package org.eclipse.aether;

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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *  http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
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A listener being notified of events from the repository system. In general, the system sends events upon termination of an operation like artifactResolved(RepositoryEvent) regardless whether it succeeded or failed so listeners need to inspect the event details carefully. Also, the listener may be called from an arbitrary thread. Note: Implementors are strongly advised to inherit from AbstractRepositoryListener instead of directly implementing this interface. 
See Also:
RepositorySystemSession.getRepositoryListener()
TransferListener
@noimplement
This interface is not intended to be implemented by clients.
@noextend
This interface is not intended to be extended by clients./**
 * A listener being notified of events from the repository system. In general, the system sends events upon termination
 * of an operation like {@link #artifactResolved(RepositoryEvent)} regardless whether it succeeded or failed so
 * listeners need to inspect the event details carefully. Also, the listener may be called from an arbitrary thread.
 * <em>Note:</em> Implementors are strongly advised to inherit from {@link AbstractRepositoryListener} instead of
 * directly implementing this interface.
 * 
 * @see org.eclipse.aether.RepositorySystemSession#getRepositoryListener()
 * @see org.eclipse.aether.transfer.TransferListener
 * @noimplement This interface is not intended to be implemented by clients.
 * @noextend This interface is not intended to be extended by clients.
 */
public interface RepositoryListener
{

    
Notifies the listener of a syntactically or semantically invalid artifact descriptor. RepositoryEvent.getArtifact() indicates the artifact whose descriptor is invalid and RepositoryEvent.getExceptions() carries the encountered errors. Depending on the session's ArtifactDescriptorPolicy, the underlying repository operation might abort with an exception or ignore the invalid descriptor. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of a syntactically or semantically invalid artifact descriptor.
     * {@link RepositoryEvent#getArtifact()} indicates the artifact whose descriptor is invalid and
     * {@link RepositoryEvent#getExceptions()} carries the encountered errors. Depending on the session's
     * {@link org.eclipse.aether.resolution.ArtifactDescriptorPolicy}, the underlying repository operation might abort
     * with an exception or ignore the invalid descriptor.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDescriptorInvalid( RepositoryEvent event );

    
Notifies the listener of a missing artifact descriptor. RepositoryEvent.getArtifact() indicates the artifact whose descriptor is missing. Depending on the session's ArtifactDescriptorPolicy, the underlying repository operation might abort with an exception or ignore the missing descriptor. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of a missing artifact descriptor. {@link RepositoryEvent#getArtifact()} indicates the
     * artifact whose descriptor is missing. Depending on the session's
     * {@link org.eclipse.aether.resolution.ArtifactDescriptorPolicy}, the underlying repository operation might abort
     * with an exception or ignore the missing descriptor.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDescriptorMissing( RepositoryEvent event );

    
Notifies the listener of syntactically or semantically invalid metadata. RepositoryEvent.getMetadata() indicates the invalid metadata and RepositoryEvent.getExceptions() carries the encountered errors. The underlying repository operation might still succeed, depending on whether the metadata in question is actually needed to carry out the resolution process. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of syntactically or semantically invalid metadata. {@link RepositoryEvent#getMetadata()}
     * indicates the invalid metadata and {@link RepositoryEvent#getExceptions()} carries the encountered errors. The
     * underlying repository operation might still succeed, depending on whether the metadata in question is actually
     * needed to carry out the resolution process.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataInvalid( RepositoryEvent event );

    
Notifies the listener of an artifact that is about to be resolved. RepositoryEvent.getArtifact() denotes the artifact in question. Unlike the artifactDownloading(RepositoryEvent) event, this event is fired regardless whether the artifact already exists locally or not. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact that is about to be resolved. {@link RepositoryEvent#getArtifact()} denotes
     * the artifact in question. Unlike the {@link #artifactDownloading(RepositoryEvent)} event, this event is fired
     * regardless whether the artifact already exists locally or not.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactResolving( RepositoryEvent event );

    
Notifies the listener of an artifact whose resolution has been completed, either successfully or not. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getExceptions() indicates whether the resolution succeeded or failed. Unlike the artifactDownloaded(RepositoryEvent) event, this event is fired regardless whether the artifact already exists locally or not. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact whose resolution has been completed, either successfully or not.
     * {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the resolution succeeded or failed. Unlike the
     * {@link #artifactDownloaded(RepositoryEvent)} event, this event is fired regardless whether the artifact already
     * exists locally or not.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactResolved( RepositoryEvent event );

    
Notifies the listener of some metadata that is about to be resolved. RepositoryEvent.getMetadata() denotes the metadata in question. Unlike the metadataDownloading(RepositoryEvent) event, this event is fired regardless whether the metadata already exists locally or not. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata that is about to be resolved. {@link RepositoryEvent#getMetadata()}
     * denotes the metadata in question. Unlike the {@link #metadataDownloading(RepositoryEvent)} event, this event is
     * fired regardless whether the metadata already exists locally or not.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataResolving( RepositoryEvent event );

