package net.sf.saxon.functions;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.om.Item;
import net.sf.saxon.sort.*;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.value.BooleanValue;
import net.sf.saxon.value.StringValue;
import java.text.RuleBasedCollator;
/**
* Implements the fn:contains() function
*/
public class Contains extends CollatingFunction {
/**
* Get the effective boolean value of the expression. This returns false if the value
* is the empty sequence, a zero-length string, a number equal to zero, or the boolean
* false. Otherwise it returns true.
* @param context The context in which the expression is to be evaluated
* @return the effective boolean value
* @throws net.sf.saxon.trans.XPathException
* if any dynamic error occurs evaluating the
* expression
*/
public boolean effectiveBooleanValue(XPathContext context) throws XPathException {
StringValue arg1 = (StringValue)argument[1].evaluateItem(context);
if (arg1==null || arg1.isZeroLength()) {
return true;
}
StringValue arg0 = (StringValue)argument[0].evaluateItem(context);
if (arg0==null || arg0.isZeroLength()) {
return false;
}
String s0 = arg0.getStringValue();
String s1 = arg1.getStringValue();
if (stringCollator instanceof CodepointCollator) {
// fast path for this common case
return s0.indexOf(s1, 0) >= 0;
} else {
StringCollator collator = getCollator(2, context);
if (collator instanceof NamedCollation &&
((NamedCollation)collator).getCollation() instanceof RuleBasedCollator) {
collator = new RuleBasedSubstringMatcher((RuleBasedCollator)((NamedCollation)collator).getCollation());
}
if (collator instanceof SubstringMatcher) {
return ((SubstringMatcher)collator).contains(s0, s1);
} else {
dynamicError("The collation requested for " + getDisplayName() +
" does not support substring matching", "FOCH0004", context);
return false;
}
}
}
/**
* Evaluate the function
*/
public Item evaluateItem(XPathContext context) throws XPathException {
return BooleanValue.get(effectiveBooleanValue(context));
}
}
//
// The contents of this file are subject to the Mozilla Public License Version
// 1.0 (the "License");
// you may not use this file except in compliance with the License. You may
// obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael Kay,
//
// Portions created by (your name) are Copyright (C) (your legal entity). All
// Rights Reserved.
//
// Contributor(s): none.
//