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    1   /*
    2    *
    3    *   Copyright 2005 The Apache Software Foundation.
    4    *
    5    *  Licensed under the Apache License, Version 2.0 (the "License");
    6    *  you may not use this file except in compliance with the License.
    7    *  You may obtain a copy of the License at
    8    *
    9    *      http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   *  Unless required by applicable law or agreed to in writing, software
    12   *  distributed under the License is distributed on an "AS IS" BASIS,
    13   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   *  See the License for the specific language governing permissions and
    15   *  limitations under the License.
    16   *
    17   */
    18  package org.apache.commons.scxml;
    19
    20  import java.util.ArrayList;
    21  import java.util.HashSet;
    22  import java.util.Iterator;
    23  import java.util.Set;
    24  import java.util.Collection;
    25
    26  import org.apache.commons.scxml.model.State;
    27
    28  /***
    29   * The encapsulation of the current state of a state machine.
    30   *
    31   */
    32  public class Status {
    33
    34      /***
    35       * The states that are currently active.
    36       */
    37      private Set states;
    38
    39      /***
    40       * The events that are currently queued.
    41       */
    42      private Collection events;
    43
    44      /***
    45       * Have we reached a final configuration for this state machine.
    46       *
    47       * True - if all the states are final and there are not events
    48       * pending from the last step. False - otherwise.
    49       *
    50       * @return Whether a final configuration has been reached.
    51       */
    52      public boolean isFinal() {
    53          boolean rslt = true;
    54          for (Iterator i = states.iterator(); i.hasNext();) {
    55              State s = (State) i.next();
    56              if (!s.getIsFinal()) {
    57                  rslt = false;
    58                  break;
    59              }
    60              //the status is final only iff these are top-level states
    61              if (s.getParent() != null) {
    62                  rslt = false;
    63                  break;
    64              }
    65          }
    66          if (!events.isEmpty()) {
    67              rslt = false;
    68          }
    69          return rslt;
    70      }
    71
    72      /***
    73       * Constructor.
    74       */
    75      public Status() {
    76          states = new HashSet();
    77          events = new ArrayList();
    78      }
    79
    80      /***
    81       * Get the states configuration (leaf only).
    82       *
    83       * @return Returns the states configuration - simple (leaf) states only.
    84       */
    85      public Set getStates() {
    86          return states;
    87      }
    88
    89      /***
    90       * Get the events that are currently queued.
    91       *
    92       * @return The events that are currently queued.
    93       */
    94      public Collection getEvents() {
    95          return events;
    96      }
    97
    98      /***
    99       * Get the complete states configuration.
    100      *
    101      * @return complete states configuration including simple states and their
    102      *         complex ancestors up to the root.
    103      */
    104     public Set getAllStates() {
    105         return SCXMLHelper.getAncestorClosure(states, null);
    106     }
    107
    108 }
    109