B4J Question How to avoid javaobject method blocking the ui thread

Sub Class_Globals
    Private fx As JFX
    Private gitJO As JavaObject
    Private gitJOStatic As JavaObject
End Sub

'Initializes the object. You can add parameters to this method if needed.
Public Sub Initialize(path As String)
    gitJOStatic.InitializeStatic("org.eclipse.jgit.api.Git")
    If File.Exists(path,".git")=False Then
        Log("init")
        init(path)
    End If
    gitJO=gitJOStatic.RunMethodJO("open",Array(getFile(path)))
End Sub

Sub getFile(path As String) As JavaObject
    Dim fileJO As JavaObject
    fileJO.InitializeNewInstance("java.io.File",Array(path))
    Return fileJO
End Sub

Public Sub init(path As String)
    gitJOStatic.RunMethodJO("init",Null).RunMethodJO("setDirectory",Array(getFile(path))).RunMethodJO("call",Null)
End Sub

Public Sub push(username As String,password As String,remoteName As String,branchName As String) As ResumableSub
    Sleep(0)
    Try
        Dim PushCommand As JavaObject
        PushCommand=gitJO.RunMethodJO("push",Null)
        PushCommand.RunMethodJO("setRemote",Array(remoteName))
        PushCommand.RunMethodJO("add",Array(branchName))
        If username<>"" Then
            Dim cp As JavaObject
            cp=setCredentialProvider(username,password)
            PushCommand.RunMethod("setCredentialsProvider",Array(cp))
        End If
        PushCommand.RunMethodJo("call",Null)
    Catch
        Log(LastException)
        Return "error"&LastException.Message
    End Try
    Return "success"
End Sub

wait for (projectGit.push(username,password,"origin","master")) complete (result As String)
    If result.StartsWith("error") Then
        fx.Msgbox(Main.MainForm,"Push Failed","")
    End If