001/* ***** BEGIN LICENSE BLOCK *****
002 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
003 *
004 * The contents of this file are subject to the Mozilla Public License Version
005 * 1.1 (the "License"); you may not use this file except in compliance with
006 * the License. You may obtain a copy of the License at
007 * http://www.mozilla.org/MPL/
008 *
009 * Software distributed under the License is distributed on an "AS IS" basis,
010 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
011 * for the specific language governing rights and limitations under the
012 * License.
013 *
014 * The Original Code is part of dcm4che, an implementation of DICOM(TM) in
015 * Java(TM), hosted at https://github.com/gunterze/dcm4che.
016 *
017 * The Initial Developer of the Original Code is
018 * Agfa Healthcare.
019 * Portions created by the Initial Developer are Copyright (C) 2012
020 * the Initial Developer. All Rights Reserved.
021 *
022 * Contributor(s):
023 * See @authors listed below
024 *
025 * Alternatively, the contents of this file may be used under the terms of
026 * either the GNU General Public License Version 2 or later (the "GPL"), or
027 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
028 * in which case the provisions of the GPL or the LGPL are applicable instead
029 * of those above. If you wish to allow use of your version of this file only
030 * under the terms of either the GPL or the LGPL, and not to allow others to
031 * use your version of this file under the terms of the MPL, indicate your
032 * decision by deleting the provisions above and replace them with the notice
033 * and other provisions required by the GPL or the LGPL. If you do not delete
034 * the provisions above, a recipient may use your version of this file under
035 * the terms of any one of the MPL, the GPL or the LGPL.
036 *
037 * ***** END LICENSE BLOCK ***** */
038
039package org.dcm4che3.hl7;
040
041import java.io.IOException;
042import java.io.Writer;
043
044import org.xml.sax.Attributes;
045import org.xml.sax.SAXException;
046import org.xml.sax.helpers.DefaultHandler;
047
048/**
049 * @author Gunter Zeilinger <gunterze@gmail.com>
050 *
051 */
052public class HL7ContentHandler extends DefaultHandler {
053
054    private final Writer writer;
055    private char[] delimiters = Delimiter.DEFAULT.toCharArray();
056    private final char[] escape = { '\\', 0, '\\' };
057    private boolean ignoreCharacters = true;
058
059    public HL7ContentHandler(Writer writer) {
060        this.writer = writer;
061    }
062
063    @Override
064    public void startElement(String uri, String localName, String qName,
065            Attributes atts) throws SAXException {
066        try {
067            switch (qName.charAt(0)) {
068            case 'f':
069                if (qName.equals("field")) {
070                    writer.write(delimiters[0]);
071                    ignoreCharacters = false;
072                    return;
073                }
074                break;
075            case 'c':
076                if (qName.equals("component")) {
077                    writer.write(delimiters[1]);
078                    ignoreCharacters = false;
079                    return;
080                }
081                break;
082            case 'r':
083                if (qName.equals("repeat")) {
084                    writer.write(delimiters[2]);
085                    ignoreCharacters = false;
086                    return;
087                }
088                break;
089            case 'e':
090                if (qName.equals("escape")) {
091                    writer.write(delimiters[3]);
092                    ignoreCharacters = false;
093                    return;
094                }
095                break;
096            case 's':
097                if (qName.equals("subcomponent")) {
098                    writer.write(delimiters[4]);
099                    ignoreCharacters = false;
100                    return;
101                }
102                break;
103            case 'M':
104                if (qName.equals("MSH")) {
105                    startHeaderSegment(qName, atts);
106                    return;
107                }
108                break;
109            case 'B':
110                if (qName.equals("BHS")) {
111                    startHeaderSegment(qName, atts);
112                    return;
113                }
114                break;
115            case 'F':
116                if (qName.equals("FHS")) {
117                    startHeaderSegment(qName, atts);
118                    return;
119                }
120                break;
121            case 'h':
122                if (qName.equals("hl7"))
123                    return;
124            }
125            writer.write(qName);
126        } catch (Exception e) {
127            throw new SAXException(e);
128        }
129    }
130
131    private void startHeaderSegment(String seg, Attributes atts) throws IOException {
132        Delimiter[] values = Delimiter.values();
133        for (int i = 0; i < values.length; i++) {
134            String value = atts.getValue(values[i].attribute());
135            if (value != null)
136                delimiters[i] = value.charAt(0);
137        }
138        this.escape[0] = this.escape[2] = delimiters[3];
139        writer.write(seg);
140        writer.write(delimiters);
141    }
142
143    @Override
144    public void endElement(String uri, String localName, String qName)
145            throws SAXException {
146        ignoreCharacters = true;
147        try {
148            switch (qName.charAt(0)) {
149            case 'f':
150                if (qName.equals("field")) return;
151                break;
152            case 'c':
153                if (qName.equals("component")) return;
154                break;
155            case 'r':
156                if (qName.equals("repeat")) return;
157                break;
158            case 'e':
159                if (qName.equals("escape")) {
160                    writer.write(delimiters[3]);
161                    ignoreCharacters = false;
162                    return;
163                }
164                break;
165            case 's':
166                if (qName.equals("subcomponent")) return;
167                break;
168            case 'h':
169                if (qName.equals("hl7")) {
170                    writer.flush();
171                    return;
172                }
173            }
174            writer.write('\r');
175        } catch (Exception e) {
176            throw new SAXException(e);
177        }
178    }
179
180    @Override
181    public void characters(char[] cbuf, int start, int length)
182            throws SAXException {
183        if (ignoreCharacters)
184            return;
185
186        try {
187            int off = start;
188            int end = start + length;
189            char c;
190            char[] delims = delimiters;
191            for (int i = start; i < end; i++) {
192                c = cbuf[i];
193                for (int j = 0; j < delims.length; j++) {
194                    if (c == delims[j]) {
195                        writer.write(cbuf, off, i - off);
196                        off = i + 1;
197                        escape(j);
198                        break;
199                    }
200                }
201            }
202            writer.write(cbuf, off, end - off);
203        } catch (Exception e) {
204            throw new SAXException(e);
205        }
206    }
207
208    private void escape(int delimIndex) throws IOException {
209        escape[1] = Delimiter.ESCAPE.charAt(delimIndex);
210        writer.write(escape);
211    }
212}