/*
* SonarQube Java
* Copyright (C) 2012-2016 SonarSource SA
* mailto:contact AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.java.checks;
import com.google.common.collect.HashMultiset;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Multiset;
import com.google.common.collect.Multiset.Entry;
import org.sonar.check.Rule;
import org.sonar.java.RspecKey;
import org.sonar.plugins.java.api.IssuableSubscriptionVisitor;
import org.sonar.plugins.java.api.tree.AssertStatementTree;
import org.sonar.plugins.java.api.tree.BaseTreeVisitor;
import org.sonar.plugins.java.api.tree.BlockTree;
import org.sonar.plugins.java.api.tree.BreakStatementTree;
import org.sonar.plugins.java.api.tree.ClassTree;
import org.sonar.plugins.java.api.tree.ContinueStatementTree;
import org.sonar.plugins.java.api.tree.DoWhileStatementTree;
import org.sonar.plugins.java.api.tree.ExpressionStatementTree;
import org.sonar.plugins.java.api.tree.ForEachStatement;
import org.sonar.plugins.java.api.tree.ForStatementTree;
import org.sonar.plugins.java.api.tree.IfStatementTree;
import org.sonar.plugins.java.api.tree.MethodTree;
import org.sonar.plugins.java.api.tree.ReturnStatementTree;
import org.sonar.plugins.java.api.tree.StatementTree;
import org.sonar.plugins.java.api.tree.SwitchStatementTree;
import org.sonar.plugins.java.api.tree.SynchronizedStatementTree;
import org.sonar.plugins.java.api.tree.SyntaxToken;
import org.sonar.plugins.java.api.tree.ThrowStatementTree;
import org.sonar.plugins.java.api.tree.Tree;
import org.sonar.plugins.java.api.tree.Tree.Kind;
import org.sonar.plugins.java.api.tree.TryStatementTree;
import org.sonar.plugins.java.api.tree.VariableTree;
import org.sonar.plugins.java.api.tree.WhileStatementTree;
import java.util.List;
@Rule(key = "S00122")
@RspecKey("S122")
public class TooManyStatementsPerLineCheck extends IssuableSubscriptionVisitor {
@Override
public List<Kind> nodesToVisit() {
return ImmutableList.of(Tree.Kind.METHOD, Tree.Kind.CONSTRUCTOR, Tree.Kind.STATIC_INITIALIZER);
}
@Override
public void visitNode(Tree tree) {
BlockTree block;
if (tree.is(Tree.Kind.STATIC_INITIALIZER)) {
block = (BlockTree) tree;
} else {
block = ((MethodTree) tree).block();
}
if (block != null) {
StatementVisitor visitor = new StatementVisitor();
block.accept(visitor);
for (Entry<Integer> entry : visitor.statementsPerLine.entrySet()) {
int count = entry.getCount();
if (count > 1) {
addIssue(entry.getElement(), "At most one statement is allowed per line, but " + count + " statements were found on this line.");
}
}
}
}
private static class StatementVisitor extends BaseTreeVisitor {
private final Multiset<Integer> statementsPerLine = HashMultiset.create();
@Override
public void visitClass(ClassTree tree) {
// do nothing, as inner class will be visited later
}
@Override
public void visitAssertStatement(AssertStatementTree tree) {
addLines(tree.assertKeyword(), tree.semicolonToken());
}
@Override
public void visitBreakStatement(BreakStatementTree tree) {
addLines(tree.breakKeyword(), tree.semicolonToken());
}
@Override
public void visitContinueStatement(ContinueStatementTree tree) {
addLines(tree.continueKeyword(), tree.semicolonToken());
}
@Override
public void visitReturnStatement(ReturnStatementTree tree) {
addLines(tree.returnKeyword(), tree.semicolonToken());
}
@Override
public void visitThrowStatement(ThrowStatementTree tree) {
addLines(tree.throwKeyword(), tree.semicolonToken());
}
@Override
public void visitExpressionStatement(ExpressionStatementTree tree) {
SyntaxToken firstToken = tree.firstToken();
if (firstToken != null) {
addLines(firstToken, tree.semicolonToken());
} else {
addLine(tree.semicolonToken());
}
}
@Override
public void visitIfStatement(IfStatementTree tree) {
addLine(tree.ifKeyword());
StatementTree thenStatement = tree.thenStatement();
StatementTree elseStatement = tree.elseStatement();
scan(thenStatement);
scan(elseStatement);
if (elseStatement == null) {
addLineOfCloseBrace(tree.ifKeyword(), thenStatement);
} else {
addLineOfCloseBrace(tree.ifKeyword(), elseStatement);
}
}
private void addLineOfCloseBrace(SyntaxToken startToken, StatementTree tree) {
if (tree.is(Tree.Kind.BLOCK)) {
SyntaxToken closeBraceToken = ((BlockTree) tree).closeBraceToken();
if (startToken.line() != closeBraceToken.line() && !statementsPerLine.contains(closeBraceToken.line())) {
addLine(closeBraceToken);
}
}
}
@Override
public void visitSynchronizedStatement(SynchronizedStatementTree tree) {
addLine(tree.synchronizedKeyword());
addLineOfCloseBrace(tree.synchronizedKeyword(), tree.block());
scan(tree.block());
}
@Override
public void visitSwitchStatement(SwitchStatementTree tree) {
addLines(tree.switchKeyword(), tree.openBraceToken());
scan(tree.cases());
addLine(tree.closeBraceToken());
}
@Override
public void visitVariable(VariableTree tree) {
SyntaxToken endToken = tree.endToken();
if (endToken != null && ";".equals(endToken.text())) {
addLine(endToken);
}
}
@Override
public void visitWhileStatement(WhileStatementTree tree) {
// do not scan the condition
addLines(tree.whileKeyword(), tree.closeParenToken());
addLineOfCloseBrace(tree.whileKeyword(), tree.statement());
scan(tree.statement());
}
@Override
public void visitDoWhileStatement(DoWhileStatementTree tree) {
// do not scan the condition
addLine(tree.doKeyword());
if (tree.doKeyword().line() != tree.whileKeyword().line()) {
addLines(tree.whileKeyword(), tree.semicolonToken());
}
scan(tree.statement());
}
@Override
public void visitForStatement(ForStatementTree tree) {
// do not scan the initializer, updater and condition
addLines(tree.forKeyword(), tree.closeParenToken());
addLineOfCloseBrace(tree.forKeyword(), tree.statement());
scan(tree.statement());
}
@Override
public void visitForEachStatement(ForEachStatement tree) {
// do not scan the variable and expression
addLines(tree.forKeyword(), tree.closeParenToken());
addLineOfCloseBrace(tree.forKeyword(), tree.statement());
scan(tree.statement());
}
@Override
public void visitTryStatement(TryStatementTree tree) {
// do not scan resources
if (tree.resources().isEmpty()) {
addLine(tree.tryKeyword());
} else {
addLines(tree.tryKeyword(), tree.closeParenToken());
}
scan(tree.block());
scan(tree.catches());
if (tree.finallyKeyword() != null) {
addLine(tree.finallyKeyword());
}
scan(tree.finallyBlock());
}
private void addLine(SyntaxToken token) {
statementsPerLine.add(token.line());
}
private void addLines(SyntaxToken startToken, SyntaxToken endToken) {
addLine(startToken);
if (startToken.line() != endToken.line()) {
addLine(endToken);
}
}
}
}