make the defaults (environment, defaultOptions) unmodifiable

src/de/uni_passau/fim/seibt/gitwrapper/repo/GitWrapper.java

@@ -37,22 +37,25 @@ public class GitWrapper extends ToolWrapper {
     private static final String GIT_VERSION_C = "--version";
     private static final String GIT_VERSION_PREFIX = "git version";
 
-    private static final Map<String, String> env;
+    private static final Map<String, String> environment;
     private static final List<String> defaultOptions;
 
     static {
-        env = new HashMap<>();
-
+        Map<String, String> env = new HashMap<>();
         String locale = "C";
+
         env.put("LANGUAGE", locale);
         env.put("LC_ALL", locale);
         env.put("LANG", locale);
+        environment = Collections.unmodifiableMap(env);
+
+        List<String> defOptions = new ArrayList<>();
 
-        defaultOptions = new ArrayList<>();
-        defaultOptions.add("-c");
-        defaultOptions.add("core.quotePath=false");
-        defaultOptions.add("-c");
-        defaultOptions.add("core.precomposeUnicode=true");
+        defOptions.add("-c");
+        defOptions.add("core.quotePath=false");
+        defOptions.add("-c");
+        defOptions.add("core.precomposeUnicode=true");
+        defaultOptions = Collections.unmodifiableList(defOptions);
     }
 
     /**
@@ -237,6 +240,6 @@ public class GitWrapper extends ToolWrapper {
             Collections.addAll(pars, parameters);
         }
 
-        return exec(workingDirectory, true, env, pars);
+        return exec(workingDirectory, true, environment, pars);
     }
 }