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.apache.maven.api;
20
21 import java.util.Optional;
22
23 import org.apache.maven.api.annotations.Experimental;
24 import org.apache.maven.api.annotations.Nonnull;
25
26 /**
27 * Event sent by maven during various phases of the build process.
28 * Such events can be listened to using {@link Listener}s objects
29 * registered in the {@link Session}.
30 *
31 * @since 4.0.0
32 */
33 @Experimental
34 public interface Event {
35
36 /**
37 * Gets the type of the event.
38 *
39 * @return the type of the event, never {@code null}
40 */
41 @Nonnull
42 EventType getType();
43
44 /**
45 * Gets the session from which this event originates.
46 *
47 * @return the current session, never {@code null}
48 */
49 @Nonnull
50 Session getSession();
51
52 /**
53 * Gets the current project (if any).
54 *
55 * @return the current project or {@code empty()} if not applicable
56 */
57 @Nonnull
58 Optional<Project> getProject();
59
60 /**
61 * Gets the current mojo execution (if any).
62 *
63 * @return the current mojo execution or {@code empty()} if not applicable
64 */
65 @Nonnull
66 Optional<MojoExecution> getMojoExecution();
67
68 /**
69 * Gets the exception that caused the event (if any).
70 *
71 * @return the exception or {@code empty()} if none
72 */
73 Optional<Exception> getException();
74 }