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1   /**
2    * This file Copyright (c) 2013-2018 Magnolia International
3    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
4    *
5    *
6    * This file is dual-licensed under both the Magnolia
7    * Network Agreement and the GNU General Public License.
8    * You may elect to use one or the other of these licenses.
9    *
10   * This file is distributed in the hope that it will be
11   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12   * implied warranty of MERCHANTABILITY or FITNESS FOR A
13   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14   * Redistribution, except as permitted by whichever of the GPL
15   * or MNA you select, is prohibited.
16   *
17   * 1. For the GPL license (GPL), you can redistribute and/or
18   * modify this file under the terms of the GNU General
19   * Public License, Version 3, as published by the Free Software
20   * Foundation.  You should have received a copy of the GNU
21   * General Public License, Version 3 along with this program;
22   * if not, write to the Free Software Foundation, Inc., 51
23   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24   *
25   * 2. For the Magnolia Network Agreement (MNA), this file
26   * and the accompanying materials are made available under the
27   * terms of the MNA which accompanies this distribution, and
28   * is available at http://www.magnolia-cms.com/mna.html
29   *
30   * Any modifications to this file must keep this entire header
31   * intact.
32   *
33   */
34  package info.magnolia.ui.api.action;
35  
36  
37  /**
38   * Responsible for executing actions, doing lookups of action definitions based on action names and evaluating if an
39   * action is available. Creates a new instance of the action for each execution and allows the action to receive its
40   * action definition object and all parameters given through injection as it is created.
41   *
42   * @see Action
43   * @see ActionDefinition
44   */
45  public interface ActionExecutor {
46  
47      /**
48       * Creates a new instance of the action for the supplied name and executes it. The arguments passed here along with
49       * the action definition are made available to the action instance using injection.
50       *
51       * @throws ActionExecutionException if the action encounters a problem during execution or if no action definition matches the name
52       */
53      void execute(String actionName, Object... args) throws ActionExecutionException;
54  
55      /**
56       * Performs a lookup for an action definition by name.
57       *
58       * @return the action definition for the supplied action name or null if not found
59       */
60      ActionDefinition getActionDefinition(String actionName);
61  
62      /**
63       * Action executor implementation that does nothing.
64       */
65      class Noop implements ActionExecutor {
66  
67          @Override
68          public void execute(String actionName, Object... args) throws ActionExecutionException {
69              // do nothing
70          }
71  
72          @Override
73          public ActionDefinition getActionDefinition(String actionName) {
74              throw new UnsupportedOperationException("This is a noop implementation for ActionExecutor");
75          }
76      }
77  }