001    /**
002    The contents of this file are subject to the Mozilla Public License Version 1.1 
003    (the "License"); you may not use this file except in compliance with the License. 
004    You may obtain a copy of the License at http://www.mozilla.org/MPL/ 
005    Software distributed under the License is distributed on an "AS IS" basis, 
006    WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the 
007    specific language governing rights and limitations under the License. 
008    
009    The Original Code is "MinLLPWriter.java".  Description: 
010    "Title:        MinLLPWriter
011      Description:  Writes HL7 messages to an OutputStream
012      Copyright:    Copyright (c) 2001
013      Company:      University Health Network
014      @author       Damian Horton
015      @version 1.1" 
016    
017    The Initial Developer of the Original Code is University Health Network. Copyright (C) 
018    2001.  All Rights Reserved. 
019    
020    Contributor(s): ______________________________________. 
021    
022    Alternatively, the contents of this file may be used under the terms of the 
023    GNU General Public License (the  �GPL�), in which case the provisions of the GPL are 
024    applicable instead of those above.  If you wish to allow use of your version of this 
025    file only under the terms of the GPL and not to allow others to use your version 
026    of this file under the MPL, indicate your decision by deleting  the provisions above 
027    and replace  them with the notice and other provisions required by the GPL License.  
028    If you do not delete the provisions above, a recipient may use your version of 
029    this file under either the MPL or the GPL. 
030    
031    */
032    
033    package ca.uhn.hl7v2.llp;
034    
035    import java.io.*;
036    import java.nio.charset.Charset;
037    
038    /**
039     * Title:        MinLLPWriter
040     * Description:  Writes HL7 messages to an OutputStream.  The character set defaults to US-ASCII.  
041     * It can be chaged by setting the system property ca.uhn.hl7v2.llp.charset to another value that 
042     * is the name of a valid java.nio.charset.Charset.  If this property is set to "default", then 
043     * the system default is used. 
044     * 
045     * Copyright:    Copyright (c) 2001
046     * Company:      University Health Network
047     * @author       Damian Horton; mods by Bryan Tripp
048     * @version 1.1
049     */
050    
051    public class MinLLPWriter implements HL7Writer
052    {
053            /**
054             * @see MinLLPReader#CHARSET_KEY
055             */
056        public static final String CHARSET_KEY = MinLLPReader.CHARSET_KEY;
057        
058        BufferedWriter myWriter; //reads from the input stream given in the
059                                 //constructor
060        boolean messageStarted = false; //whether or not the necessary characters to
061                                //initialize the message have already been buffered
062    
063        private OutputStream myOutputStream;
064    
065            private Charset charset;
066    
067        /**
068         * Creates a MinLLPWriter with no output stream specified - <code>setOutputStream</code>
069         * must be called before attempting to write any messages. 
070         */
071        public MinLLPWriter() {
072        }
073        
074        /** 
075         * Creates a MinLLPWriter, specifying the underlying output stream.
076         */
077        public MinLLPWriter(OutputStream out) throws IOException {
078            setOutputStream(out);
079        }
080        
081        /** 
082         * Creates a MinLLPWriter, specifying the underlying output stream.
083         */
084        public MinLLPWriter(OutputStream out, Charset theCharset) throws IOException {
085            charset = theCharset;
086            setOutputStream(out);
087        }
088    
089        /** 
090         * Sets the underlying output stream to which messages are written. 
091         */
092        public synchronized void setOutputStream(OutputStream out) throws IOException  
093        {
094            myOutputStream = out;
095            myWriter = new BufferedWriter(getWriter(out));
096        }
097    
098        /** 
099         * Sends a complete message to the underlying output stream, delimited 
100         * according to the minimal lower layer protocol.  
101         */
102        public synchronized void writeMessage(String message) throws LLPException, IOException 
103        {
104            myWriter.write('\u000b');
105            myWriter.write(message);
106            myWriter.write('\u001c' + "\r");
107            myWriter.flush();            
108        }
109    
110        /** 
111         * Sends a complete message to the underlying output stream, delimited 
112         * according to the minimal lower layer protocol, using the specified character set. 
113         */
114        public synchronized void writeMessage(String message, String charset) throws LLPException, IOException 
115        {
116            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(myOutputStream, charset));
117            writer.write('\u000b');
118            writer.write(message);
119            writer.write('\u001c' + "\r");
120            writer.flush();
121        }
122    
123        public synchronized void close() throws java.io.IOException
124        {
125            myWriter.close();
126        }
127        
128        private OutputStreamWriter getWriter(OutputStream theStream) throws IOException {
129            
130            if (charset != null) {
131                return new OutputStreamWriter(theStream, charset);
132            } else {
133                    String charsetString = System.getProperty(CHARSET_KEY, "US-ASCII");
134                    if (charsetString.equals("default")) {
135                        return new OutputStreamWriter(theStream);
136                    } else {
137                        return new OutputStreamWriter(theStream, charsetString);
138                    }
139            }
140        }
141        
142    }