Minor syntactical fixes.

jplag.cli/src/main/java/de/jplag/CommandLineArgument.java

@@ -161,8 +161,8 @@ public enum CommandLineArgument {
                 .or(() -> argumentGroup.map(groupHelper::getArgumentGroup)).orElse(parser);
 
         Argument argument = argContainer.addArgument(flag).help(description);
-        choices.ifPresent(it -> argument.choices(it));
-        defaultValue.ifPresent(it -> argument.setDefault(it));
+        choices.ifPresent(argument::choices);
+        defaultValue.ifPresent(argument::setDefault);
         action.ifPresent(argument::action);
         metaVar.ifPresent(argument::metavar);
         argument.type(type);

jplag.frontend.csharp-6/src/main/java/de/jplag/csharp/grammar/CSharpLexerBase.java

@@ -14,8 +14,8 @@ abstract class CSharpLexerBase extends Lexer {
     }
 
     protected int interpolatedStringLevel;
-    protected Stack<Boolean> interpolatedVerbatiums = new Stack<Boolean>();
-    protected Stack<Integer> curlyLevels = new Stack<Integer>();
+    protected Stack<Boolean> interpolatedVerbatiums = new Stack<>();
+    protected Stack<Integer> curlyLevels = new Stack<>();
     protected boolean verbatium;
 
     protected void OnInterpolatedRegularStringStart() {

jplag/src/main/java/de/jplag/SubmissionSet.java

@@ -178,7 +178,7 @@ public class SubmissionSet {
         }
 
         long duration = System.currentTimeMillis() - startTime;
-        String timePerSubmission = submissions.size() > 0 ? Long.toString(duration / submissions.size()) : "n/a";
+        String timePerSubmission = submissions.isEmpty() ? "n/a" : Long.toString(duration / submissions.size());
         logger.trace("Total time for parsing: " + TimeUtil.formatDuration(duration));
         logger.trace("Time per parsed submission: " + timePerSubmission + " msec");
     }