001package votorola.g.hold; // Copyright 2005-2006, Michael Allan. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Votorola Software"), to deal in the Votorola Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicence, and/or sell copies of the Votorola Software, and to permit persons to whom the Votorola Software is furnished to do so, subject to the following conditions: The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Votorola Software. THE VOTOROLA SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE VOTOROLA SOFTWARE OR THE USE OR OTHER DEALINGS IN THE VOTOROLA SOFTWARE. 002 003import java.util.*; 004import java.util.concurrent.atomic.AtomicBoolean; 005import votorola.g.lang.*; 006 007 008/** A thread-safe implementation of a spool based on a Vector. 009 */ 010public final @ThreadSafe class SpoolT extends Vector<Hold> implements Spool // better to extend Vector by composition, cf. Spool1 011{ 012 013 014 // - C o l l e c t i o n -------------------------------------------------------------- 015 016 017 public boolean addAll( int index, Collection<? extends Hold> c ) { throw new UnsupportedOperationException(); } // no need 018 019 020 021 // - L i s t -------------------------------------------------------------------------- 022 023 024 public void add( int index, Hold hold ) { throw new UnsupportedOperationException(); } // no need 025 026 027 public List<Hold> subList( int fromIndex, int toIndex ) { throw new UnsupportedOperationException(); } // back door to bypass add(Hold) 028 029 030 031 // - S p o o l ------------------------------------------------------------------------ 032 033 034 public boolean isUnwinding() { return isUnwindingA.get(); } 035 036 037 private final AtomicBoolean isUnwindingA = new AtomicBoolean(); 038 039 040 041 public boolean unwind() { return unwind( CATCHER_0 ); } 042 043 044 045 public boolean unwind( Catcher<Hold> catcher ) 046 { 047 if( isUnwindingA.getAndSet( true )) return false; 048 049 for( ;; ) 050 { 051 final Hold hold; 052 synchronized( SpoolT.this ) // atomic test/remove, since other threads may be calling remove() 053 { 054 if( isEmpty() ) break; 055 056 hold = remove( size() - 1 ); 057 } 058 try{ hold.release(); } 059 catch( Error r ) { catcher.catchError( hold, r ); } 060 catch( Exception x ) { catcher.catchException( hold, x ); } 061 } 062 return true; 063 } 064 065 066 067 // - V e c t o r ---------------------------------------------------------------------- 068 069 070 public void addElement( Hold hold ) { throw new UnsupportedOperationException(); } // no need 071 072 073 public void insertElementAt( Hold hold, int index ) { throw new UnsupportedOperationException(); } // no need 074 075 076 077}