVM" `
--Classpath="$cp" `
--Environment="PATH=$env:JAVA_HOME\bin" `
--JavaHome="$env:JAVA_HOME" `
--StartPath="c:\Search" `
--JvmOptions="-Xmx512M;-Xms512M;-Djava.awt.headless=true" `
--StartMode="jvm" `
--StartClass="$classname" `
--LogPath="c:\Search\std-logs" `
--LogPrefix="procrun-$service" `
--LogLevel="Debug" `
--StdError="c:\Search\std-logs\stderr-$no0" `
--StdOutput="c:\Search\std-logs\stdout-$no0" `
--StartParams="(unused)"
I would have expected that the service stops right away and I find some log output in the stderr/stdout files, but nothing. Can anyone explain this?
EDIT: Oh my, it seems like procrun swallows java.lang.Error (in my case java.lang.noClassDefFoundError) instead of screaming, shouting and exiting.

After I wrapped a catch(Throwable) around the main, logging whatever popped out and then exiting without re-throwing, I saw the problem. I got a java.lang.NoClassDefFoundError.
Bottom line: procrun seems to swallow error type exceptions and does not even terminate if one is thrown in the called Java program.
Created an issue: https://issues.apache.org/jira/browse/DAEMON-344

Running non-existing jar does not cause any expection/error

Please, consider the following snippet which is being run from Eclipse.
Even though the external jar file does not exist no Exception is thrown and process is not null. Why is it so?
try {
Process process = Runtime.getRuntime().exec("java -jar NonExisting.jar");
if (process == null)
System.out.println("process = null");
else
System.out.println(process);
} catch (IOException e) {
System.err.println(e);
}
It prints
java.lang.ProcessImpl#1a4d139
If I run it manully from command line then there is an error:
C:\Users\workspace\Project\src>java -jar NonExisting.jar
Error: Unable to access jarfile NonExisting.jar

Process.waitFor() gives you the exit code of the spawned process, and is likely returning a non-zero (i.e. error) value. You should check this value, and collect the stdout/err at the same time (see here for more info). stderr will likely report an error.
All you're currently doing is confirming that the process has been invoked. The process then tries/fails to load the jar file, and that's when it exists and reports an error.

The process was created and finished. You should check the return value of the Process object. An exception will be thrown if there is a problem with the creation of the new process, so here you don't get an exception.

Whoa, this is quite ugly :-) Why dont you start the Main Methd of the jar in a new thread? Well you should check the exit status of the process:
http://en.wikipedia.org/wiki/Exit_status
http://docs.oracle.com/javase/1.4.2/docs/api/java/lang/Process.htm
You are basically forking the process so you cannot get exceptions or anything java specific from this, you need to deal with the new process, like any other OS specific app.

Capturing a java NoClassDefFoundError thrown by program called via shell script

I have a java program which is a compiler and executor for Jasper Reports and is called via shell script on our reports server.
I just fixed a bug caused by a missing dependancy, but it took me a while to figure out what was going wrong. Normally, problems caused by the compile process are captured, recorded to a log file and emailed to the relevant person. As this was a NoClassDefFoundError, it basically exited the program and failed in a silent manner from the users perspective.
Is there any way for me to capture errors like this one so that they can also be emailed away? I have the authority to modify the executing shell script.

Typically errors are not caught by application code and are thrown to JVM level where they are printed to STDERR. So, your way to track this error is to redirect STDERR to file:
java -cp YourMain 1>stdout.log 2>stderr.log
You can also put both STDOUT and STDERR together:
java -cp YourMain 1>&2 2>wholelog.log
There is a lot of reference about stream redirection in web. You can take a look there if my examples do not satisfy you. And it a depends on your OS.

Just can catch the error i.e.
try {
numericDefinition = new net.sf.cb2xml.def.BasicNumericDefinition(
binName, binarySizes, SynchronizeAt, usePositive, floatSynchronize, doubleSynchronize
);
} catch (NoClassDefFoundError e) {
System.out.println("Class Not Found: " + e.getMessage());
}
You do need to be very careful of your coding though, it is easy to get NoClassDefFoundError thrown at class initialisation time and not get into to the try .. catch block.
The NoClassDefFoundError will be thrown the first time a class is refereneced which could be when could when a class uses a class which uses a class which uses a class ... which uses a class that references a class that does not exist.
The following may fail with NoClassDefFoundError at class initialization because of the import.
import net.sf.cb2xml.def.BasicNumericDefinition; // could cause the NoClassDefFoundError
...........
try {
numericDefinition = new BasicNumericDefinition(
binName, binarySizes, SynchronizeAt, usePositive, floatSynchronize, doubleSynchronize
);
} catch (NoClassDefFoundError e) {
System.out.println("Class Not Found: " + e.getMessage());
}