/*

 * Copyright (c) 2004, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package javax.xml.bind.annotation.adapters;

/**

 *

 * <p>

 * Replaces any tab, CR, and LF by a whitespace character ' ',

 * as specified in <a href="http://www.w3.org/TR/xmlschema-2/#rf-whiteSpace">the whitespace facet 'replace'</a>

 *

 * @author Kohsuke Kawaguchi, Martin Grebac

 * @since 1.6, JAXB 2.0

 */

public final class NormalizedStringAdapter extends XmlAdapter<String,String> {

    /**

     * Replace any tab, CR, and LF by a whitespace character ' ',

     * as specified in <a href="http://www.w3.org/TR/xmlschema-2/#rf-whiteSpace">the whitespace facet 'replace'</a>

     */

    public String unmarshal(String text) {

        if(text==null)      return null;    // be defensive

        int i=text.length()-1;

        // look for the first whitespace char.

        while( i>=0 && !isWhiteSpaceExceptSpace(text.charAt(i)) )

            i--;

        if( i<0 )

            // no such whitespace. replace(text)==text.

            return text;

        // we now know that we need to modify the text.

        // allocate a char array to do it.

        char[] buf = text.toCharArray();

        buf[i--] = ' ';

        for( ; i>=0; i-- )

            if( isWhiteSpaceExceptSpace(buf[i]))

                buf[i] = ' ';

        return new String(buf);

    }

    /**

     * No-op.

     *

     * Just return the same string given as the parameter.

     */

        public String marshal(String s) {

            return s;

        }

    /**

     * Returns true if the specified char is a white space character

     * but not 0x20.

     */

    protected static boolean isWhiteSpaceExceptSpace(char ch) {

        // most of the characters are non-control characters.

        // so check that first to quickly return false for most of the cases.

        if( ch>=0x20 )   return false;

        // other than we have to do four comparisons.

        return ch == 0x9 || ch == 0xA || ch == 0xD;

    }

}