Examples with ThisNode org.checkerframework.dataflow.cfg.node.ThisNode used on opensource projects

Example 1 with ThisNode

use of org.checkerframework.dataflow.cfg.node.ThisNode in project checker-framework by typetools.

the class CFGTranslationPhaseOne method visitAssignment.

@Override
public Node visitAssignment(AssignmentTree tree, Void p) {
    // see JLS 15.26.1
    AssignmentNode assignmentNode;
    ExpressionTree variable = tree.getVariable();
    TypeMirror varType = TreeUtils.typeOf(variable);
    // case 1: lhs is field access
    if (TreeUtils.isFieldAccess(variable)) {
        // visit receiver
        Node receiver = getReceiver(variable);
        // visit expression
        Node expression = scan(tree.getExpression(), p);
        expression = assignConvert(expression, varType);
        // visit field access (throws null-pointer exception)
        FieldAccessNode target = new FieldAccessNode(variable, receiver);
        target.setLValue();
        Element element = TreeUtils.elementFromUse(variable);
        if (ElementUtils.isStatic(element) || receiver instanceof ThisNode) {
            // No NullPointerException can be thrown, use normal node
            extendWithNode(target);
        } else {
            extendWithNodeWithException(target, nullPointerExceptionType);
        }
        // add assignment node
        assignmentNode = new AssignmentNode(tree, target, expression);
        extendWithNode(assignmentNode);
    } else // case 2: lhs is not a field access
    {
        Node target = scan(variable, p);
        target.setLValue();
        assignmentNode = translateAssignment(tree, target, tree.getExpression());
    }
    return assignmentNode;
}

Example 2 with ThisNode

use of org.checkerframework.dataflow.cfg.node.ThisNode in project checker-framework by typetools.

the class InitializationTransfer method initializedFieldsAfterCall.

/**
 * Returns the fields that can safely be considered initialized after the method call {@code
 * node}.
 *
 * @param node a method call
 * @return the fields that are initialized after the method call
 */
protected List<VariableElement> initializedFieldsAfterCall(MethodInvocationNode node) {
    List<VariableElement> result = new ArrayList<>();
    MethodInvocationTree tree = node.getTree();
    ExecutableElement method = TreeUtils.elementFromUse(tree);
    boolean isConstructor = method.getSimpleName().contentEquals("<init>");
    Node receiver = node.getTarget().getReceiver();
    String methodString = tree.getMethodSelect().toString();
    // invariant fields are guaranteed to be initialized.
    if (isConstructor && receiver instanceof ThisNode && methodString.equals("this")) {
        ClassTree clazz = TreePathUtil.enclosingClass(analysis.getTypeFactory().getPath(tree));
        TypeElement clazzElem = TreeUtils.elementFromDeclaration(clazz);
        markInvariantFieldsAsInitialized(result, clazzElem);
    }
    // invariant fields of any super class are guaranteed to be initialized.
    if (isConstructor && receiver instanceof ThisNode && methodString.equals("super")) {
        ClassTree clazz = TreePathUtil.enclosingClass(analysis.getTypeFactory().getPath(tree));
        TypeElement clazzElem = TreeUtils.elementFromDeclaration(clazz);
        TypeMirror superClass = clazzElem.getSuperclass();
        while (superClass != null && superClass.getKind() != TypeKind.NONE) {
            clazzElem = (TypeElement) analysis.getTypes().asElement(superClass);
            superClass = clazzElem.getSuperclass();
            markInvariantFieldsAsInitialized(result, clazzElem);
        }
    }
    return result;
}

Example 3 with ThisNode

use of org.checkerframework.dataflow.cfg.node.ThisNode in project checker-framework by typetools.

the class InitializationTransfer method visitFieldAccess.

