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21 
22 
23 
24 // __________ Imports __________
25 
26 import com.sun.star.uno.UnoRuntime;
27 
28 import java.lang.*;
29 import java.util.*;
30 
31 // __________ Implementation __________
32 
33 /**
34  * It's implement a static container which hold
35  * all opened documents and her views alive.
36  * It's possible to register/deregister such views,
37  * to get information about these and it provides
38  * some global functionality - like termination of
39  * this demo application.
40  *
41  * @author     Andreas Schlüns
42  * @created    01.03.2002 08:42
43  */
44 public class ViewContainer extends Thread
45 {
46     // ____________________
47 
48     /**
49      * provides a singleton view container
50      * Neccessary for terminate(9 functionality to be able
51      * to call Runtime.runFinilization().
52      *
53      * @return a reference to the singleton ViewContainer instance
54      */
getGlobalContainer()55     public static synchronized ViewContainer getGlobalContainer()
56     {
57         if (maSingleton==null)
58             maSingleton=new ViewContainer();
59         return maSingleton;
60     }
61 
62     // ____________________
63 
64     /**
65      * ctor
66      * It's private - because nobody should create any instance
67      * expect the only global one, which wil be created by ourself!
68      */
ViewContainer()69     private ViewContainer()
70     {
71         mlViews          = new Vector();
72         mlListener       = new Vector();
73         mbShutdownActive = false       ;
74         Runtime.getRuntime().addShutdownHook(this);
75     }
76 
77     // ____________________
78 
79     /**
80      * This register a new view inside this global container
81      * (if it doesnt already exist).
82      *
83      * @param   aView       view which whish to be registered inside this container
84      */
addView(Object aView)85     public void addView(Object aView)
86     {
87         synchronized(mlViews)
88         {
89             if(mlViews.contains(aView)==false)
90                 mlViews.add(aView);
91         }
92     }
93 
94     // ____________________
95 
96     /**
97      * This deregister a view from this global container.
98      * Normaly it should be the last reference to the view
99      * and her finalize() method should be called.
100      * If last view will be closed here - we terminate these
101      * java application too. Because there is no further
102      * visible frame anymore.
103      *
104      * @param aView
105      *          view object which wish to be deregistered
106      */
removeView(Object aView)107     public void removeView(Object aView)
108     {
109         int nViewCount = 0;
110         synchronized(mlViews)
111         {
112             if(mlViews.contains(aView)==true)
113                 mlViews.remove(aView);
114 
115             nViewCount = mlViews.size();
116 
117             if (nViewCount<1)
118                 mlViews = null;
119         }
120         // If this view is a registered shutdown listener on this view container
121         // too, we must call his interface and forget him as possible listener.
122         // It's neccessary to guarantee his dead ...
123         boolean bShutdownView = false;
124         synchronized(mlListener)
125         {
126             bShutdownView = mlListener.contains(aView);
127             if (bShutdownView==true)
128                 mlListener.remove(aView);
129         }
130         if (bShutdownView==true)
131             ((IShutdownListener)aView).shutdown();
132 
133         // We use a system.exit() to finish the whole application.
134         // And further we have registered THIS instance as a possible shutdown
135         // hook at the runtime class. So our run() method will be called.
136         // Teh our view container should be empty - but
137         // our listener container can include some references.
138         // These objects wich to be informed then and release e.g. some
139         // remote references.
140         if (nViewCount<1)
141         {
142             boolean bNeccessary = false;
143             synchronized(this)
144             {
145                 bNeccessary = ! mbShutdownActive;
146             }
147             if (bNeccessary==true)
148             {
149                 System.out.println("call exit(0)!");
150                 System.exit(0);
151             }
152         }
153     }
154 
155     // ____________________
156 
157     /**
158      * add/remove listener for possibe shutdown events
159      */
addListener( IShutdownListener rListener )160     public void addListener( IShutdownListener rListener )
161     {
162         synchronized(mlListener)
163         {
164             if ( ! mlListener.contains(rListener) )
165                 mlListener.add(rListener);
166         }
167     }
168 
169     // ____________________
170 
removeListener( IShutdownListener rListener )171     public void removeListener( IShutdownListener rListener )
172     {
173         synchronized(mlListener)
174         {
175             if ( mlListener.contains(rListener) )
176                 mlListener.remove(rListener);
177         }
178     }
179 
180     // ____________________
181 
182     /**
183      * Is called from current runtime system of the java machine
184      * on shutdown. We inform all current registered listener and
185      * views. They should deinitialize her internal things then.
186      */
run()187     public void run()
188     {
189         synchronized(this)
190         {
191             if (mbShutdownActive)
192                 return;
193             mbShutdownActive=true;
194         }
195 
196         while( true )
197         {
198             IShutdownListener aListener = null;
199             synchronized(mlListener)
200             {
201                 try{
202                     aListener = (IShutdownListener)mlListener.firstElement();
203                 } catch(java.util.NoSuchElementException exEmpty) {}
204             }
205             if (aListener==null)
206                 break;
207 
208             aListener.shutdown();
209             // May this listener has dergeistered himself.
210             // But if not we must do it for him. Our own
211             // method "removeListener()" ignore requests for
212             // already gone listener objects.
213             removeListener(aListener);
214         }
215 
216         if (mlViews!=null)
217         {
218             synchronized(mlViews)
219             {
220                 mlViews.clear();
221                 mlViews = null;
222             }
223         }
224 
225         if (mlListener!=null)
226         {
227             synchronized(mlListener)
228             {
229                 mlListener.clear();
230                 mlListener = null;
231             }
232         }
233     }
234 
235     // ____________________
236 
237     /**
238      * @const   BASICNAME   it's used to create uinque names for all regieterd views
239      */
240     private static final String BASICNAME = "Document View ";
241 
242     // ____________________
243 
244     /**
245      * @member  mbInplace           indicates using of inplace office frames instead of outplace ones
246      * @member  maSingleton         singleton instance of this view container
247      * @member  mlViews             list of all currently registered document views
248      * @member  mlListener          list of all currently registered shutdown listener
249      * @member  mbShutdownActive    if this shutdown hook already was started it's not a good idea to
250      *                              call System.exit() again for other conditions.
251      *                              We supress it by using this variable!
252      */
253     public  static boolean       mbInplace   = false ;
254     private static ViewContainer maSingleton = null  ;
255     private        Vector        mlViews             ;
256     private        Vector        mlListener          ;
257     private        boolean       mbShutdownActive    ;
258 }
259