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Fixing bug 2826119 - False +: DoubleCheckedLocking warning with volatile field

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git-svn-id: https://pmd.svn.sourceforge.net/svnroot/pmd/branches/pmd/4.2.x@6978 51baf565-9d33-0410-a72c-fc3788e3496d
This commit is contained in:
Romain Pelisse
2009-08-15 16:40:53 +00:00
parent 6f427f9fa5
commit 73ebf2603a
3 changed files with 57 additions and 8 deletions
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2
pmd/etc/changelog.txt
View File

@ -6,6 +6,8 @@ Fixed bug 2606609 - False "UnusedImports" positive in package-info.java
Fixed bug 2645268 - ClassCastException in UselessOperationOnImmutable.getDeclaration
Fixed bug 2724653 - AvoidThreadGroup reports false positives
Fixed bug 2835074 - False -: DoubleCheckedLocking with reversed null check
Fixed bug 2826119 - False +: DoubleCheckedLocking warning with volatile field
Correct -benchmark reporting of Rule visits via the RuleChain
Fix issue with Type Resolution incorrectly handling of Classes with same name as a java.lang Class.

30
pmd/regress/test/net/sourceforge/pmd/rules/basic/xml/DoubleCheckedLocking.xml
View File

@ -57,8 +57,8 @@ public class Foo {
</test-code>
<test-code>
<description><![CDATA[
inversed null check -see bug 2835074 False -: DoubleCheckedLocking with reversed null check
2835074 False -: DoubleCheckedLocking with reversed null check
inversed null check
see bug 2835074 False -: DoubleCheckedLocking with reversed null check (1)
]]></description>
<expected-problems>1</expected-problems>
<code><![CDATA[
@ -79,8 +79,8 @@ public class Foo {
</test-code>
<test-code>
<description><![CDATA[
inversed null check -see bug 2835074 False -: DoubleCheckedLocking with reversed null check
2835074 False -: DoubleCheckedLocking with reversed null check
inversed null check
see bug 2835074 False -: DoubleCheckedLocking with reversed null check (2)
]]></description>
<expected-problems>1</expected-problems>
<code><![CDATA[
@ -96,6 +96,28 @@ public class Foo {
}
return baz;
}
}
]]></code>
</test-code>
<test-code>
<description><![CDATA[
Use of volatile keyword
see bug 2826119 - False +: DoubleCheckedLocking warning with volatile field
]]></description>
<expected-problems>0</expected-problems>
<code><![CDATA[
public class Foo {
volatile Object baz;
Object bar() {
if(baz == null) { //baz may be non-null yet not fully created
synchronized(this){
if(null == baz){
baz = new Object();
}
}
}
return baz;
}
}
]]></code>
</test-code>

33
pmd/src/net/sourceforge/pmd/rules/DoubleCheckedLocking.java
View File

@ -3,9 +3,14 @@
*/
package net.sourceforge.pmd.rules;
import java.util.ArrayList;
import java.util.List;
import net.sourceforge.pmd.AbstractJavaRule;
import net.sourceforge.pmd.ast.ASTAssignmentOperator;
import net.sourceforge.pmd.ast.ASTClassOrInterfaceDeclaration;
import net.sourceforge.pmd.ast.ASTCompilationUnit;
import net.sourceforge.pmd.ast.ASTFieldDeclaration;
import net.sourceforge.pmd.ast.ASTIfStatement;
import net.sourceforge.pmd.ast.ASTLiteral;
import net.sourceforge.pmd.ast.ASTMethodDeclaration;
@ -18,11 +23,9 @@ import net.sourceforge.pmd.ast.ASTReturnStatement;
import net.sourceforge.pmd.ast.ASTStatementExpression;
import net.sourceforge.pmd.ast.ASTSynchronizedStatement;
import net.sourceforge.pmd.ast.ASTType;
import net.sourceforge.pmd.ast.ASTVariableDeclaratorId;
import net.sourceforge.pmd.ast.Node;
import java.util.ArrayList;
import java.util.List;
/**
* void method() {
* if(x == null) {
@ -44,6 +47,17 @@ import java.util.List;
*/
public class DoubleCheckedLocking extends AbstractJavaRule {
List<String> volatileFields;
public Object visit(ASTCompilationUnit compilationUnit, Object data) {
if ( volatileFields == null ) {
volatileFields = new ArrayList<String>(0);
} else {
volatileFields.clear();
}
return super.visit(compilationUnit, data);
}
public Object visit(ASTClassOrInterfaceDeclaration node, Object data) {
if (node.isInterface()) {
return data;
@ -51,6 +65,16 @@ public class DoubleCheckedLocking extends AbstractJavaRule {
return super.visit(node, data);
}
public Object visit(ASTFieldDeclaration fieldDeclaration, Object data) {
if ( fieldDeclaration.isVolatile() ) {
List<ASTVariableDeclaratorId> declarators = fieldDeclaration.findChildrenOfType(ASTVariableDeclaratorId.class);
for (ASTVariableDeclaratorId declarator : declarators ) {
this.volatileFields.add(declarator.getImage());
}
}
return super.visit(fieldDeclaration, data);
}
public Object visit(ASTMethodDeclaration node, Object data) {
if (node.getResultType().isVoid()) {
return super.visit(node, data);
@ -76,7 +100,8 @@ public class DoubleCheckedLocking extends AbstractJavaRule {
if (lastChild instanceof ASTPrimaryPrefix) {
returnVariableName = getNameFromPrimaryPrefix((ASTPrimaryPrefix) lastChild);
}
if (returnVariableName == null) {
// With Java5 and volatile keyword, DCL is no longer an issue
if (returnVariableName == null || this.volatileFields.contains(returnVariableName)) {
return super.visit(node, data);
}
List<ASTIfStatement> isl = new ArrayList<ASTIfStatement>();