View Javadoc
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.surefire.extensions;
20  
21  import javax.annotation.Nonnull;
22  
23  import java.io.Closeable;
24  import java.io.IOException;
25  import java.nio.channels.ReadableByteChannel;
26  import java.nio.channels.WritableByteChannel;
27  
28  import org.apache.maven.surefire.api.event.Event;
29  import org.apache.maven.surefire.api.fork.ForkNodeArguments;
30  import org.apache.maven.surefire.extensions.util.CountdownCloseable;
31  
32  /**
33   * It's a session object used only by a particular Thread in ForkStarter
34   * and communicates with a dedicated forked JVM. It represents a server.
35   * <br>
36   * <br>
37   * It connects to a remote client by {@link #tryConnectToClient()}, provides a connection string
38   * {@link #getForkNodeConnectionString()} needed by the client in forked JVM, binds event handler and command reader.
39   * This object is called in one Thread.
40   *
41   * @author <a href="mailto:tibordigana@apache.org">Tibor Digana (tibor17)</a>
42   * @since 3.0.0-M5
43   */
44  public abstract class ForkChannel implements Closeable {
45      @Nonnull
46      private final ForkNodeArguments arguments;
47  
48      /**
49       * @param arguments data necessary for command reader and event handler.
50       */
51      protected ForkChannel(@Nonnull ForkNodeArguments arguments) {
52          this.arguments = arguments;
53      }
54  
55      /**
56       * Asynchronously connects to the client.
57       *
58       * @throws IOException if stream fails
59       * @throws InterruptedException if interrupted thread
60       */
61      public abstract void tryConnectToClient() throws IOException, InterruptedException;
62  
63      /**
64       * This is server related class, which if binds to a TCP port, determines the connection string for the client.
65       *
66       * @return a connection string utilized by the client in the fork JVM
67       */
68      public abstract String getForkNodeConnectionString();
69  
70      /**
71       * the permits in {@link CountdownCloseable}.
72       */
73      public abstract int getCountdownCloseablePermits();
74  
75      /**
76       * Binds command handler to the channel. Starts a Thread streaming out the commands.
77       *
78       * @param commands command reader, see {@link CommandReader#readNextCommand()}
79       * @param stdIn    optional standard input stream of the JVM to write the encoded commands into it
80       * @throws IOException if an error in the fork channel
81       * @throws InterruptedException channel interrupted
82       */
83      public abstract void bindCommandReader(@Nonnull CommandReader commands, WritableByteChannel stdIn)
84              throws IOException, InterruptedException;
85  
86      /**
87       * Starts a Thread reading the events.
88       *
89       * @param eventHandler       event eventHandler
90       * @param countdownCloseable count down of the final call of {@link Closeable#close()}
91       * @param stdOut             optional standard output stream of the JVM
92       * @throws IOException if an error in the fork channel
93       * @throws InterruptedException channel interrupted
94       */
95      public abstract void bindEventHandler(
96              @Nonnull EventHandler<Event> eventHandler,
97              @Nonnull CountdownCloseable countdownCloseable,
98              ReadableByteChannel stdOut)
99              throws IOException, InterruptedException;
100 
101     @Nonnull
102     protected ForkNodeArguments getArguments() {
103         return arguments;
104     }
105 
106     public abstract void disable();
107 
108     @Override
109     public abstract void close() throws IOException;
110 }