PowerShell ISE: Strange output when executing java -version

Question

In one of my powershell scripts - before starting a Java program - I am echoing the version of the java being used. The PS code looks quite harmless like so:

...
Write-Output "Java version:"
Write-Output "-------------"
java -version
...

The above snippet works perfectly, when I execute in a normal powershell window or as part of the startup script. The output is as expected:

Java version:
-------------
java version "1.8.0_202"
Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
Java HotSpot(TM) 64-Bit Server VM (build 25.202-b08, mixed mode)

But when I execute the exactly same inside the PowerShell ISE (which I normally like to use as it is often quite helpful and convenient when developing and debugging scripts) I get:

Java version:
-------------
java : java version "1.8.0_202"
At D:\Projects\gwtp-demo\mms-specifics\etc\powershell\define_gwtp-demo_profile.ps1:50 char:1
+ java -version
+ ~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (java version "1.8.0_202":String) [], RemoteException
    + FullyQualifiedErrorId : NativeCommandError

Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
Java HotSpot(TM) 64-Bit Server VM (build 25.202-b08, mixed mode)

What's wrong here? Why do I get this additional PS gibberish here? It seems as if PS (or the ISE?) is trying to somehow interpret that output (which is of course NOT what I want or expect. How would I have to call this "correctly" (in PS terms) to avoid such additional output?

It's treating the response from `java -version` as a command — GTBebbo, Apr 11 '20 at 13:08

js2010 · Answer 1 · 2020-04-11T15:54:19.903

Any command that writes to standard error will generate a remote exception in the ISE (or invoke-command). ISE creates a runspace to run commands in. For example, redirecting the standard error to $null results in no output:

java -version 2>$null

Here's a workaround:

java -version 2>&1 | select-string version

java version "1.8.0_241"

Or use get-package, which could apply to any software:

get-package '*java 8*'

Name                        Version         Source                           ProviderName
----                        -------         ------                           ------------
Java 8 Update 241           8.0.2410.7      C:\Program Files (x86)\Java\j... msi

By the way, you might want to switch to OpenJDK/AdoptOpenJDK, because of the license change.

Vscode doesn't behave like this.

PowerShell ISE: Strange output when executing java -version

1 Answers1