1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79

/**
 * Copyright 2011 ArcBees Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.gwtplatform.common.client;

import com.google.inject.Provider;

/**
 * This class can be used to contain a group of providers that should all sit
 * behind the same split point. That is, if the code for one provided object is
 * loaded, so is the code for the others. This is useful when the provided
 * objects share the bulk of their code, which would end up in the left-overs if
 * the objects were behind their individual split points.
 * <p />
 * Here is an example use of {@link ProviderBundle}:
 *
 * <pre>
 * public class MyPresenterBundle extends ProviderBundle {
 *   public final static int ID_Object1 = 0;
 *   public final static int ID_Object2 = 1;
 *   public final static int BUNDLE_SIZE = 2;
 *
 *   &#064;Inject
 *   MyPresenterBundle(
 *       final Provider<Object1> object1Provider,
 *       final Provider<Object2> object2Provider) {
 *     super( BUNDLE_SIZE );
 *     providers[ID_Object1] = object1Provider;
 *     providers[ID_Object2] = object2Provider;
 *   }
 * }</pre>
 *
 * @author Philippe Beaudoin
 */
public class ProviderBundle {

  protected final Provider<?> providers[];

  /**
   * Constructs a {@link ProviderBundle} containing a given number of providers.
   * After calling this constructor you should set the provider manually like
   * so:
   *
   * <pre>
   *     providers[0] = object1Provider;
   *     providers[1] = object2Provider;
   *     ...
   *     providers[bundleSize-1] = objectNProvider;</pre>
   *
   * @param bundleSize The number of providers in the bundle.
   */
  public ProviderBundle(int bundleSize) {
    providers = new Provider<?>[bundleSize];
  }

  /**
   * Accesses a provider given its id.
   *
   * @param providerId The id of the provider to access.
   * @return The provider.
   */
  public Provider<?> get(int providerId) {
    return providers[providerId];
  }

}