1 package org.apache.maven.surefire.junitcore.pc;
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 /**
23 * @author Tibor Digana (tibor17)
24 * @see Balancer
25 * @since 2.16
26 */
27 public class BalancerFactory
28 {
29 private BalancerFactory()
30 {
31 }
32
33 /**
34 * Infinite permits.
35 * @return Balancer wih infinite permits
36 */
37 public static Balancer createInfinitePermitsBalancer()
38 {
39 return balancer( 0, false );
40 }
41
42 /**
43 * Balancer without fairness.
44 * Fairness guarantees the waiting schedulers to wake up in order they acquired a permit.
45 *
46 * @param concurrency number of permits to acquire when maintaining concurrency on tests
47 * @return Balancer with given number of permits
48 */
49 public static Balancer createBalancer( int concurrency )
50 {
51 return balancer( concurrency, false );
52 }
53
54 /**
55 * Balancer with fairness.
56 * Fairness guarantees the waiting schedulers to wake up in order they acquired a permit.
57 *
58 * @param concurrency number of permits to acquire when maintaining concurrency on tests
59 * @return Balancer with given number of permits
60 */
61 public static Balancer createBalancerWithFairness( int concurrency )
62 {
63 return balancer( concurrency, true );
64 }
65
66 private static Balancer balancer( int concurrency, boolean fairness )
67 {
68 boolean shouldBalance = concurrency > 0 && concurrency < Integer.MAX_VALUE;
69 return shouldBalance ? new ThreadResourcesBalancer( concurrency, fairness ) : new NullBalancer();
70 }
71 }