bundles/org.simantics.databoard/src/org/simantics/databoard/accessor/binary/BinaryBoolean.java

   1 /*******************************************************************************
   2  *  Copyright (c) 2010 Association for Decentralized Information Management in
   3  *  Industry THTH ry.
   4  *  All rights reserved. This program and the accompanying materials
   5  *  are made available under the terms of the Eclipse Public License v1.0
   6  *  which accompanies this distribution, and is available at
   7  *  http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  *  Contributors:
  10  *      VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.databoard.accessor.binary;
  13
  14 import java.io.IOException;
  15
  16 import org.simantics.databoard.Bindings;
  17 import org.simantics.databoard.accessor.Accessor;
  18 import org.simantics.databoard.accessor.BooleanAccessor;
  19 import org.simantics.databoard.accessor.error.AccessorConstructionException;
  20 import org.simantics.databoard.accessor.error.AccessorException;
  21 import org.simantics.databoard.accessor.error.ReferenceException;
  22 import org.simantics.databoard.accessor.event.Event;
  23 import org.simantics.databoard.accessor.event.ValueAssigned;
  24 import org.simantics.databoard.accessor.file.FileBooleanAccessor;
  25 import org.simantics.databoard.accessor.impl.AccessorParams;
  26 import org.simantics.databoard.accessor.impl.ListenerEntry;
  27 import org.simantics.databoard.accessor.interestset.BooleanInterestSet;
  28 import org.simantics.databoard.accessor.reference.ChildReference;
  29 import org.simantics.databoard.binding.Binding;
  30 import org.simantics.databoard.binding.BooleanBinding;
  31 import org.simantics.databoard.binding.error.BindingException;
  32 import org.simantics.databoard.type.BooleanType;
  33 import org.simantics.databoard.util.binary.Blob;
  34
  35 public class BinaryBoolean extends BinaryObject implements BooleanAccessor, FileBooleanAccessor {
  36
  37         public BinaryBoolean(BinaryObject parent, Blob blob, BooleanType type, AccessorParams params)
  38         throws AccessorConstructionException {
  39                 super(parent, blob, type, params);
  40                 try {
  41                         blob.setLength(1L);
  42                 } catch (IOException e) {
  43                         throw new AccessorConstructionException(e);
  44                 }
  45         }
  46
  47         @Override
  48         public BooleanType type() {
  49                 return (BooleanType) type;
  50         }
  51
  52         @Override
  53         public boolean getValue() throws AccessorException {
  54                 assert b.isOpen();
  55                 readLock();
  56                 try {
  57                         b.position(0L);
  58                         byte v = b.readByte();
  59                         if (v==0) return false;
  60                         if (v==1) return true;
  61                         throw new AccessorException("Unexpected value "+v+", expected 0 or 1 for Boolean");
  62                 } catch (IOException e) {
  63                         throw new AccessorException(e);
  64                 } finally {
  65                         readUnlock();
  66                 }
  67         }
  68
  69         @Override
  70         Event applyLocal(Event e, boolean makeRollback) throws AccessorException {
  71                 Event rollback = makeRollback ? new ValueAssigned( Bindings.BOOLEAN, getValue() ) : null;
  72                 if (e instanceof ValueAssigned) {
  73                         ValueAssigned va = (ValueAssigned) e;
  74                         if (va.newValue == null) throw new AccessorException("Boolean value expected, got null");
  75                         setValueNoflush(va.newValue.getBinding(), va.newValue.getValue());
  76                         return rollback;
  77                 } else {
  78                         throw new AccessorException("Cannot apply "+e.getClass().getName()+" to Boolean");
  79                 }
  80         }
  81
  82         @SuppressWarnings("unchecked")
  83         @Override
  84         public <T extends Accessor> T getComponent(ChildReference reference)
  85                         throws AccessorConstructionException {
  86                 if (reference==null) return (T) this;
  87                 throw new ReferenceException(reference.getClass()+" is not a subreference of BooleanType");
  88         }
  89
  90
  91         @Override
  92         public Object getValue(Binding binding) throws AccessorException {
  93                 assert b.isOpen();
  94                 readLock();
  95                 try {
  96                         BooleanBinding bb = (BooleanBinding) binding;
  97                         boolean v = getValue();
  98                         return bb.create(v);
  99                 } catch(BindingException e) {
 100                         throw new AccessorException(e);
 101                 } finally {
 102                         readUnlock();
 103                 }
 104         }
 105
 106         public void setValueNoflush(boolean newValue) throws AccessorException {
 107                 assert b.isOpen();
 108                 writeLock();
 109                 try {
 110                         // Set value
 111                         b.position(0);
 112                         b.write( newValue ? (byte) 1 : (byte) 0 );
 113
 114                         // Notify
 115                         ListenerEntry le = listeners;
 116                         while (le!=null) {
 117                                 BooleanInterestSet is = le.getInterestSet();
 118                                 if (is.inNotifications()) {
 119                                         Event e = new ValueAssigned( Bindings.BOOLEAN, is.inValues() ? newValue : null );
 120                                         emitEvent(le, e);
 121                                 }
 122                                 le = le.next;
 123                         }
 124
 125                 } catch (IOException e) {
 126                         throw new AccessorException(e);
 127                 } finally {
 128                         writeUnlock();
 129                 }
 130         }
 131
 132         @Override
 133         public void setValue(boolean newValue) throws AccessorException {
 134                 assert b.isOpen();
 135                 writeLock();
 136                 try {
 137                         setValueNoflush(newValue);
 138                         b.flush();
 139                 } catch (IOException e) {
 140                         throw new AccessorException(e);
 141                 } finally {
 142                         writeUnlock();
 143                 }
 144         }
 145
 146         @Override
 147         public void setValueNoflush(Binding binding, Object newValue)
 148                         throws AccessorException {
 149                 assert b.isOpen();
 150                 writeLock();
 151                 try {
 152                         boolean nv = ((BooleanBinding)binding).getValue_(newValue);
 153                         setValueNoflush(nv);
 154                 } catch (BindingException e) {
 155                         throw new AccessorException(e);
 156                 } finally {
 157                         writeUnlock();
 158                 }
 159         }
 160
 161 }
 162