| /* |
| * Copyright 2003-2014 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. |
| * 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.switchtoif; |
| |
| import com.intellij.psi.*; |
| import com.intellij.psi.tree.IElementType; |
| import com.intellij.psi.util.PsiTreeUtil; |
| import com.siyeh.ig.psiutils.ControlFlowUtils; |
| import com.siyeh.ig.psiutils.EquivalenceChecker; |
| import com.siyeh.ig.psiutils.SwitchUtils; |
| import com.siyeh.ig.psiutils.SwitchUtils.IfStatementBranch; |
| import com.siyeh.ipp.base.Intention; |
| import com.siyeh.ipp.base.PsiElementPredicate; |
| import org.jetbrains.annotations.NonNls; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| public class ReplaceIfWithSwitchIntention extends Intention { |
| |
| @Override |
| @NotNull |
| public PsiElementPredicate getElementPredicate() { |
| return new IfToSwitchPredicate(); |
| } |
| |
| @Override |
| public void processIntention(@NotNull PsiElement element) { |
| final PsiJavaToken switchToken = (PsiJavaToken)element; |
| PsiIfStatement ifStatement = (PsiIfStatement)switchToken.getParent(); |
| if (ifStatement == null) { |
| return; |
| } |
| boolean breaksNeedRelabeled = false; |
| PsiStatement breakTarget = null; |
| String labelString = ""; |
| if (ControlFlowUtils.statementContainsNakedBreak(ifStatement)) { |
| breakTarget = PsiTreeUtil.getParentOfType(ifStatement, PsiLoopStatement.class, PsiSwitchStatement.class); |
| if (breakTarget != null) { |
| final PsiElement parent = breakTarget.getParent(); |
| if (parent instanceof PsiLabeledStatement) { |
| final PsiLabeledStatement labeledStatement = (PsiLabeledStatement)parent; |
| labelString = labeledStatement.getLabelIdentifier().getText(); |
| breakTarget = labeledStatement; |
| breaksNeedRelabeled = true; |
| } |
| else { |
| labelString = SwitchUtils.findUniqueLabelName(ifStatement, "label"); |
| breaksNeedRelabeled = true; |
| } |
| } |
| } |
| final PsiIfStatement statementToReplace = ifStatement; |
| final PsiExpression switchExpression = SwitchUtils.getSwitchExpression(ifStatement, 0); |
| if (switchExpression == null) { |
| return; |
| } |
| final List<IfStatementBranch> branches = new ArrayList<IfStatementBranch>(20); |
| while (true) { |
| final PsiExpression condition = ifStatement.getCondition(); |
| final PsiStatement thenBranch = ifStatement.getThenBranch(); |
| final IfStatementBranch ifBranch = new IfStatementBranch(thenBranch, false); |
| extractCaseExpressions(condition, switchExpression, ifBranch); |
| if (!branches.isEmpty()) { |
| extractIfComments(ifStatement, ifBranch); |
| } |
| extractStatementComments(thenBranch, ifBranch); |
| branches.add(ifBranch); |
| final PsiStatement elseBranch = ifStatement.getElseBranch(); |
| if (elseBranch instanceof PsiIfStatement) { |
| ifStatement = (PsiIfStatement)elseBranch; |
| } |
| else if (elseBranch == null) { |
| break; |
| } |
| else { |
| final IfStatementBranch elseIfBranch = new IfStatementBranch(elseBranch, true); |
| final PsiKeyword elseKeyword = ifStatement.getElseElement(); |
| extractIfComments(elseKeyword, elseIfBranch); |
| extractStatementComments(elseBranch, elseIfBranch); |
| branches.add(elseIfBranch); |
| break; |
| } |
| } |
| |
| @NonNls final StringBuilder switchStatementText = new StringBuilder(); |
| switchStatementText.append("switch(").append(switchExpression.getText()).append("){"); |
| final PsiType type = switchExpression.getType(); |
| final boolean castToInt = type != null && type.equalsToText(CommonClassNames.JAVA_LANG_INTEGER); |
| for (IfStatementBranch branch : branches) { |
| boolean hasConflicts = false; |
| for (IfStatementBranch testBranch : branches) { |
| if (branch == testBranch) { |
| continue; |
| } |
| if (branch.topLevelDeclarationsConflictWith(testBranch)) { |
| hasConflicts = true; |
| } |
| } |
| dumpBranch(branch, castToInt, hasConflicts, breaksNeedRelabeled, labelString, switchStatementText); |
| } |
| switchStatementText.append('}'); |
| final JavaPsiFacade psiFacade = JavaPsiFacade.getInstance(element.getProject()); |
| final PsiElementFactory factory = psiFacade.getElementFactory(); |
| if (breaksNeedRelabeled) { |
| final StringBuilder out = new StringBuilder(); |
| if (!(breakTarget instanceof PsiLabeledStatement)) { |
| out.append(labelString).append(':'); |
| } |
| termReplace(breakTarget, statementToReplace, switchStatementText, out); |
| final String newStatementText = out.toString(); |
| final PsiStatement newStatement = factory.createStatementFromText(newStatementText, element); |
| breakTarget.replace(newStatement); |
