/*
* eXist Open Source Native XML Database
* Copyright (C) 2005-2009 The eXist Project
* http://exist-db.org
*
* 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 2
* 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.
*
* $Id$
*/
package org.exist.xquery.functions.fn;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.util.XMLChar;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
import org.exist.xquery.ErrorCodes;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.NumericValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceIterator;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
/**
*
* @author wolf
*
*/
public class FunCodepointsToString extends BasicFunction {
protected static final Logger logger = Logger.getLogger(FunCodepointsToString.class);
public final static FunctionSignature signature =
new FunctionSignature(
new QName("codepoints-to-string", Function.BUILTIN_FUNCTION_NS, FnModule.PREFIX),
"Creates an xs:string from a sequence of code points. Returns the " +
"zero-length string if $codepoints is the empty sequence. " +
"If any of the code points in $codepoints is not a " +
"legal XML character, an error is raised",
new SequenceType[] {
new FunctionParameterSequenceType("codepoints", Type.INTEGER,
Cardinality.ZERO_OR_MORE, "The codepoints as a sequence of xs:integer values"),
},
new FunctionReturnSequenceType(Type.STRING, Cardinality.EXACTLY_ONE,
"The string constructed from the codepoints if valid"));
public FunCodepointsToString(XQueryContext context) {
super(context, signature);
}
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES,
"DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES,
"CONTEXT SEQUENCE", contextSequence);}
}
Sequence result;
if (args[0].isEmpty()) {
result = StringValue.EMPTY_STRING;
} else {
final StringBuilder buf = new StringBuilder();
for (final SequenceIterator i = args[0].iterate(); i.hasNext(); ) {
final long next = ((NumericValue)i.nextItem()).getLong();
if (next < 0 || next > Integer.MAX_VALUE ||
!XMLChar.isValid((int)next)) {
throw new XPathException(this,
ErrorCodes.FOCH0001,
"Codepoint " + next + " is not a valid character.");
}
if (next < 65536) {
buf.append((char)next);
} else { // output a surrogate pair
buf.append(XMLChar.highSurrogate((int)next));
buf.append(XMLChar.lowSurrogate((int)next));
}
}
result = new StringValue(buf.toString());
}
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
}