1 package org.eclipse.aether.resolution;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.Collections;
23 import java.util.List;
24
25 import org.eclipse.aether.RepositoryException;
26 import org.eclipse.aether.transfer.ArtifactNotFoundException;
27 import org.eclipse.aether.transfer.RepositoryOfflineException;
28
29 /**
30 * Thrown in case of a unresolvable artifacts.
31 */
32 public class ArtifactResolutionException
33 extends RepositoryException
34 {
35
36 private final transient List<ArtifactResult> results;
37
38 /**
39 * Creates a new exception with the specified results.
40 *
41 * @param results The resolution results at the point the exception occurred, may be {@code null}.
42 */
43 public ArtifactResolutionException( List<ArtifactResult> results )
44 {
45 super( getMessage( results ), getCause( results ) );
46 this.results = ( results != null ) ? results : Collections.<ArtifactResult>emptyList();
47 }
48
49 /**
50 * Creates a new exception with the specified results and detail message.
51 *
52 * @param results The resolution results at the point the exception occurred, may be {@code null}.
53 * @param message The detail message, may be {@code null}.
54 */
55 public ArtifactResolutionException( List<ArtifactResult> results, String message )
56 {
57 super( message, getCause( results ) );
58 this.results = ( results != null ) ? results : Collections.<ArtifactResult>emptyList();
59 }
60
61 /**
62 * Creates a new exception with the specified results, detail message and cause.
63 *
64 * @param results The resolution results at the point the exception occurred, may be {@code null}.
65 * @param message The detail message, may be {@code null}.
66 * @param cause The exception that caused this one, may be {@code null}.
67 */
68 public ArtifactResolutionException( List<ArtifactResult> results, String message, Throwable cause )
69 {
70 super( message, cause );
71 this.results = ( results != null ) ? results : Collections.<ArtifactResult>emptyList();
72 }
73
74 /**
75 * Gets the resolution results at the point the exception occurred. Despite being incomplete, callers might want to
76 * use these results to fail gracefully and continue their operation with whatever interim data has been gathered.
77 *
78 * @return The resolution results or {@code null} if unknown.
79 */
80 public List<ArtifactResult> getResults()
81 {
82 return results;
83 }
84
85 /**
86 * Gets the first result from {@link #getResults()}. This is a convenience method for cases where callers know only
87 * a single result/request is involved.
88 *
89 * @return The (first) resolution result or {@code null} if none.
90 */
91 public ArtifactResult getResult()
92 {
93 return ( results != null && !results.isEmpty() ) ? results.get( 0 ) : null;
94 }
95
96 private static String getMessage( List<? extends ArtifactResult> results )
97 {
98 StringBuilder buffer = new StringBuilder( 256 );
99
100 buffer.append( "The following artifacts could not be resolved: " );
101
102 int unresolved = 0;
103
104 String sep = "";
105 for ( ArtifactResult result : results )
106 {
107 if ( !result.isResolved() )
108 {
109 unresolved++;
110
111 buffer.append( sep );
112 buffer.append( result.getRequest().getArtifact() );
113 sep = ", ";
114 }
115 }
116
117 Throwable cause = getCause( results );
118 if ( cause != null )
119 {
120 if ( unresolved == 1 )
121 {
122 buffer.setLength( 0 );
123 buffer.append( cause.getMessage() );
124 }
125 else
126 {
127 buffer.append( ": " ).append( cause.getMessage() );
128 }
129 }
130
131 return buffer.toString();
132 }
133
134 private static Throwable getCause( List<? extends ArtifactResult> results )
135 {
136 for ( ArtifactResult result : results )
137 {
138 if ( !result.isResolved() )
139 {
140 Throwable notFound = null, offline = null;
141 for ( Throwable t : result.getExceptions() )
142 {
143 if ( t instanceof ArtifactNotFoundException )
144 {
145 if ( notFound == null )
146 {
147 notFound = t;
148 }
149 if ( offline == null && t.getCause() instanceof RepositoryOfflineException )
150 {
151 offline = t;
152 }
153 }
154 else
155 {
156 return t;
157 }
158
159 }
160 if ( offline != null )
161 {
162 return offline;
163 }
164 if ( notFound != null )
165 {
166 return notFound;
167 }
168 }
169 }
170 return null;
171 }
172
173 }