| } |
| else { |
| final PsiStatement newStatement = factory.createStatementFromText(switchStatementText.toString(), element); |
| statementToReplace.replace(newStatement); |
| } |
| } |
| |
| @Nullable |
| public static <T extends PsiElement> T getPrevSiblingOfType(@Nullable PsiElement element, @NotNull Class<T> aClass, |
| @NotNull Class<? extends PsiElement>... stopAt) { |
| if (element == null) { |
| return null; |
| } |
| PsiElement sibling = element.getPrevSibling(); |
| while (sibling != null && !aClass.isInstance(sibling)) { |
| for (Class<? extends PsiElement> stopClass : stopAt) { |
| if (stopClass.isInstance(sibling)) { |
| return null; |
| } |
| } |
| sibling = sibling.getPrevSibling(); |
| } |
| return (T)sibling; |
| } |
| |
| private static void extractIfComments(PsiElement element, IfStatementBranch out) { |
| PsiComment comment = getPrevSiblingOfType(element, PsiComment.class, PsiStatement.class); |
| while (comment != null) { |
| final PsiElement sibling = comment.getPrevSibling(); |
| final String commentText; |
| if (sibling instanceof PsiWhiteSpace) { |
| final String whiteSpaceText = sibling.getText(); |
| if (whiteSpaceText.startsWith("\n")) { |
| commentText = whiteSpaceText.substring(1) + comment.getText(); |
| } |
| else { |
| commentText = comment.getText(); |
| } |
| } |
| else { |
| commentText = comment.getText(); |
| } |
| out.addComment(commentText); |
| comment = getPrevSiblingOfType(comment, PsiComment.class, PsiStatement.class); |
| } |
| } |
| |
| private static void extractStatementComments(PsiElement element, IfStatementBranch out) { |
| PsiComment comment = getPrevSiblingOfType(element, PsiComment.class, PsiStatement.class, PsiKeyword.class); |
| while (comment != null) { |
| final PsiElement sibling = comment.getPrevSibling(); |
| final String commentText; |
| if (sibling instanceof PsiWhiteSpace) { |
| final String whiteSpaceText = sibling.getText(); |
| if (whiteSpaceText.startsWith("\n")) { |
| commentText = whiteSpaceText.substring(1) + comment.getText(); |
| } |
| else { |
| commentText = comment.getText(); |
| } |
| } |
| else { |
| commentText = comment.getText(); |
| } |
| out.addStatementComment(commentText); |
| comment = getPrevSiblingOfType(comment, PsiComment.class, PsiStatement.class, PsiKeyword.class); |
| } |
| } |
| |
| private static void termReplace(PsiElement target, PsiElement replace, StringBuilder stringToReplaceWith, StringBuilder out) { |
| if (target.equals(replace)) { |
| out.append(stringToReplaceWith); |
| } |
| else if (target.getChildren().length == 0) { |
| out.append(target.getText()); |
| } |
| else { |
| final PsiElement[] children = target.getChildren(); |
| for (final PsiElement child : children) { |
| termReplace(child, replace, stringToReplaceWith, out); |
| } |
| } |
| } |
| |
| private static void extractCaseExpressions(PsiExpression expression, PsiExpression switchExpression, IfStatementBranch values) { |
| if (expression instanceof PsiMethodCallExpression) { |
| final PsiMethodCallExpression methodCallExpression = (PsiMethodCallExpression)expression; |
| final PsiExpressionList argumentList = methodCallExpression.getArgumentList(); |
| final PsiExpression[] arguments = argumentList.getExpressions(); |
| final PsiExpression argument = arguments[0]; |
| final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression(); |
| final PsiExpression qualifierExpression = methodExpression.getQualifierExpression(); |
| if (EquivalenceChecker.expressionsAreEquivalent(switchExpression, argument)) { |
| values.addCaseExpression(qualifierExpression); |
| } |
| else { |
| values.addCaseExpression(argument); |
| } |
| } |
| else if (expression instanceof PsiPolyadicExpression) { |
| final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression)expression; |
| final PsiExpression[] operands = polyadicExpression.getOperands(); |
| final IElementType tokenType = polyadicExpression.getOperationTokenType(); |
| if (JavaTokenType.OROR.equals(tokenType)) { |
| for (PsiExpression operand : operands) { |
| extractCaseExpressions(operand, switchExpression, values); |
| } |
| } |
| else if (JavaTokenType.EQEQ.equals(tokenType) && operands.length == 2) { |
| final PsiExpression lhs = operands[0]; |
| final PsiExpression rhs = operands[1]; |
| if (EquivalenceChecker.expressionsAreEquivalent(switchExpression, rhs)) { |
| values.addCaseExpression(lhs); |
| } |
| else if (EquivalenceChecker.expressionsAreEquivalent(switchExpression, lhs)){ |
| values.addCaseExpression(rhs); |
| } |
| } |
| } |
