com.sun.org.apache.xalan.internal.xsltc.compiler.util.IntType Java Examples

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * Compile the function call and treat as an expression
 * Update true/false-lists.
 */
@Override
public void translateDesynthesized(ClassGenerator classGen,
                                   MethodGenerator methodGen)
{
    Type type = Type.Boolean;
    if (_chosenMethodType != null)
        type = _chosenMethodType.resultType();

    final InstructionList il = methodGen.getInstructionList();
    translate(classGen, methodGen);

    if ((type instanceof BooleanType) || (type instanceof IntType)) {
        _falseList.add(il.append(new IFEQ(null)));
    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * Parse the attributes of the xsl:sort element
 */
public void parseContents(Parser parser) {

    final SyntaxTreeNode parent = getParent();
    if (!(parent instanceof ApplyTemplates) &&
        !(parent instanceof ForEach)) {
        reportError(this, parser, ErrorMsg.STRAY_SORT_ERR, null);
        return;
    }

    // Parse the select expression (node string value if no expression)
    _select = parser.parseExpression(this, "select", "string(.)");

    // Get the sort order; default is 'ascending'
    String val = getAttribute("order");
    if (val.length() == 0) val = "ascending";
    _order = AttributeValue.create(this, val, parser);

    // Get the sort data type; default is text
    val = getAttribute("data-type");
    if (val.length() == 0) {
        try {
            final Type type = _select.typeCheck(parser.getSymbolTable());
            if (type instanceof IntType)
                val = "number";
            else
                val = "text";
        }
        catch (TypeCheckError e) {
            val = "text";
        }
    }
    _dataType = AttributeValue.create(this, val, parser);

    val =  getAttribute("lang");
    _lang = AttributeValue.create(this, val, parser);
    // Get the case order; default is language dependant
    val = getAttribute("case-order");
    _caseOrder = AttributeValue.create(this, val, parser);
}
 

/**
 * Parse the attributes of the xsl:sort element
 */
public void parseContents(Parser parser) {

    final SyntaxTreeNode parent = getParent();
    if (!(parent instanceof ApplyTemplates) &&
        !(parent instanceof ForEach)) {
        reportError(this, parser, ErrorMsg.STRAY_SORT_ERR, null);
        return;
    }

    // Parse the select expression (node string value if no expression)
    _select = parser.parseExpression(this, "select", "string(.)");

    // Get the sort order; default is 'ascending'
    String val = getAttribute("order");
    if (val.length() == 0) val = "ascending";
    _order = AttributeValue.create(this, val, parser);

    // Get the sort data type; default is text
    val = getAttribute("data-type");
    if (val.length() == 0) {
        try {
            final Type type = _select.typeCheck(parser.getSymbolTable());
            if (type instanceof IntType)
                val = "number";
            else
                val = "text";
        }
        catch (TypeCheckError e) {
            val = "text";
        }
    }
    _dataType = AttributeValue.create(this, val, parser);

    val =  getAttribute("lang");
    _lang = AttributeValue.create(this, val, parser);
    // Get the case order; default is language dependant
    val = getAttribute("case-order");
    _caseOrder = AttributeValue.create(this, val, parser);
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * Parse the attributes of the xsl:sort element
 */
public void parseContents(Parser parser) {

    final SyntaxTreeNode parent = getParent();
    if (!(parent instanceof ApplyTemplates) &&
        !(parent instanceof ForEach)) {
        reportError(this, parser, ErrorMsg.STRAY_SORT_ERR, null);
        return;
    }

    // Parse the select expression (node string value if no expression)
    _select = parser.parseExpression(this, "select", "string(.)");

    // Get the sort order; default is 'ascending'
    String val = getAttribute("order");
    if (val.length() == 0) val = "ascending";
    _order = AttributeValue.create(this, val, parser);

    // Get the sort data type; default is text
    val = getAttribute("data-type");
    if (val.length() == 0) {
        try {
            final Type type = _select.typeCheck(parser.getSymbolTable());
            if (type instanceof IntType)
                val = "number";
            else
                val = "text";
        }
        catch (TypeCheckError e) {
            val = "text";
        }
    }
    _dataType = AttributeValue.create(this, val, parser);

    val =  getAttribute("lang");
    _lang = AttributeValue.create(this, val, parser);
    // Get the case order; default is language dependant
    val = getAttribute("case-order");
    _caseOrder = AttributeValue.create(this, val, parser);
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * This method is part of a little trick that is needed to use local
 * variables inside nested for-each loops. See the initializeVariables()
 * method in the ForEach class for an explanation
 */
public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // This is only done for local variables that are actually used
    if (isLocal() && !_refs.isEmpty()) {
        // Create a variable slot if none is allocated
        if (_local == null) {
            _local = methodGen.addLocalVariable2(getEscapedName(),
                                                 _type.toJCType(),
                                                 null);
        }
        // Push the default value on the JVM's stack
        if ((_type instanceof IntType) ||
            (_type instanceof NodeType) ||
            (_type instanceof BooleanType))
            il.append(new ICONST(0)); // 0 for node-id, integer and boolean
        else if (_type instanceof RealType)
            il.append(new DCONST(0)); // 0.0 for floating point numbers
        else
            il.append(new ACONST_NULL()); // and 'null' for anything else

