| /* |
| * Copyright 2009-2013 Bas Leijdekkers |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.siyeh.ig.psiutils; |
| |
| import com.intellij.psi.*; |
| import com.intellij.psi.util.PsiUtil; |
| import org.jetbrains.annotations.NotNull; |
| |
| public class FinalUtils { |
| |
| private FinalUtils() {} |
| |
| public static boolean canBeFinal(@NotNull PsiVariable variable) { |
| final FinalDefiniteAssignment definiteAssignment = new FinalDefiniteAssignment(variable); |
| DefiniteAssignmentUtil.checkVariable(variable, definiteAssignment); |
| return definiteAssignment.isDefinitelyAssigned() && |
| !definiteAssignment.isDefinitelyUnassigned() && // spec? |
| definiteAssignment.canBeFinal() && |
| !isWrittenToOutsideOfConstruction(variable); |
| } |
| |
| private static boolean isWrittenToOutsideOfConstruction(PsiVariable variable) { |
| if (!(variable instanceof PsiField)) { |
| return false; |
| } |
| final PsiField field = (PsiField)variable; |
| final PsiClass containingClass = field.getContainingClass(); |
| if (containingClass == null) { |
| return false; |
| } |
| final PsiClass topLevelClass = PsiUtil.getTopLevelClass(variable); |
| final VariableAssignedVisitor visitor = new VariableAssignedVisitor(field); |
| if (topLevelClass != null && !containingClass.equals(topLevelClass)) { |
| visitor.setExcludedElement(containingClass); |
| topLevelClass.accept(visitor); |
| if (visitor.isAssigned()) { |
| return true; |
| } |
| } |
| if (field.hasModifierProperty(PsiModifier.STATIC)) { |
| for (PsiElement child : containingClass.getChildren()) { |
| if (child instanceof PsiClassInitializer) { |
| final PsiClassInitializer classInitializer = (PsiClassInitializer)child; |
| if (classInitializer.hasModifierProperty(PsiModifier.STATIC)) { |
| continue; |
| } |
| classInitializer.accept(visitor); |
| } |
| else if (child instanceof PsiField) { |
| final PsiField otherField = (PsiField)child; |
| if (otherField.hasModifierProperty(PsiModifier.STATIC)) { |
| continue; |
| } |
| otherField.accept(visitor); |
| } |
| else if (child instanceof PsiMethod || child instanceof PsiClass) { |
| child.accept(visitor); |
| } |
| if (visitor.isAssigned()) { |
| return true; |
| } |
| } |
| } |
| else { |
| for (PsiElement child : containingClass.getChildren()) { |
| if (child instanceof PsiField) { |
| final PsiField otherField = (PsiField)child; |
| if (!otherField.hasModifierProperty(PsiModifier.STATIC)) { |
| continue; |
| } |
| otherField.accept(visitor); |
| } |
| else if (child instanceof PsiClassInitializer) { |
| final PsiClassInitializer classInitializer = (PsiClassInitializer)child; |
| if (!classInitializer.hasModifierProperty(PsiModifier.STATIC)) { |
| continue; |
| } |
| classInitializer.accept(visitor); |
| } |
| else if (child instanceof PsiMethod) { |
| final PsiMethod method = (PsiMethod)child; |
| if (method.isConstructor()) { |
| continue; |
| } |
| method.accept(visitor); |
| } |
| else if (child instanceof PsiClass) { |
| child.accept(visitor); |
| } |
| if (visitor.isAssigned()) { |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| private static class FinalDefiniteAssignment extends DefiniteAssignment { |
| |
| private boolean canBeFinal = true; |
| |
| public FinalDefiniteAssignment(PsiVariable variable) { |
| super(variable); |
| } |
| |
| @Override |
| public void assign(@NotNull PsiReferenceExpression expression, boolean definiteAssignment) { |
| if (!isDefinitelyUnassigned()) { |
| canBeFinal = false; |
| } |
| super.assign(expression, definiteAssignment); |
| } |
| |
| @Override |
| public void valueAccess(PsiReferenceExpression expression) { |
| if (!isDefinitelyAssigned()) { |
| canBeFinal = false; |
| } |
| super.valueAccess(expression); |
| } |
| |
| @Override |
| public boolean stop() { |
| return !canBeFinal; |
| } |
| |
| public boolean canBeFinal() { |
| return canBeFinal; |
| } |
| } |
| } |