1 /*
2 * Copyright (C) 2016, Matthias Sohn <matthias.sohn@sap.com> 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 package org.eclipse.jgit.attributes;
11
12 import java.io.IOException;
13 import java.io.InputStream;
14 import java.io.OutputStream;
15 import java.util.Map;
16 import java.util.Set;
17 import java.util.concurrent.ConcurrentHashMap;
18
19 import org.eclipse.jgit.lib.Repository;
20
21 /**
22 * Registry for built-in filters
23 *
24 * @since 4.6
25 */
26 public class FilterCommandRegistry {
27 private static Map<String, FilterCommandFactory> filterCommandRegistry = new ConcurrentHashMap<>();
28
29 /**
30 * Register a {@link org.eclipse.jgit.attributes.FilterCommandFactory}
31 * responsible for creating
32 * {@link org.eclipse.jgit.attributes.FilterCommand}s for a certain command
33 * name. If the factory f1 is registered for the name "jgit://builtin/x"
34 * then a call to <code>getCommand("jgit://builtin/x", ...)</code> will call
35 * <code>f1(...)</code> to create a new instance of
36 * {@link org.eclipse.jgit.attributes.FilterCommand}
37 *
38 * @param filterCommandName
39 * the command name for which this factory is registered
40 * @param factory
41 * the factory responsible for creating
42 * {@link org.eclipse.jgit.attributes.FilterCommand}s for the
43 * specified name
44 * @return the previous factory associated with <tt>commandName</tt>, or
45 * <tt>null</tt> if there was no mapping for <tt>commandName</tt>
46 */
47 public static FilterCommandFactory register(String filterCommandName,
48 FilterCommandFactory factory) {
49 return filterCommandRegistry.put(filterCommandName, factory);
50 }
51
52 /**
53 * Unregister the {@link org.eclipse.jgit.attributes.FilterCommandFactory}
54 * registered for the given command name
55 *
56 * @param filterCommandName
57 * the FilterCommandFactory's filter command name
58 * @return the previous factory associated with <tt>filterCommandName</tt>,
59 * or <tt>null</tt> if there was no mapping for <tt>commandName</tt>
60 */
61 public static FilterCommandFactory unregister(String filterCommandName) {
62 return filterCommandRegistry.remove(filterCommandName);
63 }
64
65 /**
66 * Check whether any
67 * {@link org.eclipse.jgit.attributes.FilterCommandFactory} is registered
68 * for a given command name
69 *
70 * @param filterCommandName
71 * the name for which the registry should be checked
72 * @return <code>true</code> if any factory was registered for the name
73 */
74 public static boolean isRegistered(String filterCommandName) {
75 return filterCommandRegistry.containsKey(filterCommandName);
76 }
77
78 /**
79 * Get registered filter commands
80 *
81 * @return Set of commandNames for which a
82 * {@link org.eclipse.jgit.attributes.FilterCommandFactory} is
83 * registered
84 */
85 public static Set<String> getRegisteredFilterCommands() {
86 return filterCommandRegistry.keySet();
87 }
88
89 /**
90 * Create a new {@link org.eclipse.jgit.attributes.FilterCommand} for the
91 * given name. A factory must be registered for the name in advance.
92 *
93 * @param filterCommandName
94 * The name for which a new
95 * {@link org.eclipse.jgit.attributes.FilterCommand} should be
96 * created
97 * @param db
98 * the repository this command should work on
99 * @param in
100 * the {@link java.io.InputStream} this
101 * {@link org.eclipse.jgit.attributes.FilterCommand} should read
102 * from
103 * @param out
104 * the {@link java.io.OutputStream} this
105 * {@link org.eclipse.jgit.attributes.FilterCommand} should write
106 * to
107 * @return the command if a command could be created or <code>null</code> if
108 * there was no factory registered for that name
109 * @throws java.io.IOException
110 */
111 public static FilterCommand createFilterCommand(String filterCommandName,
112 Repository db, InputStream in, OutputStream out)
113 throws IOException {
114 FilterCommandFactory cf = filterCommandRegistry.get(filterCommandName);
115 return (cf == null) ? null : cf.create(db, in, out);
116 }
117
118 }