adapt Readme code example and introduce test class to validate code example syntax

README.md

@@ -101,6 +101,8 @@ Clustering:
 
 The new API makes it easy to integrate JPlag's plagiarism detection into external Java projects:
 
+<!-- To assure that the code example is always correct, it must be kept in sync
+with [`ReadmeCodeExampleTest#testReadmeCodeExample`](core/src/test/java/de/jplag/special/ReadmeCodeExampleTest.java). -->
 ```java
 Language language = new de.jplag.java.Language();
 Set<File> submissionDirectories = Set.of(new File("/path/to/rootDir"));
@@ -108,11 +110,15 @@ File baseCode = new File("/path/to/baseCode");
 JPlagOptions options = new JPlagOptions(language, submissionDirectories, Set.of()).withBaseCodeSubmissionDirectory(baseCode);
 
 JPlag jplag = new JPlag(options);
-JPlagResult result = jplag.run(); // Exception handling required here
-
-// Optional
-ReportObjectFactory reportObjectFactory = new ReportObjectFactory();
-reportObjectFactory.createAndSaveReport(result, "/path/to/output");
+try {
+    JPlagResult result = jplag.run();
+     
+    // Optional
+    ReportObjectFactory reportObjectFactory = new ReportObjectFactory();
+    reportObjectFactory.createAndSaveReport(result, "/path/to/output");
+} catch (ExitException e) {
+    // error handling here
+}
 ```
 
 ## Contributing

core/src/test/java/de/jplag/special/ReadmeCodeExampleTest.java

@@ -0,0 +1,44 @@
+package de.jplag.special;
+
+import java.io.File;
+import java.util.Set;
+
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+
+import de.jplag.JPlag;
+import de.jplag.JPlagResult;
+import de.jplag.Language;
+import de.jplag.exceptions.ExitException;
+import de.jplag.options.JPlagOptions;
+import de.jplag.reporting.reportobject.ReportObjectFactory;
+
+/**
+ * Test class to validate the code example syntax used in the Readme. As the examples use fictional file paths,
+ * executing the tests would fail.
+ */
+@Disabled("Not an actual test class. Used to validate Readme test example syntax")
+class ReadmeCodeExampleTest {
+    /**
+     * Minimal example for using JPlag. To assure that the Readme is always correct, the method's body must be kept in sync
+     * with the code example in `Readme.md`.
+     */
+    @Test
+    void testReadmeCodeExample() {
+        Language language = new de.jplag.java.Language();
+        Set<File> submissionDirectories = Set.of(new File("/path/to/rootDir"));
+        File baseCode = new File("/path/to/baseCode");
+        JPlagOptions options = new JPlagOptions(language, submissionDirectories, Set.of()).withBaseCodeSubmissionDirectory(baseCode);
+
+        JPlag jplag = new JPlag(options);
+        try {
+            JPlagResult result = jplag.run();
+
+            // Optional
+            ReportObjectFactory reportObjectFactory = new ReportObjectFactory();
+            reportObjectFactory.createAndSaveReport(result, "/path/to/output");
+        } catch (ExitException e) {
+            // error handling here
+        }
+    }
+}