Added CLI toggle for Match Merging

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

@@ -223,7 +223,8 @@ private static ClusteringOptions getClusteringOptions(CliOptions options) {
     }
 
     private static MergingParameters getMergingParameters(CliOptions options) {
-        return new MergingParameters().withMergeBuffer(options.merging.mergeBuffer).withSeperatingThreshold(options.merging.seperatingThreshold);
+        return new MergingParameters().withEnable(options.merging.enable).withMergeBuffer(options.merging.mergeBuffer)
+                .withSeperatingThreshold(options.merging.seperatingThreshold);
     }
 
     private String generateDescription() {

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

@@ -113,12 +113,15 @@ public static class ClusteringEnabled {
     }
 
     public static class Merging {
+        @Option(names = {"--match-merging"}, description = "Enables match merging (default: false)%n")
+        public boolean enable;
+
         @Option(names = {
-                "--merge-buffer"}, description = "Defines how much lower the length of a match can be than the minimum match length (default: 0)\n")
+                "--merge-buffer"}, description = "Defines how much lower the length of a match can be than the minimum match length (default: 0)%n")
         public int mergeBuffer;
 
         @Option(names = {
-                "--seperating-threshold"}, description = "Defines how many token there can be between two neighboring matches (default: 0)\n")
+                "--seperating-threshold"}, description = "Defines how many token there can be between two neighboring matches (default: 0)%n")
         public int seperatingThreshold;
 
     }

core/src/main/java/de/jplag/JPlag.java

@@ -74,7 +74,9 @@ public static JPlagResult run(JPlagOptions options) throws ExitException {
         JPlagResult result = comparisonStrategy.compareSubmissions(submissionSet);
 
         // Use Match Merging against obfuscation
-        result = new MatchMerging(result, options).run();
+        if (options.mergingParameters().enable()) {
+            result = new MatchMerging(result, options).run();
+        }
 
         if (logger.isInfoEnabled())
             logger.info("Total time for comparing submissions: {}", TimeUtil.formatDuration(result.getDuration()));

core/src/main/java/de/jplag/merging/MergingParameters.java

@@ -5,17 +5,21 @@
  * @param mergeBuffer describes how shorter a match can be than the Minimum Token Match (Defaults to 0).
  * @param seperatingThreshold describes how many tokens can be between to neighboring matches (Defaults to 0).
  */
-public record MergingParameters(int mergeBuffer, int seperatingThreshold) {
+public record MergingParameters(boolean enable, int mergeBuffer, int seperatingThreshold) {
 
     public MergingParameters() {
-        this(0, 0);
+        this(false, 0, 0);
+    }
+
+    public MergingParameters withEnable(boolean enable) {
+        return new MergingParameters(enable, mergeBuffer, seperatingThreshold);
     }
 
     public MergingParameters withMergeBuffer(int mergeBuffer) {
-        return new MergingParameters(mergeBuffer, seperatingThreshold);
+        return new MergingParameters(enable, mergeBuffer, seperatingThreshold);
     }
 
     public MergingParameters withSeperatingThreshold(int seperatingThreshold) {
-        return new MergingParameters(mergeBuffer, seperatingThreshold);
+        return new MergingParameters(enable, mergeBuffer, seperatingThreshold);
     }
 }

core/src/test/java/de/jplag/merging/MergingTest.java

@@ -25,7 +25,7 @@
 /**
  * This class extends on {@link TestBase} and performs several test on Match Merging, in order to check its
  * functionality. Therefore it uses two java programs and feds them into the JPlag pipeline. Results are stored before-
- * and after Match Merging and used for all tests.
+ * and after Match Merging and used for all tests. The two samples are from PROGpedia and under the CC BY 4.0 license.
  */
 class MergingTest extends TestBase {
     private JPlagOptions options;
@@ -37,7 +37,7 @@ class MergingTest extends TestBase {
     private final int SEPERATING_THRESHOLD = 2;
 
     MergingTest() throws ExitException {
-        options = getDefaultOptions("merging").withMergingParameters(new MergingParameters(MERGE_BUFFER, SEPERATING_THRESHOLD));
+        options = getDefaultOptions("merging").withMergingParameters(new MergingParameters(true, MERGE_BUFFER, SEPERATING_THRESHOLD));
 
         GreedyStringTiling coreAlgorithm = new GreedyStringTiling(options);
         ComparisonStrategy comparisonStrategy = new ParallelComparisonStrategy(options, coreAlgorithm);