| /* |
| * Copyright 2000-2014 JetBrains s.r.o. |
| * |
| * 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.ipp.asserttoif; |
| |
| import com.intellij.codeInsight.AnnotationUtil; |
| import com.intellij.codeInsight.NullableNotNullManager; |
| import com.intellij.psi.*; |
| import com.intellij.psi.tree.IElementType; |
| import com.intellij.psi.util.PsiTreeUtil; |
| import com.intellij.psi.util.PsiUtil; |
| import com.siyeh.ig.PsiReplacementUtil; |
| import com.siyeh.ig.psiutils.ClassUtils; |
| import com.siyeh.ig.psiutils.ParenthesesUtils; |
| import com.siyeh.ig.psiutils.VariableAccessUtils; |
| import com.siyeh.ipp.base.Intention; |
| import com.siyeh.ipp.base.PsiElementPredicate; |
| import org.jetbrains.annotations.NotNull; |
| |
| import java.util.List; |
| |
| /** |
| * @author Bas Leijdekkers |
| */ |
| public class ObjectsRequireNonNullIntention extends Intention { |
| |
| @NotNull |
| @Override |
| protected PsiElementPredicate getElementPredicate() { |
| return new NullCheckedAssignmentPredicate(); |
| } |
| |
| @Override |
| protected void processIntention(@NotNull PsiElement element) { |
| if (!(element instanceof PsiReferenceExpression)) { |
| return; |
| } |
| final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)element; |
| final PsiElement target = referenceExpression.resolve(); |
| if (!(target instanceof PsiVariable)) { |
| return; |
| } |
| final PsiVariable variable = (PsiVariable)target; |
| final List<String> notNulls = NullableNotNullManager.getInstance(element.getProject()).getNotNulls(); |
| final PsiAnnotation annotation = AnnotationUtil.findAnnotation(variable, notNulls); |
| if (annotation != null) { |
| annotation.delete(); |
| } else { |
| final PsiStatement referenceStatement = PsiTreeUtil.getParentOfType(referenceExpression, PsiStatement.class); |
| if (referenceStatement == null) { |
| return; |
| } |
| final PsiElement parent = referenceStatement.getParent(); |
| if (!(parent instanceof PsiCodeBlock)) { |
| return; |
| } |
| final PsiCodeBlock codeBlock = (PsiCodeBlock)parent; |
| final PsiStatement[] statements = codeBlock.getStatements(); |
| PsiStatement statementToDelete = null; |
| for (PsiStatement statement : statements) { |
| if (statement == referenceStatement) { |
| break; |
| } |
| if (NullCheckedAssignmentPredicate.isNotNullAssertion(statement, variable) || |
| NullCheckedAssignmentPredicate.isIfStatementNullCheck(statement, variable)) { |
| statementToDelete = statement; |
| break; |
| } |
| } |
| if (statementToDelete == null) { |
| return; |
| } |
| statementToDelete.delete(); |
| } |
| PsiReplacementUtil |
| .replaceExpressionAndShorten(referenceExpression, "java.util.Objects.requireNonNull(" + referenceExpression.getText() + ")"); |
| } |
| |
| private static class NullCheckedAssignmentPredicate implements PsiElementPredicate { |
| |
| @Override |
| public boolean satisfiedBy(PsiElement element) { |
| if (!PsiUtil.isLanguageLevel7OrHigher(element)) { |
| return false; |
| } |
| if (!(element instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)element; |
| if (PsiUtil.isAccessedForWriting(referenceExpression)) { |
| return false; |
| } |
| final PsiElement target = referenceExpression.resolve(); |
| if (!(target instanceof PsiVariable)) { |
| return false; |
| } |
| final PsiVariable variable = (PsiVariable)target; |
| if (ClassUtils.findClass("java.util.Objects", element) == null) { |
| return false; |
| } |
| if (NullableNotNullManager.isNotNull(variable)) { |
| return true; |
| } |
| final PsiStatement referenceStatement = PsiTreeUtil.getParentOfType(referenceExpression, PsiStatement.class); |
| final PsiElement parent = referenceStatement != null ? referenceStatement.getParent() : null; |
| if (!(parent instanceof PsiCodeBlock)) { |
| return false; |
| } |
| final PsiCodeBlock codeBlock = (PsiCodeBlock)parent; |
| final PsiStatement[] statements = codeBlock.getStatements(); |
| for (PsiStatement statement : statements) { |
| if (statement == referenceStatement) { |
| return false; |
| } |
| if (isNotNullAssertion(statement, variable) || isIfStatementNullCheck(statement, variable)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| private static boolean isIfStatementNullCheck(PsiStatement statement, @NotNull PsiVariable variable) { |
| if (!(statement instanceof PsiIfStatement)) { |
| return false; |
| } |
| final PsiIfStatement ifStatement = (PsiIfStatement)statement; |
| final PsiStatement elseBranch = ifStatement.getElseBranch(); |
| if (elseBranch != null) { |
| return false; |
| } |
| final PsiStatement thenBranch = ifStatement.getThenBranch(); |
| if (!IfStatementPredicate.isSimpleThrowStatement(thenBranch)) { |
| return false; |
| } |
| final PsiExpression condition = ifStatement.getCondition(); |
| return isNullComparison(condition, variable, true); |
| } |
| |
| private static boolean isNotNullAssertion(PsiStatement statement, @NotNull PsiVariable variable) { |
| if (!(statement instanceof PsiAssertStatement)) { |
| return false; |
| } |
| final PsiAssertStatement assertStatement = (PsiAssertStatement)statement; |
| final PsiExpression condition = assertStatement.getAssertCondition(); |
| return isNullComparison(condition, variable, false); |
| } |
| |
| private static boolean isNullComparison(PsiExpression expression, @NotNull PsiVariable variable, boolean equal) { |
| expression = ParenthesesUtils.stripParentheses(expression); |
| if (!(expression instanceof PsiBinaryExpression)) { |
| return false; |
| } |
| final PsiBinaryExpression binaryExpression = (PsiBinaryExpression)expression; |
| final IElementType tokenType = binaryExpression.getOperationTokenType(); |
| if (equal) { |
| if (!JavaTokenType.EQEQ.equals(tokenType)) { |
| return false; |
| } |
| } |
| else { |
| if (!JavaTokenType.NE.equals(tokenType)) { |
| return false; |
| } |
| } |
| final PsiExpression lhs = binaryExpression.getLOperand(); |
| final PsiExpression rhs = binaryExpression.getROperand(); |
| if (rhs == null) { |
| return false; |
| } |
| return PsiType.NULL.equals(rhs.getType()) && VariableAccessUtils.evaluatesToVariable(lhs, variable) || |
| PsiType.NULL.equals(lhs.getType()) && VariableAccessUtils.evaluatesToVariable(rhs, variable); |
| } |
| } |
| } |