IG: don't warn about unnecessary final on compile-time constants (IDEA-210351)

GitOrigin-RevId: 337f6b6d55eacf3c7b259ffa1f6661527ce57f54

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/style/UnnecessaryFinalOnLocalVariableOrParameterInspection.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2017 Dave Griffith, Bas Leijdekkers
+ * Copyright 2003-2019 Dave Griffith, Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -195,8 +195,9 @@ public class UnnecessaryFinalOnLocalVariableOrParameterInspection extends BaseIn
       check(parameter);
     }
 
-    private boolean isNecessaryFinal(PsiVariable parameter, PsiElement context) {
-      return !PsiUtil.isLanguageLevel8OrHigher(parameter) && VariableAccessUtils.variableIsUsedInInnerClass(parameter, context);
+    private boolean isNecessaryFinal(PsiVariable variable, PsiElement context) {
+      return PsiUtil.isConstantExpression(variable.getInitializer()) ||
+             !PsiUtil.isLanguageLevel8OrHigher(variable) && VariableAccessUtils.variableIsUsedInInnerClass(variable, context);
     }
 
     private void check(PsiParameter parameter) {

plugins/InspectionGadgets/test/com/siyeh/igtest/style/unnecessary_final_on_local_variable_or_parameter/UnnecessaryFinalOnLocalVariableOrParameter.java

@@ -36,4 +36,20 @@ public class UnnecessaryFinalOnLocalVariableOrParameter {
       }
     }
   }
+}
+class Sample {
+
+  public static void main(String[] args) {
+    final int ALPHA_OPAQUE = (short) 0xFFFF; // IDEA suggests to remove final
+    final int ALPHA_TRANSLUCENT = (short) 0; // IDEA suggests to remove final
+
+    int size = 5;
+    short[][] data = {
+      new short[size],
+      new short[size]
+    };
+
+    data[1][1] = ALPHA_TRANSLUCENT;
+    data[1][1] = ALPHA_OPAQUE;
+  }
 }