SONARJAVA-4973 Fix FP on S1118 with Lombok @UtilityClass in automatic…

… analysis (#4960)

Co-authored-by: Dorian Burihabwa <[email protected]>

java-checks/src/main/java/org/sonar/java/filters/LombokFilter.java

@@ -22,6 +22,7 @@
 import java.util.Optional;
 import java.util.Set;
 import javax.annotation.Nullable;
+import org.sonar.java.annotations.VisibleForTesting;
 import org.sonar.java.checks.AtLeastOneConstructorCheck;
 import org.sonar.java.checks.CollectionInappropriateCallsCheck;
 import org.sonar.java.checks.ConstantsShouldBeStaticFinalCheck;
@@ -181,12 +182,32 @@ public void visitAssignmentExpression(AssignmentExpressionTree tree) {
   }
 
   private static boolean usesAnnotation(ClassTree classTree, List<String> annotations) {
+    return usesAnnotation(classTree, annotations, false);
+  }
+
+  private static boolean usesAnnotation(ClassTree classTree, List<String> annotations, boolean shouldCheckAnnotationLocalName) {
     SymbolMetadata classMetadata = classTree.symbol().metadata();
-    return annotations.stream().anyMatch(classMetadata::isAnnotatedWith);
+
+    for(String fullyQualified: annotations) {
+      if(classMetadata.isAnnotatedWith(fullyQualified)) {
+        return true;
+      }
+      // In automatic analysis use only the last part of the annotation.
+      if(shouldCheckAnnotationLocalName && classMetadata.isAnnotatedWith(annotationTypeIdentifier(fullyQualified))) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  @VisibleForTesting
+  static String annotationTypeIdentifier(String fullyQualified) {
+    return fullyQualified.substring(fullyQualified.lastIndexOf('.') + 1);
   }
 
   private static boolean generatesNonPublicConstructor(ClassTree classTree) {
-    if (usesAnnotation(classTree, UTILITY_CLASS)) {
+    if (usesAnnotation(classTree, UTILITY_CLASS, true)) {
       return true;
     }
     SymbolMetadata metadata = classTree.symbol().metadata();

java-checks/src/test/files/filters/LombokFilterWithoutSemantic.java

@@ -1,8 +1,20 @@
 import lombok.experimental.UtilityClass;
 
-// FP happening without semantics.
+class Utility { // WithIssue
+  public static int triple(int in) {
+    return in * 3;
+  }
+}
+
 @UtilityClass
-public class Utility { // WithIssue
+class UtilityAnnotated { // NoIssue
+  public static int triple(int in) {
+    return in * 3;
+  }
+}
+
+@lombok.experimental.UtilityClass
+class UtilityFullyQualified { // NoIssue
   public static int triple(int in) {
     return in * 3;
   }

java-checks/src/test/java/org/sonar/java/filters/LombokFilterTest.java

@@ -18,6 +18,9 @@
 
 import org.junit.jupiter.api.Test;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.sonar.java.filters.LombokFilter.annotationTypeIdentifier;
+
 class LombokFilterTest {
 
   @Test
@@ -32,4 +35,11 @@ void testWithoutSemantic() {
       .withoutSemantic()
       .verify("src/test/files/filters/LombokFilterWithoutSemantic.java", new LombokFilter());
   }
+
+  @Test
+  void testAnnotationTypeIdentifier() {
+    assertThat(annotationTypeIdentifier("noDot")).isEqualTo("noDot");
+    assertThat(annotationTypeIdentifier("one.dot")).isEqualTo("dot");
+    assertThat(annotationTypeIdentifier("many.many.dots")).isEqualTo("dots");
+  }
 }