Update PlantumlSession.cs

src/C4Sharp/Models/Plantuml/PlantumlFile.cs

@@ -122,23 +122,11 @@ public static void Export(Diagram diagram, string path, PlantumlSession session)
         /// <summary>
         /// Export Diagram to PNG File
         /// </summary>
-        /// <param name="path">File path</param>
+        /// <param name="pumlPath">File path</param>
         /// <param name="session">Plantuml Session</param>
-        private static void Export(string path, PlantumlSession session)
+        private static void Export(string pumlPath, PlantumlSession session)
         {
-            var jarPath = session.FilePath;
-            var directory = new FileInfo(path);
-
-            var jar = $"-jar {jarPath} -verbose -o \"{directory.Directory.FullName}\" -charset UTF-8";
-
-            var info = new ProcessStartInfo
-            {
-                UseShellExecute = false,
-                FileName = "java",
-                Arguments = $"{jar} {path}"
-            };
-
-            Process.Start(info)?.WaitForExit();
+            session.Execute(pumlPath);
         }
 
         /// <summary>

src/C4Sharp/Models/Plantuml/PlantumlSession.cs

@@ -1,15 +1,53 @@
 using System;
+using System.Diagnostics;
+using System.IO;
+using System.Text;
 using C4Sharp.Models.Diagrams;
 
 namespace C4Sharp.Models.Plantuml
 {
     public class PlantumlSession: IDisposable
     {
-        public string FilePath { get; }
+        private string FilePath { get; }
+        private ProcessStartInfo ProcessInfo { get; }
 
         public PlantumlSession()
         {
             FilePath = PlantumlStream.LoadPlantUmlEngine();
+            ProcessInfo = new ProcessStartInfo
+            {
+                UseShellExecute = false,
+                FileName = "java",
+            };            
+        }
+
+        public PlantumlSessionResult Execute(string puml)
+        {
+            var directory = new FileInfo(puml);
+
+            if (directory.Directory != null)
+            {
+                var results = new StringBuilder();
+
+                var jar = $"-jar {FilePath} -verbose -o \"{directory.Directory.FullName}\" -charset UTF-8";
+                ProcessInfo.Arguments = $"{jar} {puml}";
+                ProcessInfo.RedirectStandardOutput = true;
+                ProcessInfo.StandardOutputEncoding = Encoding.UTF8;
+
+                var process = new Process {StartInfo = ProcessInfo};
+
+                process.OutputDataReceived += (sender, args) =>
+                {
+                    results.AppendLine(args.Data);
+                };
+
+                process.Start();
+                process.WaitForExit();
+
+                return new PlantumlSessionResult(process.ExitCode == 0, results.ToString());
+            }
+
+            return new PlantumlSessionResult(false, "Plantuml file not found");
         }
 
         public void Dispose()

src/C4Sharp/Models/Plantuml/PlantumlSessionResult.cs

@@ -0,0 +1,14 @@
+namespace C4Sharp.Models.Plantuml
+{
+    public class PlantumlSessionResult
+    {
+        public bool Success { get; private set; }
+        public string Messages { get; private set; }
+
+        public PlantumlSessionResult(bool success, string messages)
+        {
+            Success = success;
+            Messages = messages;
+        }
+    }
+}