2009/05/20 - Apache Shale has been retired.

   /*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to you 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 org.apache.shale.dialog.basic;
  
  import java.io.Serializable;
  import java.util.Map;
  
  import javax.faces.context.FacesContext;
  
  import org.apache.shale.dialog.basic.model.Dialog;
  import org.apache.shale.dialog.basic.model.State;
  
  /***
   * <p>JavaBean that represents the current {@link State} within
   * a {@link Dialog}.</p>
   */
  class Position implements Serializable {
  
  
      // ------------------------------------------------------------ Constructors
  
  
      /***
       * Serial version UID.
       */
      private static final long serialVersionUID = -1600336297791202073L;
  
  
      /***
       * <p>Construct a new {@link Position} representing the specified
       * {@link State} for the specified {@link Dialog}, and associated
       * with the specified <code>data</code> instance.</p>
       *
       * @param dialog {@link Dialog} to be recorded
       * @param state {@link State} to be recorded
       * @param data Data instance to be recorded
       */
      Position(Dialog dialog, State state, java.lang.Object data) {
          if (dialog == null) {
              throw new IllegalArgumentException("Dialog cannot be null");
          }
          setDialog(dialog);
          setState(state);
          setData(data);
      }
  
  
      // ------------------------------------------------------ Instance Variables
  
  
      /***
       * <p>The data instance for the dialog execution represeented by this
       * {@link Position}.</p>
       */
      private Object data = null;
  
  
      /***
       * <p>The {@link Dialog} within which this {@link Position} is reported.
       * This value is transient, and may need to be regenerated.</p>
       */
      private transient Dialog dialog = null;
  
  
      /***
       * <p>The name of the {@link Dialog} within which this {@link Position}
       * is reported.</p>
       */
      private String dialogName = null;
  
  
      /***
       * <p>The {@link State} that represents the current position within the
       * {@link Dialog} that is being executed.  This value is transient, and
       * may need to be regenerated.</p>
       */
      private transient State state = null;
  
  
      /***
       * <p>The name of the {@link State} that represents the current position
       * within the {@link Dialog} that is being executed.</p>
       */
      private String stateName = null;
 
 
     // ------------------------------------------------------ Package Properties
 
 
     /***
      * <p>Return the data object associated with this dialog execution.</p>
      *
      * @return The associated data object for this dialog instance
      */
     Object getData() {
         return this.data;
     }
 
 
     /***
      * <p>Set the data object associated with this dialog execution.</p>
      *
      * @param data The new data object
      */
     void setData(Object data) {
         this.data = data;
     }
 
 
     /***
      * <p>Return the {@link Dialog} whose execution is tracked by this
      * {@link Position}.</p>
      *
      * @return The {@link Dialog} being tracked by this {@link Position}
      *         instance
      */
     Dialog getDialog() {
         if (this.dialog != null) {
             return this.dialog;
         }
         Map map = (Map)
           FacesContext.getCurrentInstance().getExternalContext().
           getApplicationMap().get(Globals.DIALOGS);
         this.dialog = (Dialog) map.get(this.dialogName);
         return this.dialog;
     }
 
 
     /***
      * <p>Set the {@link Dialog} whose execution is being tracked by this
      * {@link Position}.</p>
      *
      * @param dialog The {@link Dialog} instance being tracked
      */
     private void setDialog(Dialog dialog) {
         this.dialog = dialog;
         this.dialogName = dialog.getName();
     }
 
 
     /***
      * <p>Return the {@link State} representing the current execution position
      * within the owning {@link Dialog}.</p>
      *
      * @return The current {@link State} within the owning {@link Dialog}
      */
     State getState() {
         if (this.state == null) {
             Dialog dialog = getDialog();
             if (dialog == null) {
                 return null;
             }
             this.state = dialog.findState(this.stateName);
         }
         return this.state;
     }
 
 
     /***
      * <p>Set the {@link State} representing the current execution position
      * within the owning {@link Dialog}.</p>
      *
      * @param state The new {@link State}
      */
     void setState(State state) {
         if (state == null) {
             this.state = null;
             this.stateName = null;
         } else {
             this.state = state;
             this.stateName = state.getName();
         }
     }
 
 
     // ---------------------------------------------------------- Public Methods
 
 
     /***
      * <p>Return a String representation of this object.</p>
      *
      * @return The String representation of this {@link Position} instance
      */
     public String toString() {
         if (getState() == null) {
             return "Position[dialog=" + getDialog().getName()
             + ",data=" + getData() + "]";
         } else {
             return "Position[dialog=" + getDialog().getName()
                    + ",state=" + getState().getName()
                    + ",data=" + getData() + "]";
         }
     }
 
 
 }