SONARJAVA-6117 S8433 should not raise issue for classes without superclass declared (#5453)

Author: asya-vorobeva

java-checks-test-sources/default/src/main/files/non-compiling/checks/FlexibleConstructorBodyValidationCheckSample.java

@@ -94,7 +94,7 @@ public LargeCoffee(int water, int milk) {
     public LargeCoffee(String name) {
       super(100, 100);
       this.name = name;
-      if (!isValidName(name)) { // NonCompliant
+      if (!isValidName(name)) { // Noncompliant
         throw new IllegalArgumentException();
       }
     }
@@ -166,4 +166,24 @@ public NestedIfCoffee(int water, int milk) {
       }
     }
   }
+
+  // Test when there is no superclass
+  static class NoSuperclassCoffee {
+    private int water;
+    private int milk;
+    private static final int MAX_SIZE = 500;
+
+    public NoSuperclassCoffee(int water, int milk) {
+      if (water + milk > MAX_SIZE) { // Compliant: no superclass and no this(...) call
+        throw new IllegalArgumentException();
+      }
+    }
+
+    public NoSuperclassCoffee(int water) {
+      this(water, 0);
+      if (water <= 0) { // Noncompliant {{Move this validation logic before the super() or this() call.}}
+        throw new IllegalArgumentException();
+      }
+    }
+  }
 }

java-checks/src/main/java/org/sonar/java/checks/FlexibleConstructorBodyValidationCheck.java

@@ -28,6 +28,7 @@
 import org.sonar.plugins.java.api.JavaVersionAwareVisitor;
 import org.sonar.plugins.java.api.semantic.MethodMatchers;
 import org.sonar.plugins.java.api.semantic.Symbol;
+import org.sonar.plugins.java.api.semantic.Type;
 import org.sonar.plugins.java.api.tree.BaseTreeVisitor;
 import org.sonar.plugins.java.api.tree.BlockTree;
 import org.sonar.plugins.java.api.tree.ExpressionStatementTree;
@@ -90,8 +91,9 @@ public void visitNode(Tree tree) {
 
     // Get statements after the constructor call
     List<StatementTree> statements = body.body();
-    if (constructorCallIndex == statements.size() - 1) {
-      // No statements after constructor call
+    if (constructorCallIndex == statements.size() - 1
+      || (constructorCallIndex == -1 && hasNoExplicitSuperClass(constructor))) {
+      // No statements after constructor call or no superclass and no constructor call
       return;
     }
 
@@ -129,6 +131,11 @@ private static int findConstructorCallIndex(BlockTree body) {
     return -1;
   }
 
+  private static boolean hasNoExplicitSuperClass(MethodTree constructor) {
+    Type superClass = constructor.symbol().enclosingClass().superClass();
+    return (superClass == null || superClass.is("java.lang.Object"));
+  }
+
   /**
    * Check if a statement is a validation statement (conditionally throws exception or calls validation method).
    *