solve #256 , adapt existing config file keys to default configuration

VadereGui/src/org/vadere/gui/projectview/control/ActionLoadProject.java

@@ -80,7 +80,7 @@ public class ActionLoadProject extends AbstractAction {
 
 
 			} else {
-				logger.info(String.format("user canceled loadFromFilesystem project."));
+				logger.info("User canceled loadFromFilesystem project.");
 			}
 		} catch (IOException e1) {
 			e1.printStackTrace();
@@ -88,24 +88,27 @@ public class ActionLoadProject extends AbstractAction {
 	}
 
 	public static void addToRecentProjects(String path) {
-		String listStr = VadereConfig.getConfig().getString("History.recentProjects", "");
-		String str = path; // make sure the new one is at top position
-		if (listStr.length() > 0) {
-			String[] list = listStr.split(",");
-			for (int i = 0; i < list.length; i++) {
+		String existingStoredPaths = VadereConfig.getConfig().getString("History.recentProjects", "");
+		String csvPaths = path; // make sure the new one is at top position -- comma separated paths
+
+		if (existingStoredPaths.length() > 0) {
+			String[] list = existingStoredPaths.split(",");
+			for(int i = 0; i < list.length; i++) {
 				String entry = list[i];
 				if (i < 10 && !entry.equals(path) && Files.exists(Paths.get(entry)))
-					str += "," + entry;
+					csvPaths += "," + entry;
 			}
 		}
+
 		VadereConfig.getConfig().setProperty("History.lastUsedProject", path);
-		VadereConfig.getConfig().setProperty("History.recentProjects", str);
+		VadereConfig.getConfig().setProperty("History.recentProjects", csvPaths);
 		ProjectView.getMainWindow().updateRecentProjectsMenu();
 	}
 
 	public static void loadProjectByPath(ProjectViewModel projectViewModel, String projectFilePath){
 		loadProjectByPath(projectViewModel, projectFilePath, MigrationOptions.defaultOptions());
 	}
+
 	public static void loadProjectByPath(ProjectViewModel projectViewModel, String projectFilePath, MigrationOptions options) {
 		try {
 			VadereProject project = IOVadere.readProjectJson(projectFilePath, options);

VadereUtils/src/org/vadere/util/config/VadereConfig.java

@@ -13,6 +13,7 @@ import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.Locale;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -58,6 +59,8 @@ public class VadereConfig {
     private VadereConfig() {
         createDefaultConfigIfNonExisting();
 
+        LOGGER.info(String.format("Use config file %s", CONFIG_PATH));
+
         // If Vadere was started like "vadere-console.jar --config-file here.txt", search in current working directory.
         String basePath = (CONFIG_PATH.getParent() == null) ? System.getProperty("user.dir") : CONFIG_PATH.getParent().toString() ;
 
@@ -77,6 +80,9 @@ public class VadereConfig {
             LOGGER.error(String.format("Error while reading config file \"%s\": %s", CONFIG_PATH.toString(), ex.getMessage()));
             LOGGER.info("Create and use default config");
         }
+
+        compareAndChangeDefaultKeysInExistingFile();
+
     }
 
     private void createDefaultConfigIfNonExisting() {
@@ -106,6 +112,33 @@ public class VadereConfig {
         }
     }
 
+    private void compareAndChangeDefaultKeysInExistingFile(){
+
+        // The keys of the default config have to match the keys from the existing file!
+        Map<String, String> defaultConfig = getDefaultConfig();
+
+        // first case: if key is missing in existing file then add it but added in to the defaultConfig
+        //   -- usually happens when a new key was introduced
+        for(String key : defaultConfig.keySet()){
+            if(! vadereConfig.containsKey(key)){
+                vadereConfig.setProperty(key, defaultConfig.get(key));
+                LOGGER.info(String.format("Added key %s to file %s with default value because the key was not present "
+                        + "in the file before.", key, CONFIG_PATH));
+            }
+        }
+
+        // Second case: if key was removed from defaultConfig, then it is also removed from the current file
+        //   -- usually happens when a key was removed
+        for(Iterator<String> iter = vadereConfig.getKeys(); iter.hasNext();){
+            String key = iter.next();
+            if(! defaultConfig.containsKey(key)){
+                vadereConfig.clearProperty(key);
+                LOGGER.info(String.format("Removed key %s in file %s because there is no entry in the " +
+                        "\"defaultConfig\" in class VadereConfig.java", key, CONFIG_PATH));
+            }
+        }
+    }
+
     // Static setters
     /**
      * With this setter one can inject a different config file instead of using "~/.config/vadere.conf".
@@ -142,12 +175,14 @@ public class VadereConfig {
 
         String defaultSearchDirectory = System.getProperty("user.home");
 
-        defaultConfig.put("Gui.dataProcessingViewMode", "gui");
-        defaultConfig.put("Gui.toolbar.size", "40");
-        defaultConfig.put("Gui.lastSavePoint", defaultSearchDirectory);
         defaultConfig.put("Density.measurementScale", "10.0");
         defaultConfig.put("Density.measurementRadius", "15");
         defaultConfig.put("Density.standardDeviation", "0.5");
+        defaultConfig.put("Gui.dataProcessingViewMode", "gui");
+        defaultConfig.put("Gui.toolbar.size", "40");
+        defaultConfig.put("Gui.lastSavePoint", defaultSearchDirectory);
+        defaultConfig.put("History.lastUsedProject", null);
+        defaultConfig.put("History.recentProjects", null);
         defaultConfig.put("Messages.language", Locale.ENGLISH.getLanguage());
         defaultConfig.put("Pedestrian.radius", "0.195");
         defaultConfig.put("PostVis.SVGWidth", "1024");