/**
 * If an invariant field is initialized and has the invariant annotation, than it has at least the
 * invariant annotation. Note that only fields of the 'this' receiver are tracked for
 * initialization.
 */
@Override
public TransferResult<V, S> visitFieldAccess(FieldAccessNode n, TransferInput<V, S> p) {
    TransferResult<V, S> result = super.visitFieldAccess(n, p);
    assert !result.containsTwoStores();
    S store = result.getRegularStore();
    if (store.isFieldInitialized(n.getElement()) && n.getReceiver() instanceof ThisNode) {
        AnnotatedTypeMirror fieldAnno = analysis.getTypeFactory().getAnnotatedType(n.getElement());
        // such as @NonNull.
        if (fieldAnno.hasAnnotation(atypeFactory.getFieldInvariantAnnotation())) {
            AnnotationMirror inv = atypeFactory.getFieldInvariantAnnotation();
            V oldResultValue = result.getResultValue();
            V refinedResultValue = analysis.createSingleAnnotationValue(inv, oldResultValue.getUnderlyingType());
            V newResultValue = refinedResultValue.mostSpecific(oldResultValue, null);
            result.setResultValue(newResultValue);
        }
    }
    return result;
}

Example 4 with ThisNode

use of org.checkerframework.dataflow.cfg.node.ThisNode in project checker-framework by typetools.

the class JavaExpression method fromNode.

/**
 * We ignore operations such as widening and narrowing when computing the internal representation.
 *
 * @param receiverNode a node to convert to a JavaExpression
 * @return the internal representation of the given node. Might contain {@link Unknown}.
 */
public static JavaExpression fromNode(Node receiverNode) {
    JavaExpression result = null;
    if (receiverNode instanceof FieldAccessNode) {
        result = fromNodeFieldAccess((FieldAccessNode) receiverNode);
    } else if (receiverNode instanceof ExplicitThisNode) {
        result = new ThisReference(receiverNode.getType());
    } else if (receiverNode instanceof ThisNode) {
        result = new ThisReference(receiverNode.getType());
    } else if (receiverNode instanceof SuperNode) {
        result = new ThisReference(receiverNode.getType());
    } else if (receiverNode instanceof LocalVariableNode) {
        LocalVariableNode lv = (LocalVariableNode) receiverNode;
        result = new LocalVariable(lv);
    } else if (receiverNode instanceof ArrayAccessNode) {
        ArrayAccessNode a = (ArrayAccessNode) receiverNode;
        result = fromArrayAccess(a);
    } else if (receiverNode instanceof StringConversionNode) {
        // ignore string conversion
        return fromNode(((StringConversionNode) receiverNode).getOperand());
    } else if (receiverNode instanceof WideningConversionNode) {
        // ignore widening
        return fromNode(((WideningConversionNode) receiverNode).getOperand());
    } else if (receiverNode instanceof NarrowingConversionNode) {
        // ignore narrowing
        return fromNode(((NarrowingConversionNode) receiverNode).getOperand());
    } else if (receiverNode instanceof UnaryOperationNode) {
        UnaryOperationNode uopn = (UnaryOperationNode) receiverNode;
        return new UnaryOperation(uopn, fromNode(uopn.getOperand()));
    } else if (receiverNode instanceof BinaryOperationNode) {
        BinaryOperationNode bopn = (BinaryOperationNode) receiverNode;
        return new BinaryOperation(bopn, fromNode(bopn.getLeftOperand()), fromNode(bopn.getRightOperand()));
    } else if (receiverNode instanceof ClassNameNode) {
        ClassNameNode cn = (ClassNameNode) receiverNode;
        result = new ClassName(cn.getType());
    } else if (receiverNode instanceof ValueLiteralNode) {
        ValueLiteralNode vn = (ValueLiteralNode) receiverNode;
        result = new ValueLiteral(vn.getType(), vn);
    } else if (receiverNode instanceof ArrayCreationNode) {
        ArrayCreationNode an = (ArrayCreationNode) receiverNode;
        List<@Nullable JavaExpression> dimensions = CollectionsPlume.mapList(JavaExpression::fromNode, an.getDimensions());
        List<JavaExpression> initializers = CollectionsPlume.mapList(JavaExpression::fromNode, an.getInitializers());
        result = new ArrayCreation(an.getType(), dimensions, initializers);
    } else if (receiverNode instanceof MethodInvocationNode) {
        MethodInvocationNode mn = (MethodInvocationNode) receiverNode;
        MethodInvocationTree t = mn.getTree();
        if (t == null) {
            throw new BugInCF("Unexpected null tree for node: " + mn);
        }
        assert TreeUtils.isUseOfElement(t) : "@AssumeAssertion(nullness): tree kind";
        ExecutableElement invokedMethod = TreeUtils.elementFromUse(t);
        // Note that the method might be nondeterministic.
        List<JavaExpression> parameters = CollectionsPlume.mapList(JavaExpression::fromNode, mn.getArguments());
        JavaExpression methodReceiver;
        if (ElementUtils.isStatic(invokedMethod)) {
            methodReceiver = new ClassName(mn.getTarget().getReceiver().getType());
        } else {
            methodReceiver = fromNode(mn.getTarget().getReceiver());
        }
        result = new MethodCall(mn.getType(), invokedMethod, methodReceiver, parameters);
    }
    if (result == null) {
        result = new Unknown(receiverNode);
    }
    return result;
}

