Use toLower with a locale

java/org/contikios/cooja/Cooja.java

@@ -45,6 +45,7 @@
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Locale;
 import java.util.Objects;
 import java.util.Properties;
 import java.util.Random;
@@ -964,7 +965,7 @@ private static Properties getExternalToolsDefaultSettings() {
 
     settings.put("PARSE_COMMAND", "nm -aP $(LIBFILE)");
     settings.put("COMMAND_VAR_NAME_ADDRESS_SIZE", "^(?<symbol>[^.].*?) <SECTION> (?<address>[0-9a-fA-F]+) (?<size>[0-9a-fA-F])*");
-    String osName = System.getProperty("os.name").toLowerCase();
+    String osName = System.getProperty("os.name").toLowerCase(Locale.ROOT);
     if (osName.startsWith("mac os x")) {
       settings.put("PARSE_WITH_COMMAND", "true");
       settings.put("PARSE_COMMAND", "symbols $(LIBFILE)");

java/org/contikios/cooja/ui/ColorUtils.java

@@ -30,6 +30,7 @@
 
 package org.contikios.cooja.ui;
 import java.awt.Color;
+import java.util.Locale;
 
 /**
  * Utility methods for managing colors.
@@ -50,7 +51,7 @@ private ColorUtils() {
      * @see java.awt.Color#decode(String)
      */
     public static Color decodeColor(String colorString) {
-        return colorString == null ? null : switch (colorString.toLowerCase()) {
+        return colorString == null ? null : switch (colorString.toLowerCase(Locale.ROOT)) {
             case "black" -> Color.black;
             case "blue" -> Color.blue;
             case "cyan" -> Color.cyan;

java/se/sics/mspsim/Main.java

@@ -41,6 +41,7 @@
 import java.lang.reflect.InvocationTargetException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Locale;
 import se.sics.mspsim.chip.AT45DB;
 import se.sics.mspsim.chip.M25P80;
 import se.sics.mspsim.platform.GenericNode;
@@ -156,7 +157,7 @@ public static String getNodeTypeByPlatform(String platform) {
       // Try to guess the node type.
       default -> "se.sics.mspsim.platform." + platform + '.'
               + Character.toUpperCase(platform.charAt(0))
-              + platform.substring(1).toLowerCase() + "Node";
+              + platform.substring(1).toLowerCase(Locale.ROOT) + "Node";
     };
   }
 

java/se/sics/mspsim/util/PluginRepository.java

@@ -45,6 +45,7 @@
 import java.io.IOException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.util.Locale;
 import java.util.jar.Attributes;
 import java.util.jar.JarFile;
 import java.util.jar.Manifest;
@@ -111,7 +112,7 @@ private static class JarFilter implements FileFilter {
     @Override
     public boolean accept(File f) {
       if (f.isFile() && f.canRead()) {
-        String name = f.getName().toLowerCase();
+        String name = f.getName().toLowerCase(Locale.ROOT);
         return name.endsWith(".jar");
       }
       return false;