        // Mark the store as the start of the live range of the variable
        _local.setStart(il.append(_type.STORE(_local.getIndex())));

    }
}
 

/**
 * Typing rules: see XSLT Reference by M. Kay page 345.
 */
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    final Type tleft = _left.typeCheck(stable);
    final Type tright = _right.typeCheck(stable);

    if (tleft.isSimple() && tright.isSimple()) {
        if (tleft != tright) {
            if (tleft instanceof BooleanType) {
                _right = new CastExpr(_right, Type.Boolean);
            }
            else if (tright instanceof BooleanType) {
                _left = new CastExpr(_left, Type.Boolean);
            }
            else if (tleft instanceof NumberType ||
                     tright instanceof NumberType) {
                _left = new CastExpr(_left, Type.Real);
                _right = new CastExpr(_right, Type.Real);
            }
            else {          // both compared as strings
                _left = new CastExpr(_left,   Type.String);
                _right = new CastExpr(_right, Type.String);
            }
        }
    }
    else if (tleft instanceof ReferenceType) {
        _right = new CastExpr(_right, Type.Reference);
    }
    else if (tright instanceof ReferenceType) {
        _left = new CastExpr(_left, Type.Reference);
    }
    // the following 2 cases optimize @attr|.|.. = 'string'
    else if (tleft instanceof NodeType && tright == Type.String) {
        _left = new CastExpr(_left, Type.String);
    }
    else if (tleft == Type.String && tright instanceof NodeType) {
        _right = new CastExpr(_right, Type.String);
    }
    // optimize node/node
    else if (tleft instanceof NodeType && tright instanceof NodeType) {
        _left = new CastExpr(_left, Type.String);
        _right = new CastExpr(_right, Type.String);
    }
    else if (tleft instanceof NodeType && tright instanceof NodeSetType) {
        // compare(Node, NodeSet) will be invoked
    }
    else if (tleft instanceof NodeSetType && tright instanceof NodeType) {
        swapArguments();    // for compare(Node, NodeSet)
    }
    else {
        // At least one argument is of type node, node-set or result-tree

        // Promote an expression of type node to node-set
        if (tleft instanceof NodeType) {
            _left = new CastExpr(_left, Type.NodeSet);
        }
        if (tright instanceof NodeType) {
            _right = new CastExpr(_right, Type.NodeSet);
        }

        // If one arg is a node-set then make it the left one
        if (tleft.isSimple() ||
            tleft instanceof ResultTreeType &&
            tright instanceof NodeSetType) {
            swapArguments();
        }

        // Promote integers to doubles to have fewer compares
        if (_right.getType() instanceof IntType) {
            _right = new CastExpr(_right, Type.Real);
        }
    }
    return _type = Type.Boolean;
}
 

/**
 * Type check a predicate expression. If the type of the expression is
 * number convert it to boolean by adding a comparison with position().
 * Note that if the expression is a parameter, we cannot distinguish
 * at compile time if its type is number or not. Hence, expressions of
 * reference type are always converted to booleans.
 *
 * This method may be called twice, before and after calling
 * <code>dontOptimize()</code>. If so, the second time it should honor
 * the new value of <code>_canOptimize</code>.
 */
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    Type texp = _exp.typeCheck(stable);

    // We need explicit type information for reference types - no good!
    if (texp instanceof ReferenceType) {
        _exp = new CastExpr(_exp, texp = Type.Real);
    }

    // A result tree fragment should not be cast directly to a number type,
    // but rather to a boolean value, and then to a numer (0 or 1).
    // Ref. section 11.2 of the XSLT 1.0 spec
    if (texp instanceof ResultTreeType) {
        _exp = new CastExpr(_exp, Type.Boolean);
        _exp = new CastExpr(_exp, Type.Real);
        texp = _exp.typeCheck(stable);
    }