| else if (expression instanceof PsiParenthesizedExpression) { |
| final PsiParenthesizedExpression parenthesizedExpression = (PsiParenthesizedExpression)expression; |
| final PsiExpression contents = parenthesizedExpression.getExpression(); |
| extractCaseExpressions(contents, switchExpression, values); |
| } |
| } |
| |
| private static void dumpBranch(IfStatementBranch branch, boolean castToInt, boolean wrap, boolean renameBreaks, String breakLabelName, |
| @NonNls StringBuilder switchStatementText) { |
| dumpComments(branch.getComments(), switchStatementText); |
| if (branch.isElse()) { |
| switchStatementText.append("default: "); |
| } |
| else { |
| for (PsiExpression caseExpression : branch.getCaseExpressions()) { |
| switchStatementText.append("case ").append(getCaseLabelText(caseExpression, castToInt)).append(": "); |
| } |
| } |
| dumpComments(branch.getStatementComments(), switchStatementText); |
| dumpBody(branch.getStatement(), wrap, renameBreaks, breakLabelName, switchStatementText); |
| } |
| |
| @NonNls |
| private static String getCaseLabelText(PsiExpression expression, boolean castToInt) { |
| if (expression instanceof PsiReferenceExpression) { |
| final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)expression; |
| final PsiElement target = referenceExpression.resolve(); |
| if (target instanceof PsiEnumConstant) { |
| final PsiEnumConstant enumConstant = (PsiEnumConstant)target; |
| return enumConstant.getName(); |
| } |
| } |
| if (castToInt) { |
| final PsiType type = expression.getType(); |
| if (!PsiType.INT.equals(type)) { |
| /* |
| because |
| Integer a = 1; |
| switch (a) { |
| case (byte)7: |
| } |
| does not compile with javac (but does with Eclipse) |
| */ |
| return "(int)" + expression.getText(); |
| } |
| } |
| return expression.getText(); |
| } |
| |
| private static void dumpComments(List<String> comments, StringBuilder switchStatementText) { |
| if (comments.isEmpty()) { |
| return; |
| } |
| switchStatementText.append('\n'); |
| for (String comment : comments) { |
| switchStatementText.append(comment).append('\n'); |
| } |
| } |
| |
| private static void dumpBody(PsiStatement bodyStatement, boolean wrap, boolean renameBreaks, String breakLabelName, |
| @NonNls StringBuilder switchStatementText) { |
| if (wrap) { |
| switchStatementText.append('{'); |
| } |
| if (bodyStatement instanceof PsiBlockStatement) { |
| final PsiCodeBlock codeBlock = ((PsiBlockStatement)bodyStatement).getCodeBlock(); |
| final PsiElement[] children = codeBlock.getChildren(); |
| //skip the first and last members, to unwrap the block |
| for (int i = 1; i < children.length - 1; i++) { |
| final PsiElement child = children[i]; |
| appendElement(child, renameBreaks, breakLabelName, switchStatementText); |
| } |
| } |
| else { |
| appendElement(bodyStatement, renameBreaks, breakLabelName, switchStatementText); |
| } |
| if (ControlFlowUtils.statementMayCompleteNormally(bodyStatement)) { |
| switchStatementText.append("break;"); |
| } |
| if (wrap) { |
| switchStatementText.append('}'); |
| } |
| } |
| |
| private static void appendElement(PsiElement element, boolean renameBreakElements, String breakLabelString, |
| @NonNls StringBuilder switchStatementText) { |
| final String text = element.getText(); |
| if (!renameBreakElements) { |
| switchStatementText.append(text); |
| } |
| else if (element instanceof PsiBreakStatement) { |
| final PsiBreakStatement breakStatement = (PsiBreakStatement)element; |
| final PsiIdentifier identifier = breakStatement.getLabelIdentifier(); |
| if (identifier == null) { |
| switchStatementText.append("break ").append(breakLabelString).append(';'); |
| } |
| else { |
| switchStatementText.append(text); |
| } |
| } |
| else if (element instanceof PsiBlockStatement || element instanceof PsiCodeBlock || element instanceof PsiIfStatement) { |
| final PsiElement[] children = element.getChildren(); |
| for (final PsiElement child : children) { |
| appendElement(child, renameBreakElements, breakLabelString, switchStatementText); |
| } |
| } |
| else { |
| switchStatementText.append(text); |
| } |
| final PsiElement lastChild = element.getLastChild(); |
| if (isEndOfLineComment(lastChild)) { |
| switchStatementText.append('\n'); |
| } |
| } |
| |
| private static boolean isEndOfLineComment(PsiElement element) { |
| if (!(element instanceof PsiComment)) { |
| return false; |
| } |
| final PsiComment comment = (PsiComment)element; |
| final IElementType tokenType = comment.getTokenType(); |
| return JavaTokenType.END_OF_LINE_COMMENT.equals(tokenType); |
| } |
| } |
