001package org.eclipse.aether.impl;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 * 
012 *  http://www.apache.org/licenses/LICENSE-2.0
013 * 
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import org.eclipse.aether.RepositorySystemSession;
023
024/**
025 * Evaluates update policies.
026 * 
027 * @noimplement This interface is not intended to be implemented by clients.
028 * @noextend This interface is not intended to be extended by clients.
029 * @provisional This type is provisional and can be changed, moved or removed without prior notice.
030 */
031public interface UpdatePolicyAnalyzer
032{
033
034    /**
035     * Returns the policy with the shorter update interval.
036     * 
037     * @param session The repository system session during which the request is made, must not be {@code null}.
038     * @param policy1 A policy to compare, may be {@code null}.
039     * @param policy2 A policy to compare, may be {@code null}.
040     * @return The policy with the shorter update interval.
041     */
042    String getEffectiveUpdatePolicy( RepositorySystemSession session, String policy1, String policy2 );
043
044    /**
045     * Determines whether the specified modification timestamp satisfies the freshness constraint expressed by the given
046     * update policy.
047     * 
048     * @param session The repository system session during which the check is made, must not be {@code null}.
049     * @param lastModified The timestamp to check against the update policy.
050     * @param policy The update policy, may be {@code null}.
051     * @return {@code true} if the specified timestamp is older than acceptable by the update policy, {@code false}
052     *         otherwise.
053     */
054    boolean isUpdatedRequired( RepositorySystemSession session, long lastModified, String policy );
055
056}