1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.eclipse.aether.util.repository;
20
21 import org.eclipse.aether.repository.Proxy;
22 import org.eclipse.aether.repository.ProxySelector;
23 import org.eclipse.aether.repository.RemoteRepository;
24
25 import static java.util.Objects.requireNonNull;
26
27 /**
28 * A proxy selector that delegates to another selector but only if a repository has no proxy yet. If a proxy has already
29 * been assigned to a repository, that is selected.
30 */
31 public final class ConservativeProxySelector implements ProxySelector {
32
33 private final ProxySelector selector;
34
35 /**
36 * Creates a new selector that delegates to the specified selector.
37 *
38 * @param selector The selector to delegate to in case a repository has no proxy yet, must not be {@code null}.
39 */
40 public ConservativeProxySelector(ProxySelector selector) {
41 this.selector = requireNonNull(selector, "proxy selector cannot be null");
42 }
43
44 public Proxy getProxy(RemoteRepository repository) {
45 requireNonNull(repository, "repository cannot be null");
46 Proxy proxy = repository.getProxy();
47 if (proxy != null) {
48 return proxy;
49 }
50 return selector.getProxy(repository);
51 }
52 }