Allows to pass JAVA_OPTS to the JVM on windows

jenkins-agent.ps1

@@ -33,7 +33,8 @@ Param(
     $InstanceIdentity = '',
     $Protocols = '',
     $JenkinsJavaBin = '',
-    $JavaHome = $env:JAVA_HOME
+    $JavaHome = $env:JAVA_HOME,
+    $JavaOpts = ''
 )
 
 # Usage jenkins-agent.ps1 [options] -Url http://jenkins -Secret [SECRET] -Name [AGENT_NAME]
@@ -55,7 +56,6 @@ if(![System.String]::IsNullOrWhiteSpace($Cmd)) {
 	# if `docker run` only has one argument, we assume user is running alternate command like `powershell` or `pwsh` to inspect the image
 	Invoke-Expression "$Cmd"
 } else {
-    $AgentArguments = @("-cp", "C:/ProgramData/Jenkins/agent.jar", "hudson.remoting.jnlp.Main", "-headless")
 
     # this maps the variable name from the CmdletBinding to environment variables
     $ParamMap = @{
@@ -69,6 +69,7 @@ if(![System.String]::IsNullOrWhiteSpace($Cmd)) {
         'DirectConnection' = 'JENKINS_DIRECT_CONNECTION';
         'InstanceIdentity' = 'JENKINS_INSTANCE_IDENTITY';
         'Protocols' = 'JENKINS_PROTOCOLS';
+        'JavaOpts' = 'JAVA_OPTS';
     }
 
     # this does some trickery to update the variable from the CmdletBinding
@@ -92,6 +93,14 @@ if(![System.String]::IsNullOrWhiteSpace($Cmd)) {
         }
     }
 
+    $AgentArguments = @()
+
+    if(![System.String]::IsNullOrWhiteSpace($JavaOpts)) {
+        $AgentArguments += @($JavaOpts.split(" "))
+    }
+
+    $AgentArguments += @("-cp", "C:/ProgramData/Jenkins/agent.jar", "hudson.remoting.jnlp.Main", "-headless")
+
     if(![System.String]::IsNullOrWhiteSpace($Tunnel)) {
         $AgentArguments += @("-tunnel", "`"$Tunnel`"")
     }
@@ -117,7 +126,7 @@ if(![System.String]::IsNullOrWhiteSpace($Cmd)) {
     if(![System.String]::IsNullOrWhiteSpace($InstanceIdentity)) {
         $AgentArguments += @('-instanceIdentity', $InstanceIdentity)
     }
-    
+
     if(![System.String]::IsNullOrWhiteSpace($Protocols)) {
         $AgentArguments += @('-protocols', $Protocols)
     }