org.atombeat.xquery.functions.util.CopyFile.java Source code

Introduction

Here is the source code for org.atombeat.xquery.functions.util.CopyFile.java

Source

/*
 *  eXist Open Source Native XML Database
 *  Copyright (C) 2001-09 Wolfgang M. Meier
 *  wolfgang@exist-db.org
 *  http://exist.sourceforge.net
 *  
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *  
 *  $Id: GetData.java 9749 2009-08-09 23:18:12Z ixitar $
 */
package org.atombeat.xquery.functions.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.math.BigInteger;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
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.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;

/**
 */
public class CopyFile extends BasicFunction {

    protected static final Log logger = LogFactory.getLog(CopyFile.class);

    public final static FunctionSignature signature = new FunctionSignature(
            new QName("copy-file", AtomBeatUtilModule.NAMESPACE_URI, AtomBeatUtilModule.PREFIX),
            "Copy a file to another location.",
            new SequenceType[] {
                    new FunctionParameterSequenceType("from", Type.STRING, Cardinality.EXACTLY_ONE,
                            "The path to the file to copy."),
                    new FunctionParameterSequenceType("to", Type.STRING, Cardinality.EXACTLY_ONE,
                            "The path where the new file will be stored.") },
            new FunctionReturnSequenceType(Type.STRING, Cardinality.ZERO_OR_ONE,
                    "an MD5 digest of the content, or empty if there was a problem"));

    public CopyFile(XQueryContext context) {
        super(context, signature);
    }

    /* (non-Javadoc)
     * @see org.exist.xquery.BasicFunction#eval(org.exist.xquery.value.Sequence[], org.exist.xquery.value.Sequence)
     */
    public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {

        // try to copy 
        try {
            String from = args[0].getStringValue();
            String to = args[1].getStringValue();
            File fromFile = new File(from);
            File toFile = new File(to);

            InputStream in = new FileInputStream(fromFile);
            MessageDigest md5 = MessageDigest.getInstance("MD5");
            in = new DigestInputStream(in, md5);
            OutputStream out = new FileOutputStream(toFile);

            Stream.copy(in, out);

            String signature = new BigInteger(1, md5.digest()).toString(16);
            return new StringValue(signature);

        } catch (IOException ioe) {
            throw new XPathException(this, "An IO exception ocurred: " + ioe.getMessage(), ioe);
        } catch (NoSuchAlgorithmException e) {
            throw new XPathException(this, "A message digest exception ocurred: " + e.getMessage(), e);
        }

    }

}