1 /**
2 The contents of this file are subject to the Mozilla Public License Version 1.1
3 (the "License"); you may not use this file except in compliance with the License.
4 You may obtain a copy of the License at http://www.mozilla.org/MPL/
5 Software distributed under the License is distributed on an "AS IS" basis,
6 WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the
7 specific language governing rights and limitations under the License.
8
9 The Original Code is "HL7EncoderWriter.java". Description:
10 ""
11
12 The Initial Developer of the Original Code is University Health Network. Copyright (C)
13 2001. All Rights Reserved.
14
15 Contributor(s): ______________________________________.
16
17 Alternatively, the contents of this file may be used under the terms of the
18 GNU General Public License (the �GPL�), in which case the provisions of the GPL are
19 applicable instead of those above. If you wish to allow use of your version of this
20 file only under the terms of the GPL and not to allow others to use your version
21 of this file under the MPL, indicate your decision by deleting the provisions above
22 and replace them with the notice and other provisions required by the GPL License.
23 If you do not delete the provisions above, a recipient may use your version of
24 this file under either the MPL or the GPL.
25
26 */
27
28 package ca.uhn.hl7v2.llp;
29
30 import java.io.BufferedOutputStream;
31 import java.io.IOException;
32 import java.io.OutputStream;
33 import java.io.OutputStreamWriter;
34 import java.nio.charset.Charset;
35
36 import static ca.uhn.hl7v2.llp.MllpConstants.CHARSET_KEY;
37
38 /**
39 * Writes HL7 messages to an OutputStream. The character set defaults to US-ASCII.
40 * It can be changed by setting the system property ca.uhn.hl7v2.llp.charset to another value that
41 * is the name of a valid java.nio.charset.Charset. If this property is set to "default", then
42 * the system default is used.
43 *
44 * <p/>
45 *
46 * @author Damian Horton; mods by Bryan Tripp
47 * @author Christian Ohr
48 */
49
50 abstract class HL7EncoderWriter<T extends MllpEncoder> implements HL7Writer {
51
52 private OutputStream out;
53 private final T encoder;
54 private Charset charset;
55 protected boolean omitBOM;
56
57 /**
58 * Creates a HL7EncoderWriter with no output stream specified - <code>setOutputStream</code>
59 * must be called before attempting to write any messages.
60 */
61 public HL7EncoderWriter() {
62 encoder = initEncoder();
63 }
64
65 /**
66 * Creates a HL7EncoderWriter, specifying the underlying output stream.
67 */
68 public HL7EncoderWriter(OutputStream out) throws IOException {
69 setOutputStream(out);
70 encoder = initEncoder();
71 }
72
73 /**
74 * Creates a HL7EncoderWriter, specifying the underlying output stream.
75 */
76 public HL7EncoderWriter(OutputStream out, Charset charset, boolean omitBOM) {
77 this.out = out;
78 this.charset = charset;
79 this.omitBOM = omitBOM;
80 encoder = initEncoder();
81 }
82
83 protected abstract T initEncoder();
84
85 /**
86 * Sets the underlying output stream to which messages are written.
87 */
88 public synchronized void setOutputStream(OutputStream out) {
89 if (out == null) throw new NullPointerException("OutputStream must not be null");
90 this.out = new BufferedOutputStream(out);
91 }
92
93 /**
94 * Sends a complete message to the underlying output stream, delimited
95 * according to the minimal lower layer protocol.
96 */
97 public synchronized void writeMessage(String message) throws LLPException, IOException {
98 if (message == null) {
99 throw new NullPointerException("Message must not be null");
100 }
101 encoder.putMessage(message, out);
102 }
103
104 /**
105 * Sends a complete message to the underlying output stream, delimited
106 * according to the minimal lower layer protocol, using the specified character set.
107 */
108 public synchronized void writeMessage(String message, String charset) throws IOException {
109 if (message == null) {
110 throw new NullPointerException("Message may not be null");
111 }
112 OutputStreamWriter writer = new OutputStreamWriter(out, charset);
113 writer.write(MllpConstants.START_BYTE);
114 writer.write(message);
115 writer.write(MllpConstants.END_BYTE1);
116 writer.write(MllpConstants.END_BYTE2);
117 writer.flush();
118 }
119
120 public synchronized void close() throws IOException {
121 if (out != null) out.close();
122 }
123
124 protected Charset getCharset() {
125 if (charset == null) {
126 String charsetString = System.getProperty(CHARSET_KEY, "US-ASCII");
127 if (charsetString.equals("default")) {
128 charset = Charset.defaultCharset();
129 } else {
130 charset = Charset.forName(charsetString);
131 }
132 }
133 return charset;
134 }
135 }