1 /*
2 * Copyright (C) 2010, Google Inc.
3 * Copyright (C) 2008, Marek Zawirski <marek.zawirski@gmail.com>
4 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
5 *
6 * This program and the accompanying materials are made available under the
7 * terms of the Eclipse Distribution License v. 1.0 which is available at
8 * https://www.eclipse.org/org/documents/edl-v10.php.
9 *
10 * SPDX-License-Identifier: BSD-3-Clause
11 */
12
13 package org.eclipse.jgit.transport;
14
15 import java.util.Collection;
16 import java.util.Map;
17
18 import org.eclipse.jgit.lib.Ref;
19
20 /**
21 * Represent connection for operation on a remote repository.
22 * <p>
23 * Currently all operations on remote repository (fetch and push) provide
24 * information about remote refs. Every connection is able to be closed and
25 * should be closed - this is a connection client responsibility.
26 *
27 * @see Transport
28 */
29 public interface Connection extends AutoCloseable {
30 /**
31 * Get the complete map of refs advertised as available for fetching or
32 * pushing.
33 *
34 * @return available/advertised refs: map of refname to ref. Never null. Not
35 * modifiable. The collection can be empty if the remote side has no
36 * refs (it is an empty/newly created repository).
37 */
38 Map<String, Ref> getRefsMap();
39
40 /**
41 * Get the complete list of refs advertised as available for fetching or
42 * pushing.
43 * <p>
44 * The returned refs may appear in any order. If the caller needs these to
45 * be sorted, they should be copied into a new array or List and then sorted
46 * by the caller as necessary.
47 *
48 * @return available/advertised refs. Never null. Not modifiable. The
49 * collection can be empty if the remote side has no refs (it is an
50 * empty/newly created repository).
51 */
52 Collection<Ref> getRefs();
53
54 /**
55 * Get a single advertised ref by name.
56 * <p>
57 * The name supplied should be valid ref name. To get a peeled value for a
58 * ref (aka <code>refs/tags/v1.0^{}</code>) use the base name (without
59 * the <code>^{}</code> suffix) and look at the peeled object id.
60 *
61 * @param name
62 * name of the ref to obtain.
63 * @return the requested ref; null if the remote did not advertise this ref.
64 */
65 Ref getRef(String name);
66
67 /**
68 * {@inheritDoc}
69 * <p>
70 * Close any resources used by this connection.
71 * <p>
72 * If the remote repository is contacted by a network socket this method
73 * must close that network socket, disconnecting the two peers. If the
74 * remote repository is actually local (same system) this method must close
75 * any open file handles used to read the "remote" repository.
76 * <p>
77 * If additional messages were produced by the remote peer, these should
78 * still be retained in the connection instance for {@link #getMessages()}.
79 * <p>
80 * {@code AutoClosable.close()} declares that it throws {@link Exception}.
81 * Implementers shouldn't throw checked exceptions. This override narrows
82 * the signature to prevent them from doing so.
83 */
84 @Override
85 void close();
86
87 /**
88 * Get the additional messages, if any, returned by the remote process.
89 * <p>
90 * These messages are most likely informational or error messages, sent by
91 * the remote peer, to help the end-user correct any problems that may have
92 * prevented the operation from completing successfully. Application UIs
93 * should try to show these in an appropriate context.
94 * <p>
95 * The message buffer is available after {@link #close()} has been called.
96 * Prior to closing the connection, the message buffer may be empty.
97 *
98 * @return the messages returned by the remote, most likely terminated by a
99 * newline (LF) character. The empty string is returned if the
100 * remote produced no additional messages.
101 */
102 String getMessages();
103
104 /**
105 * User agent advertised by the remote server.
106 *
107 * @return agent (version of Git) running on the remote server. Null if the
108 * server does not advertise this version.
109 * @since 4.0
110 */
111 String getPeerUserAgent();
112 }