/*
* eXist Open Source Native XML Database
* Copyright (C) 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.util;
import org.apache.log4j.Logger;
import org.exist.dom.QName;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.IntegerValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
/**
* Converts the supplied number in given base to other base.
*
* @author ljo
*/
public class BaseConverter extends BasicFunction {
protected static final Logger logger = Logger.getLogger(BaseConverter.class);
private static final FunctionParameterSequenceType number_param = new FunctionParameterSequenceType("number", Type.ITEM, Cardinality.EXACTLY_ONE, "The number to convert");
private static final FunctionParameterSequenceType int_param = new FunctionParameterSequenceType("number", Type.INTEGER, Cardinality.EXACTLY_ONE, "The number to convert");
private static final FunctionParameterSequenceType base_param = new FunctionParameterSequenceType("base", Type.INTEGER, Cardinality.EXACTLY_ONE, "The base of $number");
private static final FunctionReturnSequenceType int_result = new FunctionReturnSequenceType(Type.INTEGER, Cardinality.EXACTLY_ONE, "the xs:integer representation of $number in base $base");
private static final FunctionReturnSequenceType string_result = new FunctionReturnSequenceType(Type.STRING, Cardinality.EXACTLY_ONE, "the xs:string representation of $number in base $base");
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("base-to-integer", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Converts the number $number from base $base to xs:integer.",
new SequenceType[]{ number_param, base_param },
int_result),
new FunctionSignature(
new QName("integer-to-base", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Converts the xs:integer $number (unsigned) into base $base as xs:string. Bases 2, 8, and 16 are supported.",
new SequenceType[]{ int_param, base_param },
string_result)
};
public enum Base {
BINARY(2), OCTAL(8), DECIMAL(10), HEXADECIMAL(16);
public final int base;
Base(int base) {
this.base = base;
}
static public Base getBase(int otherBase) {
for (Base b : Base.values()) {
if (otherBase == b.base) {
return b;
}
}
return DECIMAL;
}
}
public BaseConverter(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
/* (non-Javadoc)
* @see org.exist.xquery.Expression#eval(org.exist.dom.DocumentSet, org.exist.xquery.value.Sequence, org.exist.xquery.value.Item)
*/
public Sequence eval(Sequence[] args, Sequence contextSequence)
throws XPathException {
int intValue;
String stringValue;
String number = args[0].itemAt(0).getStringValue();
int intBase = ((IntegerValue) args[1].itemAt(0)).getInt();
if (isCalledAs("base-to-integer")) {
intValue = Integer.parseInt(number, intBase);
return new IntegerValue(intValue);
} else {
switch (Base.getBase(intBase)) {
case BINARY:
stringValue = Integer.toBinaryString(Integer.parseInt(number));
break;
case OCTAL:
stringValue = Integer.toOctalString(Integer.parseInt(number));
break;
//case DECIMAL:
//stringValue = number;
//break;
case HEXADECIMAL:
stringValue = Integer.toHexString(Integer.parseInt(number));
break;
default:
{
logger.error("Unhandled base for conversion target in integer-to-base().");
throw new XPathException("Unhandled base for conversion target in integer-to-base().");
}
}
return new StringValue(stringValue);
}
}
}