[java-analysis] Check field finality when deciding whether class is immutable

Fixes IDEA-293687 Incorrectly claims "expression is always false"

GitOrigin-RevId: 74a3d8f7b3b0a66a974aa35d55147cbc3336393f

java/java-tests/testData/inspection/dataFlow/fixture/FieldUpdateViaSetter.java

@@ -0,0 +1,25 @@
+// IDEA-293687
+public class FieldUpdateViaSetter {
+  private static final MutableBoolean flag = new MutableBoolean();
+
+  public static void main(String[] args) {
+    for (int i = 0; i < 10; ++i) {
+      if (flag.value && i == 0) {
+        break;
+      }
+      if (flag.value && i == 3) {
+        System.out.println("IDEA thinks we can't get here");
+        break;
+      }
+      flag.setValue(true);
+    }
+  }
+
+  private static final class MutableBoolean {
+    private boolean value;
+
+    public void setValue(boolean newValue) {
+      value = newValue;
+    }
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java

@@ -697,6 +697,7 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
   public void testBoxedDivisionComparison() { doTest(); }
   public void testUnknownComparedToNullable() { doTest(); }
   public void testCastInCatch() { doTest(); }
+  public void testFieldUpdateViaSetter() { doTest(); }
   public void testInitArrayInConstructor() { doTest(); }
   public void testGetterNullityAfterCheck() { doTest(); }
   public void testInferenceNullityMismatch() { doTestWith(insp -> insp.SUGGEST_NULLABLE_ANNOTATIONS = false); }

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/ClassUtils.java

@@ -152,8 +152,9 @@ public final class ClassUtils {
     return aClass.hasModifierProperty(PsiModifier.FINAL) &&
            Arrays.stream(aClass.getAllFields())
              .filter(field -> !field.hasModifierProperty(PsiModifier.STATIC))
-             .map(field -> field.getType())
-             .allMatch(type -> TypeConversionUtil.isPrimitiveAndNotNull(type) || immutableTypes.contains(type.getCanonicalText()));
+             .allMatch(field -> field.hasModifierProperty(PsiModifier.FINAL) &&
+                                (TypeConversionUtil.isPrimitiveAndNotNull(field.getType()) ||
+                                 immutableTypes.contains(field.getType().getCanonicalText())));
   }
 
   public static boolean inSamePackage(@Nullable PsiElement element1, @Nullable PsiElement element2) {