    
Notifies the listener of some metadata whose resolution has been completed, either successfully or not. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getExceptions() indicates whether the resolution succeeded or failed. Unlike the metadataDownloaded(RepositoryEvent) event, this event is fired regardless whether the metadata already exists locally or not. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata whose resolution has been completed, either successfully or not.
     * {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the resolution succeeded or failed. Unlike the
     * {@link #metadataDownloaded(RepositoryEvent)} event, this event is fired regardless whether the metadata already
     * exists locally or not.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataResolved( RepositoryEvent event );

    
Notifies the listener of an artifact that is about to be downloaded from a remote repository. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getRepository() the source repository. Unlike the artifactResolving(RepositoryEvent) event, this event is only fired when the artifact does not already exist locally. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact that is about to be downloaded from a remote repository.
     * {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getRepository()} the source repository. Unlike the
     * {@link #artifactResolving(RepositoryEvent)} event, this event is only fired when the artifact does not already
     * exist locally.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDownloading( RepositoryEvent event );

    
Notifies the listener of an artifact whose download has been completed, either successfully or not. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getExceptions() indicates whether the download succeeded or failed. Unlike the artifactResolved(RepositoryEvent) event, this event is only fired when the artifact does not already exist locally. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact whose download has been completed, either successfully or not.
     * {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the download succeeded or failed. Unlike the
     * {@link #artifactResolved(RepositoryEvent)} event, this event is only fired when the artifact does not already
     * exist locally.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDownloaded( RepositoryEvent event );

    
Notifies the listener of some metadata that is about to be downloaded from a remote repository. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getRepository() the source repository. Unlike the metadataResolving(RepositoryEvent) event, this event is only fired when the metadata does not already exist locally. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata that is about to be downloaded from a remote repository.
     * {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getRepository()} the source repository. Unlike the
     * {@link #metadataResolving(RepositoryEvent)} event, this event is only fired when the metadata does not already
     * exist locally.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataDownloading( RepositoryEvent event );

    
Notifies the listener of some metadata whose download has been completed, either successfully or not. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getExceptions() indicates whether the download succeeded or failed. Unlike the metadataResolved(RepositoryEvent) event, this event is only fired when the metadata does not already exist locally. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata whose download has been completed, either successfully or not.
     * {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the download succeeded or failed. Unlike the
     * {@link #metadataResolved(RepositoryEvent)} event, this event is only fired when the metadata does not already
     * exist locally.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataDownloaded( RepositoryEvent event );

    
Notifies the listener of an artifact that is about to be installed to the local repository. RepositoryEvent.getArtifact() denotes the artifact in question. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact that is about to be installed to the local repository.
     * {@link RepositoryEvent#getArtifact()} denotes the artifact in question.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactInstalling( RepositoryEvent event );

    
Notifies the listener of an artifact whose installation to the local repository has been completed, either successfully or not. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getExceptions() indicates whether the installation succeeded or failed. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact whose installation to the local repository has been completed, either
     * successfully or not. {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the installation succeeded or failed.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactInstalled( RepositoryEvent event );

    
Notifies the listener of some metadata that is about to be installed to the local repository. RepositoryEvent.getMetadata() denotes the metadata in question. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata that is about to be installed to the local repository.
     * {@link RepositoryEvent#getMetadata()} denotes the metadata in question.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataInstalling( RepositoryEvent event );

    
Notifies the listener of some metadata whose installation to the local repository has been completed, either successfully or not. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getExceptions() indicates whether the installation succeeded or failed. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata whose installation to the local repository has been completed, either
     * successfully or not. {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the installation succeeded or failed.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataInstalled( RepositoryEvent event );

    
Notifies the listener of an artifact that is about to be uploaded to a remote repository. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getRepository() the destination repository. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact that is about to be uploaded to a remote repository.
     * {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getRepository()} the destination repository.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDeploying( RepositoryEvent event );

    
Notifies the listener of an artifact whose upload to a remote repository has been completed, either successfully or not. RepositoryEvent.getArtifact() denotes the artifact in question and RepositoryEvent.getExceptions() indicates whether the upload succeeded or failed. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of an artifact whose upload to a remote repository has been completed, either successfully
     * or not. {@link RepositoryEvent#getArtifact()} denotes the artifact in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the upload succeeded or failed.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void artifactDeployed( RepositoryEvent event );

    
Notifies the listener of some metadata that is about to be uploaded to a remote repository. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getRepository() the destination repository. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata that is about to be uploaded to a remote repository.
     * {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getRepository()} the destination repository.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataDeploying( RepositoryEvent event );

    
Notifies the listener of some metadata whose upload to a remote repository has been completed, either successfully or not. RepositoryEvent.getMetadata() denotes the metadata in question and RepositoryEvent.getExceptions() indicates whether the upload succeeded or failed. 
Params:
event – The event details, must not be null./**
     * Notifies the listener of some metadata whose upload to a remote repository has been completed, either
     * successfully or not. {@link RepositoryEvent#getMetadata()} denotes the metadata in question and
     * {@link RepositoryEvent#getExceptions()} indicates whether the upload succeeded or failed.
     * 
     * @param event The event details, must not be {@code null}.
     */
    void metadataDeployed( RepositoryEvent event );

}