    // Numerical types will be converted to a position filter
    if (texp instanceof NumberType) {
        // Cast any numerical types to an integer
        if (texp instanceof IntType == false) {
            _exp = new CastExpr(_exp, Type.Int);
        }

        if (_canOptimize) {
            // Nth position optimization. Expression must not depend on context
            _nthPositionFilter =
                !_exp.hasLastCall() && !_exp.hasPositionCall();

            // _nthDescendant optimization - only if _nthPositionFilter is on
            if (_nthPositionFilter) {
                SyntaxTreeNode parent = getParent();
                _nthDescendant = (parent instanceof Step) &&
                    (parent.getParent() instanceof AbsoluteLocationPath);
                return _type = Type.NodeSet;
            }
        }

       // Reset optimization flags
        _nthPositionFilter = _nthDescendant = false;

       // Otherwise, expand [e] to [position() = e]
       final QName position =
            getParser().getQNameIgnoreDefaultNs("position");
       final PositionCall positionCall =
            new PositionCall(position);
       positionCall.setParser(getParser());
       positionCall.setParent(this);

       _exp = new EqualityExpr(Operators.EQ, positionCall,
                                _exp);
       if (_exp.typeCheck(stable) != Type.Boolean) {
           _exp = new CastExpr(_exp, Type.Boolean);
       }
       return _type = Type.Boolean;
    }
    else {
        // All other types will be handled as boolean values
        if (texp instanceof BooleanType == false) {
            _exp = new CastExpr(_exp, Type.Boolean);
        }
        return _type = Type.Boolean;
    }
}
 

/**
 * Type check a predicate expression. If the type of the expression is
 * number convert it to boolean by adding a comparison with position().
 * Note that if the expression is a parameter, we cannot distinguish
 * at compile time if its type is number or not. Hence, expressions of
 * reference type are always converted to booleans.
 *
 * This method may be called twice, before and after calling
 * <code>dontOptimize()</code>. If so, the second time it should honor
 * the new value of <code>_canOptimize</code>.
 */
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    Type texp = _exp.typeCheck(stable);

    // We need explicit type information for reference types - no good!
    if (texp instanceof ReferenceType) {
        _exp = new CastExpr(_exp, texp = Type.Real);
    }

    // A result tree fragment should not be cast directly to a number type,
    // but rather to a boolean value, and then to a numer (0 or 1).
    // Ref. section 11.2 of the XSLT 1.0 spec
    if (texp instanceof ResultTreeType) {
        _exp = new CastExpr(_exp, Type.Boolean);
        _exp = new CastExpr(_exp, Type.Real);
        texp = _exp.typeCheck(stable);
    }

    // Numerical types will be converted to a position filter
    if (texp instanceof NumberType) {
        // Cast any numerical types to an integer
        if (texp instanceof IntType == false) {
            _exp = new CastExpr(_exp, Type.Int);
        }

        if (_canOptimize) {
            // Nth position optimization. Expression must not depend on context
            _nthPositionFilter =
                !_exp.hasLastCall() && !_exp.hasPositionCall();

            // _nthDescendant optimization - only if _nthPositionFilter is on
            if (_nthPositionFilter) {
                SyntaxTreeNode parent = getParent();
                _nthDescendant = (parent instanceof Step) &&
                    (parent.getParent() instanceof AbsoluteLocationPath);
                return _type = Type.NodeSet;
            }
        }

       // Reset optimization flags
        _nthPositionFilter = _nthDescendant = false;

       // Otherwise, expand [e] to [position() = e]
       final QName position =
            getParser().getQNameIgnoreDefaultNs("position");
       final PositionCall positionCall =
            new PositionCall(position);
       positionCall.setParser(getParser());
       positionCall.setParent(this);

       _exp = new EqualityExpr(Operators.EQ, positionCall,
                                _exp);
       if (_exp.typeCheck(stable) != Type.Boolean) {
           _exp = new CastExpr(_exp, Type.Boolean);
       }
       return _type = Type.Boolean;
    }
    else {
        // All other types will be handled as boolean values
        if (texp instanceof BooleanType == false) {
            _exp = new CastExpr(_exp, Type.Boolean);
        }
        return _type = Type.Boolean;
    }
}
 

