org.argeo.slc.repo/src/org/eclipse/aether/collection/VersionFilter.java

   1 /*******************************************************************************
   2  * Copyright (c) 2013, 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.collection;
  12
  13 import java.util.Iterator;
  14 import java.util.List;
  15
  16 import org.eclipse.aether.RepositoryException;
  17 import org.eclipse.aether.RepositorySystemSession;
  18 import org.eclipse.aether.graph.Dependency;
  19 import org.eclipse.aether.repository.ArtifactRepository;
  20 import org.eclipse.aether.repository.RemoteRepository;
  21 import org.eclipse.aether.version.Version;
  22 import org.eclipse.aether.version.VersionConstraint;
  23
  24 /**
  25  * Decides which versions matching a version range should actually be considered for the dependency graph. The version
  26  * filter is not invoked for dependencies that do not declare a version range but a single version.
  27  * <p>
  28  * <strong>Note:</strong> Implementations must be stateless.
  29  * <p>
  30  * <em>Warning:</em> This hook is called from a hot spot and therefore implementations should pay attention to
  31  * performance. Among others, implementations should provide a semantic {@link Object#equals(Object) equals()} method.
  32  *
  33  * @see org.eclipse.aether.RepositorySystemSession#getVersionFilter()
  34  * @see org.eclipse.aether.RepositorySystem#collectDependencies(org.eclipse.aether.RepositorySystemSession,
  35  *      CollectRequest)
  36  */
  37 public interface VersionFilter
  38 {
  39
  40     /**
  41      * A context used during version filtering to hold relevant data.
  42      *
  43      * @noimplement This interface is not intended to be implemented by clients.
  44      * @noextend This interface is not intended to be extended by clients.
  45      */
  46     interface VersionFilterContext
  47         extends Iterable<Version>
  48     {
  49
  50         /**
  51          * Gets the repository system session during which the version filtering happens.
  52          *
  53          * @return The repository system session, never {@code null}.
  54          */
  55         RepositorySystemSession getSession();
  56
  57         /**
  58          * Gets the dependency whose version range is being filtered.
  59          *
  60          * @return The dependency, never {@code null}.
  61          */
  62         Dependency getDependency();
  63
  64         /**
  65          * Gets the total number of available versions. This count reflects any removals made during version filtering.
  66          *
  67          * @return The total number of available versions.
  68          */
  69         int getCount();
  70
  71         /**
  72          * Gets an iterator over the available versions of the dependency. The iterator returns versions in ascending
  73          * order. Use {@link Iterator#remove()} to exclude a version from further consideration in the dependency graph.
  74          *
  75          * @return The iterator of available versions, never {@code null}.
  76          */
  77         Iterator<Version> iterator();
  78
  79         /**
  80          * Gets the version constraint that was parsed from the dependency's version string.
  81          *
  82          * @return The parsed version constraint, never {@code null}.
  83          */
  84         VersionConstraint getVersionConstraint();
  85
  86         /**
  87          * Gets the repository from which the specified version was resolved.
  88          *
  89          * @param version The version whose source repository should be retrieved, must not be {@code null}.
  90          * @return The repository from which the version was resolved or {@code null} if unknown.
  91          */
  92         ArtifactRepository getRepository( Version version );
  93
  94         /**
  95          * Gets the remote repositories from which the versions were resolved.
  96          *
  97          * @return The (read-only) list of repositories, never {@code null}.
  98          */
  99         List<RemoteRepository> getRepositories();
 100
 101     }
 102
 103     /**
 104      * Filters the available versions for a given dependency. Implementations will usually call
 105      * {@link VersionFilterContext#iterator() context.iterator()} to inspect the available versions and use
 106      * {@link java.util.Iterator#remove()} to delete unacceptable versions. If no versions remain after all filtering
 107      * has been performed, the dependency collection process will automatically fail, i.e. implementations need not
 108      * handle this situation on their own.
 109      *
 110      * @param context The version filter context, must not be {@code null}.
 111      * @throws RepositoryException If the filtering could not be performed.
 112      */
 113     void filterVersions( VersionFilterContext context )
 114         throws RepositoryException;
 115
 116     /**
 117      * Derives a version filter for the specified collection context. The derived filter will be used to handle version
 118      * ranges encountered in child dependencies of the current node. When calculating the child filter, implementors are
 119      * strongly advised to simply return the current instance if nothing changed to help save memory.
 120      *
 121      * @param context The dependency collection context, must not be {@code null}.
 122      * @return The version filter for the target node or {@code null} if versions should not be filtered any more.
 123      */
 124     VersionFilter deriveChildFilter( DependencyCollectionContext context );
 125
 126 }