001 /*
002 * Copyright 2004-2005 Stephen J. McConnell.
003 * Copyright 2004 Niclas Hedhman.
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
014 * implied.
015 *
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020 package net.dpml.transit;
021
022 /**
023 * The ModernLayout decodes artifacts into a layout scheme that follows the
024 * convention of group/name/version/expanded-name pattern. Specifically the
025 * layout maps artifacts according to the rule
026 * [group[/[subgroup[/...]]]/[name]/[version]/name[-[version]].type.
027 * Example: <code>artifact:jar:metro/cache/dpml-cache-main#1.0.0</code>
028 * would return the path <code>metro/cache/dpml-cache-main/1.0.0/dpml-cache-main-1.0.0.jar</code>.
029 *
030 * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
031 * @version 1.0.3
032 */
033 public class ModernLayout
034 implements Layout
035 {
036 /**
037 * Return the base path for an artifact. The base path is derived from
038 * the artifact group and type. The base path value represents
039 * the directory path relative to a repository root of the directory containing
040 * this artifact.
041 *
042 * @param artifact the resource artifact
043 * @return the base path
044 */
045 public final String resolveBase( Artifact artifact )
046 {
047 String version = artifact.getVersion();
048 if( null == version )
049 {
050 if( null == artifact.getGroup() )
051 {
052 return artifact.getName();
053 }
054 else
055 {
056 String group = getGroupPath( artifact );
057 return group + "/" + artifact.getName();
058 }
059 }
060 else
061 {
062 if( null == artifact.getGroup() )
063 {
064 return artifact.getName() + "/" + version;
065 }
066 else
067 {
068 String group = getGroupPath( artifact );
069 return group + "/" + artifact.getName() + "/" + version;
070 }
071 }
072 }
073
074 /**
075 * Returns the full path of the artifact relative to a logical root directory.
076 * The full path is equivalent to the base path and artifact filename using the
077 * pattern "[base]/[filename]". Path values may be used to resolve an artifact
078 * from a remote repository or local cache relative to the repository or cache
079 * root.
080 *
081 * @param artifact the resource artifact
082 * @see #resolveBase
083 * @see #resolveFilename
084 * @return the logical artifact path
085 */
086 public final String resolvePath( Artifact artifact )
087 {
088 return resolveBase( artifact ) + "/" + resolveFilename( artifact );
089 }
090
091 /**
092 * Return the expanded filename of the artifact. The filename is expressed
093 * as [name]-[version].[type] or in case of a null version simply [name].[type].
094 *
095 * @param artifact the resource artifact
096 * @return the artifact expanded filename
097 */
098 public String resolveFilename( Artifact artifact )
099 {
100 String scheme = artifact.getScheme();
101 String filename = resolveBaseFilename( artifact );
102 if( "artifact".equals( scheme ) )
103 {
104 return filename;
105 }
106 else if( "link".equals( scheme ) )
107 {
108 return filename + ".link";
109 }
110 else
111 {
112 final String error =
113 "Protocol not recognized: " + scheme;
114 throw new TransitRuntimeException( error );
115 }
116 }
117
118 private String resolveBaseFilename( Artifact artifact )
119 {
120 String version = artifact.getVersion();
121 if( null == version )
122 {
123 return artifact.getName() + "." + artifact.getType();
124 }
125 else
126 {
127 return artifact.getName() + "-" + version + "." + artifact.getType();
128 }
129 }
130
131 /**
132 * To be compatible with the maven-2 strategy we need to subsitute period
133 * characters with a group separator.
134 * @param artifact the artifact from which to resolve the group path
135 * @return the group path
136 */
137 private String getGroupPath( Artifact artifact )
138 {
139 String group = artifact.getGroup();
140 return group.replace( '.', '/' );
141 }
142 }