package client.net.sf.saxon.ce.style;
import client.net.sf.saxon.ce.expr.*;
import client.net.sf.saxon.ce.functions.SystemFunction;
import client.net.sf.saxon.ce.expr.instruct.Executable;
import client.net.sf.saxon.ce.expr.instruct.SimpleNodeConstructor;
import client.net.sf.saxon.ce.om.AttributeCollection;
import client.net.sf.saxon.ce.om.Axis;
import client.net.sf.saxon.ce.om.NodeInfo;
import client.net.sf.saxon.ce.om.StandardNames;
import client.net.sf.saxon.ce.tree.iter.AxisIterator;
import client.net.sf.saxon.ce.trans.XPathException;
import client.net.sf.saxon.ce.type.BuiltInAtomicType;
import client.net.sf.saxon.ce.type.Type;
import client.net.sf.saxon.ce.value.StringValue;
import client.net.sf.saxon.ce.value.Whitespace;
/**
* Common superclass for XSLT elements whose content template produces a text
* value: xsl:text, xsl:value-of, xsl:attribute, xsl:comment, and xsl:processing-instruction
*/
public abstract class XSLLeafNodeConstructor extends StyleElement {
//protected String stringValue = null;
protected Expression select = null;
/**
* Method for use by subclasses (processing-instruction and namespace) that take
* a name and a select attribute
* @return the expression defining the name attribute
* @throws XPathException
*/
protected Expression prepareAttributesNameAndSelect() throws XPathException {
Expression name = null;
String nameAtt = null;
String selectAtt = null;
AttributeCollection atts = getAttributeList();
for (int a=0; a<atts.getLength(); a++) {
int nc = atts.getNameCode(a);
String f = getNamePool().getClarkName(nc);
if (f.equals(StandardNames.NAME)) {
nameAtt = Whitespace.trim(atts.getValue(a));
} else if (f.equals(StandardNames.SELECT)) {
selectAtt = Whitespace.trim(atts.getValue(a));
} else {
checkUnknownAttribute(nc);
}
}
if (nameAtt==null) {
reportAbsence("name");
} else {
name = makeAttributeValueTemplate(nameAtt);
}
if (selectAtt!=null) {
select = makeExpression(selectAtt);
}
return name;
}
/**
* Determine whether this node is an instruction.
*
* @return true - it is an instruction
*/
public boolean isInstruction() {
return true;
}
/**
* Determine whether this type of element is allowed to contain a template-body
*
* @return true: yes, it may contain a template-body
*/
public boolean mayContainSequenceConstructor() {
return true;
}
public void validate(Declaration decl) throws XPathException {
if (select != null && hasChildNodes()) {
String errorCode = getErrorCodeForSelectPlusContent();
compileError("An " + getDisplayName() + " element with a select attribute must be empty", errorCode);
}
AxisIterator kids = iterateAxis(Axis.CHILD);
NodeInfo first = (NodeInfo)kids.next();
if (select == null) {
if (first == null) {
// there are no child nodes and no select attribute
//stringValue = "";
select = new StringLiteral(StringValue.EMPTY_STRING);
} else {
if (kids.next() == null) {
// there is exactly one child node
if (first.getNodeKind() == Type.TEXT) {
// it is a text node: optimize for this case
select = new StringLiteral(first.getStringValue());
}
}
}
}
}
/**
* Get the error code to be returned when the element has a select attribute but is not empty.
* @return the error code defined for this condition, for this particular instruction
*/
protected abstract String getErrorCodeForSelectPlusContent();
protected void compileContent(Executable exec, Declaration decl, SimpleNodeConstructor inst, Expression separator) throws XPathException {
if (separator == null) {
separator = new StringLiteral(StringValue.SINGLE_SPACE);
}
try {
if (select == null) {
select = compileSequenceConstructor(exec, decl, iterateAxis(Axis.CHILD));
}
select = makeSimpleContentConstructor(select, separator);
inst.setSelect(select, exec.getConfiguration());
} catch (XPathException err) {
compileError(err);
}
}
/**
* Construct an expression that implements the rules of "constructing simple content":
* given an expression to select the base sequence, and an expression to compute the separator,
* build an (unoptimized) expression to produce the value of the node as a string.
* @param select the expression that selects the base sequence
* @param separator the expression that computes the separator
* @return an expression that returns a string containing the string value of the constructed node
*/
public static Expression makeSimpleContentConstructor(Expression select, Expression separator) {
// Merge adjacent text nodes
select = new AdjacentTextNodeMerger(select);
// Atomize the result
select = new Atomizer(select);
// Convert each atomic value to a string
select = new AtomicSequenceConverter(select, BuiltInAtomicType.STRING);
// Join the resulting strings with a separator
select = SystemFunction.makeSystemFunction("string-join", new Expression[]{select, separator});
// All that's left for the instruction to do is to construct the right kind of node
return select;
}
}
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is “Incompatible With Secondary Licenses”, as defined by the Mozilla Public License, v. 2.0.