Read external_app_* settings when needed ...

... because static initialization might read them too early

Author: kasemir

core/framework/src/main/java/org/phoebus/framework/workbench/ApplicationService.java

@@ -59,7 +59,7 @@ private ApplicationService()
         }
 
         // External applications, defined in preferences
-        for (String definition : WorkbenchPreferences.external_apps)
+        for (String definition : WorkbenchPreferences.getExternalApps())
         {
             if (definition.isEmpty())
                 continue;
@@ -181,7 +181,7 @@ public static <AI extends AppInstance> AI createInstance(final String name, fina
      */
     public static List<String> getExtensionsHandledByExternalApp(){
         List<String> extensionsHandledByExternalApp = new ArrayList<>();
-        for (String definition : WorkbenchPreferences.external_apps) {
+        for (String definition : WorkbenchPreferences.getExternalApps()) {
             if (definition.isEmpty()) {
                 continue;
             }

core/framework/src/main/java/org/phoebus/framework/workbench/WorkbenchPreferences.java

@@ -8,37 +8,58 @@
 package org.phoebus.framework.workbench;
 
 import java.io.File;
+import java.util.ArrayList;
 import java.util.Collection;
+import java.util.List;
+import java.util.logging.Level;
 import java.util.logging.Logger;
-import java.util.stream.Collectors;
+import java.util.prefs.Preferences;
 
 import org.phoebus.framework.preferences.AnnotatedPreferences;
 import org.phoebus.framework.preferences.Preference;
-import org.phoebus.framework.preferences.PreferencesReader;
 
 /** Workbench Preferences
  *  @author Kay Kasemir
  */
 public class WorkbenchPreferences
 {
+    // This class gets initialized quite early because other code uses this logger.
+    // The external apps are thus read on demand via getExternalApps(),
+    // they are not constructed in the static... code below because
+    // that might happen before all the `-settings` from the command line have been applied.
+
     /** Logger for the 'workbench' package */
     public static final Logger logger = Logger.getLogger(WorkbenchPreferences.class.getPackageName());
 
     /** directory of external applications */
     @Preference public static File external_apps_directory;
-    
+
     /** Phoebus memento folder name default from $(phoebus.folder.name.preference) System property */
     @Preference public static String  phoebus_folder_name;
-    
+
     /** Phoebus user home directory contents memento default from $(phoebus.user) System property */
     @Preference public static File  phoebus_user;
-    
-    /** external applications */
-    public static final Collection<String> external_apps;
+
+    /** @return external application definitions */
+    public static Collection<String> getExternalApps()
+    {
+        Preferences prefs = Preferences.userNodeForPackage(WorkbenchPreferences.class);
+        final List<String> external = new ArrayList<>();
+        try
+        {
+            for (String key : prefs.keys())
+                if (key.startsWith("external_app_"))
+                    external.add(prefs.get(key, ""));
+        }
+        catch (Exception ex)
+        {
+            logger.log(Level.WARNING, "Cannot read external_app_* entries", ex);
+        }
+        return external;
+    }
 
     static
     {
-        final PreferencesReader prefs = AnnotatedPreferences.initialize(WorkbenchPreferences.class, "/workbench_preferences.properties");
-        external_apps = prefs.getKeys("external_app_.*").stream().map(prefs::get).collect(Collectors.toList());
+        AnnotatedPreferences.initialize(WorkbenchPreferences.class, "/workbench_preferences.properties");
     }
 }