1   /*
2    * Copyright (C) 2009 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    * http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package com.google.common.collect;
18  
19  import com.google.common.annotations.GwtCompatible;
20  
21  import java.lang.reflect.Array;
22  
23  // TODO(kevinb): guava javadoc path seems set wrong, doesn't find that last
24  // import
25  /**
26   * Version of {@link GwtPlatform} used in hosted-mode.  It includes methods in
27   * {@link Platform} that requires different implementions in web mode and
28   * hosted mode.  It is factored out from {@link Platform} because {@code
29   * GwtScriptOnly} (which is applied to the emul version) supports only public
30   * classes and methods.
31   *
32   * @author Hayward Chan
33   */
34  // TODO(hhchan): Once we start using server-side source in hosted mode, we won't
35  // need this.
36  @GwtCompatible(emulated = true)
37  public final class GwtPlatform {
38  
39    private GwtPlatform() {}
40  
41    /** See {@link Platform#newArray(Object[], int)} */
42    public static <T> T[] newArray(T[] reference, int length) {
43      Class<?> type = reference.getClass().getComponentType();
44  
45      // the cast is safe because
46      // result.getClass() == reference.getClass().getComponentType()
47      @SuppressWarnings("unchecked")
48      T[] result = (T[]) Array.newInstance(type, length);
49      return result;
50    }
51  }