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1   /*
2    * Licensed to The Apereo Foundation under one or more contributor license
3    * agreements. See the NOTICE file distributed with this work for additional
4    * information regarding copyright ownership.
5    *
6    *
7    * The Apereo Foundation licenses this file to you under the Educational
8    * Community License, Version 2.0 (the "License"); you may not use this file
9    * except in compliance with the License. You may obtain a copy of the License
10   * at:
11   *
12   *   http://opensource.org/licenses/ecl2.txt
13   *
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
16   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
17   * License for the specific language governing permissions and limitations under
18   * the License.
19   *
20   */
21  
22  
23  package org.opencastproject.util.data;
24  
25  import static org.opencastproject.util.data.functions.Functions.chuck;
26  
27  /**
28   * Run a side effect.
29   *
30   * @see X
31   */
32  public abstract class Effect0 extends Function0<Void> {
33    @Override
34    public final Void apply() {
35      run();
36      return null;
37    }
38  
39    /** Run the side effect. */
40    protected abstract void run();
41  
42    /** Version of {@link Effect0} that allows for throwing a checked exception. */
43    public abstract static class X extends Effect0 {
44      @Override
45      protected final void run() {
46        try {
47          xrun();
48        } catch (Exception e) {
49          chuck(e);
50        }
51      }
52  
53      /**
54       * Run the side effect. Any thrown exception gets "chucked" so that you may
55       * catch them as is. See {@link org.opencastproject.util.data.functions.Functions#chuck(Throwable)} for details.
56       */
57      protected abstract void xrun() throws Exception;
58    }
59  }