1 /*
2 * Copyright (C) 2009-2010, Google Inc. and others
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Distribution License v. 1.0 which is available at
6 * https://www.eclipse.org/org/documents/edl-v10.php.
7 *
8 * SPDX-License-Identifier: BSD-3-Clause
9 */
10
11 package org.eclipse.jgit.util.io;
12
13 import static java.nio.charset.StandardCharsets.UTF_8;
14
15 import java.io.ByteArrayOutputStream;
16 import java.io.IOException;
17 import java.io.OutputStream;
18 import java.io.OutputStreamWriter;
19 import java.io.Writer;
20
21 import org.eclipse.jgit.util.RawParseUtils;
22
23 /**
24 * Combines messages from an OutputStream (hopefully in UTF-8) and a Writer.
25 * <p>
26 * This class is primarily meant for {@code BaseConnection} in contexts where a
27 * standard error stream from a command execution, as well as messages from a
28 * side-band channel, need to be combined together into a buffer to represent
29 * the complete set of messages from a remote repository.
30 * <p>
31 * Writes made to the writer are re-encoded as UTF-8 and interleaved into the
32 * buffer that {@link #getRawStream()} also writes to.
33 * <p>
34 * {@link #toString()} returns all written data, after converting it to a String
35 * under the assumption of UTF-8 encoding.
36 * <p>
37 * Internally {@link org.eclipse.jgit.util.RawParseUtils#decode(byte[])} is used
38 * by {@code toString()} tries to work out a reasonably correct character set
39 * for the raw data.
40 */
41 public class MessageWriter extends Writer {
42 private final ByteArrayOutputStream buf;
43
44 private final OutputStreamWriter enc;
45
46 /**
47 * Create an empty writer.
48 */
49 public MessageWriter() {
50 buf = new ByteArrayOutputStream();
51 enc = new OutputStreamWriter(getRawStream(), UTF_8);
52 }
53
54 /** {@inheritDoc} */
55 @Override
56 public void write(char[] cbuf, int off, int len) throws IOException {
57 synchronized (buf) {
58 enc.write(cbuf, off, len);
59 enc.flush();
60 }
61 }
62
63 /**
64 * Get the underlying byte stream that character writes to this writer drop
65 * into.
66 *
67 * @return the underlying byte stream that character writes to this writer
68 * drop into. Writes to this stream should should be in UTF-8.
69 */
70 public OutputStream getRawStream() {
71 return buf;
72 }
73
74 /** {@inheritDoc} */
75 @Override
76 public void close() throws IOException {
77 // Do nothing, we are buffered with no resources.
78 }
79
80 /** {@inheritDoc} */
81 @Override
82 public void flush() throws IOException {
83 // Do nothing, we are buffered with no resources.
84 }
85
86 /** @return string version of all buffered data. */
87 /** {@inheritDoc} */
88 @Override
89 public String toString() {
90 return RawParseUtils.decode(buf.toByteArray());
91 }
92 }