/**
 * Typing rules: see XSLT Reference by M. Kay page 345.
 */
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    final Type tleft = _left.typeCheck(stable);
    final Type tright = _right.typeCheck(stable);

    if (tleft.isSimple() && tright.isSimple()) {
        if (tleft != tright) {
            if (tleft instanceof BooleanType) {
                _right = new CastExpr(_right, Type.Boolean);
            }
            else if (tright instanceof BooleanType) {
                _left = new CastExpr(_left, Type.Boolean);
            }
            else if (tleft instanceof NumberType ||
                     tright instanceof NumberType) {
                _left = new CastExpr(_left, Type.Real);
                _right = new CastExpr(_right, Type.Real);
            }
            else {          // both compared as strings
                _left = new CastExpr(_left,   Type.String);
                _right = new CastExpr(_right, Type.String);
            }
        }
    }
    else if (tleft instanceof ReferenceType) {
        _right = new CastExpr(_right, Type.Reference);
    }
    else if (tright instanceof ReferenceType) {
        _left = new CastExpr(_left, Type.Reference);
    }
    // the following 2 cases optimize @attr|.|.. = 'string'
    else if (tleft instanceof NodeType && tright == Type.String) {
        _left = new CastExpr(_left, Type.String);
    }
    else if (tleft == Type.String && tright instanceof NodeType) {
        _right = new CastExpr(_right, Type.String);
    }
    // optimize node/node
    else if (tleft instanceof NodeType && tright instanceof NodeType) {
        _left = new CastExpr(_left, Type.String);
        _right = new CastExpr(_right, Type.String);
    }
    else if (tleft instanceof NodeType && tright instanceof NodeSetType) {
        // compare(Node, NodeSet) will be invoked
    }
    else if (tleft instanceof NodeSetType && tright instanceof NodeType) {
        swapArguments();    // for compare(Node, NodeSet)
    }
    else {
        // At least one argument is of type node, node-set or result-tree

        // Promote an expression of type node to node-set
        if (tleft instanceof NodeType) {
            _left = new CastExpr(_left, Type.NodeSet);
        }
        if (tright instanceof NodeType) {
            _right = new CastExpr(_right, Type.NodeSet);
        }

        // If one arg is a node-set then make it the left one
        if (tleft.isSimple() ||
            tleft instanceof ResultTreeType &&
            tright instanceof NodeSetType) {
            swapArguments();
        }

        // Promote integers to doubles to have fewer compares
        if (_right.getType() instanceof IntType) {
            _right = new CastExpr(_right, Type.Real);
        }
    }
    return _type = Type.Boolean;
}
 

/**
 * Typing rules: see XSLT Reference by M. Kay page 345.
 */
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    final Type tleft = _left.typeCheck(stable);
    final Type tright = _right.typeCheck(stable);

    if (tleft.isSimple() && tright.isSimple()) {
        if (tleft != tright) {
            if (tleft instanceof BooleanType) {
                _right = new CastExpr(_right, Type.Boolean);
            }
            else if (tright instanceof BooleanType) {
                _left = new CastExpr(_left, Type.Boolean);
            }
            else if (tleft instanceof NumberType ||
                     tright instanceof NumberType) {
                _left = new CastExpr(_left, Type.Real);
                _right = new CastExpr(_right, Type.Real);
            }
            else {          // both compared as strings
                _left = new CastExpr(_left,   Type.String);
                _right = new CastExpr(_right, Type.String);
            }
        }
    }
    else if (tleft instanceof ReferenceType) {
        _right = new CastExpr(_right, Type.Reference);
    }
    else if (tright instanceof ReferenceType) {
        _left = new CastExpr(_left, Type.Reference);
    }
    // the following 2 cases optimize @attr|.|.. = 'string'
    else if (tleft instanceof NodeType && tright == Type.String) {
        _left = new CastExpr(_left, Type.String);
    }
    else if (tleft == Type.String && tright instanceof NodeType) {
        _right = new CastExpr(_right, Type.String);
    }
    // optimize node/node
    else if (tleft instanceof NodeType && tright instanceof NodeType) {
        _left = new CastExpr(_left, Type.String);
        _right = new CastExpr(_right, Type.String);
    }
    else if (tleft instanceof NodeType && tright instanceof NodeSetType) {
        // compare(Node, NodeSet) will be invoked
    }
    else if (tleft instanceof NodeSetType && tright instanceof NodeType) {
        swapArguments();    // for compare(Node, NodeSet)
    }
    else {
        // At least one argument is of type node, node-set or result-tree

        // Promote an expression of type node to node-set
        if (tleft instanceof NodeType) {
            _left = new CastExpr(_left, Type.NodeSet);
        }
        if (tright instanceof NodeType) {
            _right = new CastExpr(_right, Type.NodeSet);
        }

        // If one arg is a node-set then make it the left one
        if (tleft.isSimple() ||
            tleft instanceof ResultTreeType &&
            tright instanceof NodeSetType) {
            swapArguments();
        }

        // Promote integers to doubles to have fewer compares
        if (_right.getType() instanceof IntType) {
            _right = new CastExpr(_right, Type.Real);
        }
    }
    return _type = Type.Boolean;
}