1 package org.apache.maven.api.services;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import org.apache.maven.api.annotations.Experimental;
23 import org.apache.maven.api.annotations.Nonnull;
24
25 import java.util.ArrayList;
26 import java.util.Collection;
27 import java.util.Collections;
28
29 import org.apache.maven.api.Session;
30
31 /**
32 * Base class for requests.
33 *
34 * @since 4.0
35 */
36 @Experimental
37 abstract class BaseRequest
38 {
39
40 private final Session session;
41
42 protected BaseRequest( @Nonnull Session session )
43 {
44 this.session = nonNull( session, "session cannot be null" );
45 }
46
47 @Nonnull
48 public Session getSession()
49 {
50 return session;
51 }
52
53 public static <T> T nonNull( T obj, String message )
54 {
55 if ( obj == null )
56 {
57 throw new IllegalArgumentException( message );
58 }
59 return obj;
60 }
61
62 protected static <T> Collection<T> unmodifiable( Collection<T> obj )
63 {
64 return obj != null && !obj.isEmpty()
65 ? Collections.unmodifiableCollection( new ArrayList<>( obj ) ) : Collections.emptyList();
66 }
67 }