org.argeo.slc.repo/src/org/eclipse/aether/resolution/ArtifactResolutionException.java

   1 /*******************************************************************************
   2  * Copyright (c) 2010, 2014 Sonatype, Inc.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/epl-v10.html
   7  *
   8  * Contributors:
   9  *    Sonatype, Inc. - initial API and implementation
  10  *******************************************************************************/
  11 package org.eclipse.aether.resolution;
  12
  13 import java.util.Collections;
  14 import java.util.List;
  15
  16 import org.eclipse.aether.RepositoryException;
  17 import org.eclipse.aether.transfer.ArtifactNotFoundException;
  18 import org.eclipse.aether.transfer.RepositoryOfflineException;
  19
  20 /**
  21  * Thrown in case of a unresolvable artifacts.
  22  */
  23 public class ArtifactResolutionException
  24     extends RepositoryException
  25 {
  26
  27     private final transient List<ArtifactResult> results;
  28
  29     /**
  30      * Creates a new exception with the specified results.
  31      *
  32      * @param results The resolution results at the point the exception occurred, may be {@code null}.
  33      */
  34     public ArtifactResolutionException( List<ArtifactResult> results )
  35     {
  36         super( getMessage( results ), getCause( results ) );
  37         this.results = ( results != null ) ? results : Collections.<ArtifactResult> emptyList();
  38     }
  39
  40     /**
  41      * Creates a new exception with the specified results and detail message.
  42      *
  43      * @param results The resolution results at the point the exception occurred, may be {@code null}.
  44      * @param message The detail message, may be {@code null}.
  45      */
  46     public ArtifactResolutionException( List<ArtifactResult> results, String message )
  47     {
  48         super( message, getCause( results ) );
  49         this.results = ( results != null ) ? results : Collections.<ArtifactResult> emptyList();
  50     }
  51
  52     /**
  53      * Creates a new exception with the specified results, detail message and cause.
  54      *
  55      * @param results The resolution results at the point the exception occurred, may be {@code null}.
  56      * @param message The detail message, may be {@code null}.
  57      * @param cause The exception that caused this one, may be {@code null}.
  58      */
  59     public ArtifactResolutionException( List<ArtifactResult> results, String message, Throwable cause )
  60     {
  61         super( message, cause );
  62         this.results = ( results != null ) ? results : Collections.<ArtifactResult> emptyList();
  63     }
  64
  65     /**
  66      * Gets the resolution results at the point the exception occurred. Despite being incomplete, callers might want to
  67      * use these results to fail gracefully and continue their operation with whatever interim data has been gathered.
  68      *
  69      * @return The resolution results or {@code null} if unknown.
  70      */
  71     public List<ArtifactResult> getResults()
  72     {
  73         return results;
  74     }
  75
  76     /**
  77      * Gets the first result from {@link #getResults()}. This is a convenience method for cases where callers know only
  78      * a single result/request is involved.
  79      *
  80      * @return The (first) resolution result or {@code null} if none.
  81      */
  82     public ArtifactResult getResult()
  83     {
  84         return ( results != null && !results.isEmpty() ) ? results.get( 0 ) : null;
  85     }
  86
  87     private static String getMessage( List<? extends ArtifactResult> results )
  88     {
  89         StringBuilder buffer = new StringBuilder( 256 );
  90
  91         buffer.append( "The following artifacts could not be resolved: " );
  92
  93         int unresolved = 0;
  94
  95         String sep = "";
  96         for ( ArtifactResult result : results )
  97         {
  98             if ( !result.isResolved() )
  99             {
 100                 unresolved++;
 101
 102                 buffer.append( sep );
 103                 buffer.append( result.getRequest().getArtifact() );
 104                 sep = ", ";
 105             }
 106         }
 107
 108         Throwable cause = getCause( results );
 109         if ( cause != null )
 110         {
 111             if ( unresolved == 1 )
 112             {
 113                 buffer.setLength( 0 );
 114                 buffer.append( cause.getMessage() );
 115             }
 116             else
 117             {
 118                 buffer.append( ": " ).append( cause.getMessage() );
 119             }
 120         }
 121
 122         return buffer.toString();
 123     }
 124
 125     private static Throwable getCause( List<? extends ArtifactResult> results )
 126     {
 127         for ( ArtifactResult result : results )
 128         {
 129             if ( !result.isResolved() )
 130             {
 131                 Throwable notFound = null, offline = null;
 132                 for ( Throwable t : result.getExceptions() )
 133                 {
 134                     if ( t instanceof ArtifactNotFoundException )
 135                     {
 136                         if ( notFound == null )
 137                         {
 138                             notFound = t;
 139                         }
 140                         if ( offline == null && t.getCause() instanceof RepositoryOfflineException )
 141                         {
 142                             offline = t;
 143                         }
 144                     }
 145                     else
 146                     {
 147                         return t;
 148                     }
 149
 150                 }
 151                 if ( offline != null )
 152                 {
 153                     return offline;
 154                 }
 155                 if ( notFound != null )
 156                 {
 157                     return notFound;
 158                 }
 159             }
 160         }
 161         return null;
 162     }
 163
 164 }