Example 5 with ThisNode

use of org.checkerframework.dataflow.cfg.node.ThisNode in project checker-framework by typetools.

the class CFGTranslationPhaseOne method visitMethodInvocation.

@Override
public MethodInvocationNode visitMethodInvocation(MethodInvocationTree tree, Void p) {
    // see JLS 15.12.4
    // First, compute the receiver, if any (15.12.4.1).
    // Second, evaluate the actual arguments, left to right and possibly some arguments are stored
    // into an array for variable arguments calls (15.12.4.2).
    // Third, test the receiver, if any, for nullness (15.12.4.4).
    // Fourth, convert the arguments to the type of the formal parameters (15.12.4.5).
    // Fifth, if the method is synchronized, lock the receiving object or class (15.12.4.5).
    ExecutableElement method = TreeUtils.elementFromUse(tree);
    if (method == null) {
        // The method wasn't found, e.g. because of a compilation error.
        return null;
    }
    ExpressionTree methodSelect = tree.getMethodSelect();
    assert TreeUtils.isMethodAccess(methodSelect) : "Expected a method access, but got: " + methodSelect;
    List<? extends ExpressionTree> actualExprs = tree.getArguments();
    // Look up method to invoke and possibly throw NullPointerException
    Node receiver = getReceiver(methodSelect);
    MethodAccessNode target = new MethodAccessNode(methodSelect, receiver);
    ExecutableElement element = TreeUtils.elementFromUse(tree);
    if (ElementUtils.isStatic(element) || receiver instanceof ThisNode) {
        // No NullPointerException can be thrown, use normal node
        extendWithNode(target);
    } else {
        extendWithNodeWithException(target, nullPointerExceptionType);
    }
    List<Node> arguments;
    if (TreeUtils.isEnumSuper(tree)) {
        // Don't convert arguments for enum super calls.  The AST contains no actual arguments, while
        // the method element expects two arguments, leading to an exception in convertCallArguments.
        // Since no actual arguments are present in the AST that is being checked, it shouldn't cause
        // any harm to omit the conversions.
        // See also BaseTypeVisitor.visitMethodInvocation and QualifierPolymorphism.annotate.
        arguments = Collections.emptyList();
    } else {
        arguments = convertCallArguments(method, actualExprs);
    }
    // TODO: lock the receiver for synchronized methods
    MethodInvocationNode node = new MethodInvocationNode(tree, target, arguments, getCurrentPath());
    List<? extends TypeMirror> thrownTypes = element.getThrownTypes();
    Set<TypeMirror> thrownSet = new LinkedHashSet<>(thrownTypes.size() + uncheckedExceptionTypes.size());
    // Add exceptions explicitly mentioned in the throws clause.
    thrownSet.addAll(thrownTypes);
    // Add types to account for unchecked exceptions
    thrownSet.addAll(uncheckedExceptionTypes);
    ExtendedNode extendedNode = extendWithNodeWithExceptions(node, thrownSet);
    /* Check for the TerminatesExecution annotation. */
    Element methodElement = TreeUtils.elementFromTree(tree);
    boolean terminatesExecution = annotationProvider.getDeclAnnotation(methodElement, TerminatesExecution.class) != null;
    if (terminatesExecution) {
        extendedNode.setTerminatesExecution(true);
    }
    return node;
}