bundles/org.simantics.databoard/src/org/simantics/databoard/accessor/impl/MapAccessorIterator.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007 VTT Technical Research Centre of Finland and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/epl-v10.html
   7  *
   8  * Contributors:
   9  *     VTT Technical Research Centre of Finland - initial API and implementation
  10  *******************************************************************************/
  11 package org.simantics.databoard.accessor.impl;
  12
  13 import org.simantics.databoard.Bindings;
  14 import org.simantics.databoard.accessor.MapAccessor;
  15 import org.simantics.databoard.accessor.error.AccessorException;
  16 import org.simantics.databoard.binding.ArrayBinding;
  17 import org.simantics.databoard.binding.Binding;
  18 import org.simantics.databoard.binding.BooleanBinding;
  19 import org.simantics.databoard.binding.NumberBinding;
  20 import org.simantics.databoard.binding.error.BindingException;
  21 import org.simantics.databoard.binding.impl.BooleanArrayBinding;
  22 import org.simantics.databoard.binding.impl.ByteArrayBinding;
  23 import org.simantics.databoard.binding.impl.DoubleArrayBinding;
  24 import org.simantics.databoard.binding.impl.FloatArrayBinding;
  25 import org.simantics.databoard.binding.impl.IntArrayBinding;
  26 import org.simantics.databoard.binding.impl.LongArrayBinding;
  27 import org.simantics.databoard.type.ArrayType;
  28 import org.simantics.databoard.util.Limit;
  29 import org.simantics.databoard.util.Range;
  30
  31 /**
  32  * This helper class creates an iterator to MapAccessor
  33  *
  34  * @param <K> key class
  35  * @param <V> value class
  36  * @author Toni Kalajainen <toni.kalajainen@vtt.fi>
  37  */
  38 public class MapAccessorIterator<K, V> {
  39
  40         MapAccessor map;
  41         Binding keyBinding;
  42         Binding valueBinding;
  43
  44         Object from;
  45         boolean fromInclusive;
  46
  47         Object end;
  48         boolean endInclusive;
  49
  50         ArrayBinding keyCacheBinding;
  51         Object keyCache;
  52
  53         ArrayBinding valueCacheBinding;
  54         Object valueCache;
  55
  56         // Entry index, i.e. the number of entries read starting from 0
  57         int index = -1;
  58
  59         // The number of samples written to cache
  60         int samplesInCache = 0;
  61
  62         // The index in cache
  63         int cacheIndex = -1;
  64
  65         /**
  66          * Initialize iterator with a cache. The cache should already be allocated with some empty elements.
  67          * @param map
  68          * @param keyBinding
  69          * @param from
  70          * @param fromInclusive
  71          * @param end
  72          * @param endInclusive
  73          * @param keyCacheBinding
  74          * @param keyCache
  75          * @param valueCacheBinding
  76          * @param valueCache
  77          */
  78         public MapAccessorIterator(
  79                         MapAccessor map,
  80                         Binding keyBinding, Object from, boolean fromInclusive, Object end, boolean endInclusive,
  81                         ArrayBinding keyCacheBinding, Object keyCache,
  82                         ArrayBinding valueCacheBinding, Object valueCache) {
  83                 this.map = map;
  84                 this.keyBinding = keyBinding;
  85                 this.from = from;
  86                 this.fromInclusive = fromInclusive;
  87                 this.end = end;
  88                 this.endInclusive = endInclusive;
  89                 this.valueBinding = valueCacheBinding.getComponentBinding();
  90                 this.keyCacheBinding = keyCacheBinding;
  91                 this.keyCache = keyCache;
  92                 this.valueCacheBinding = valueCacheBinding;
  93                 this.valueCache = valueCache;
  94         }
  95
  96         /**
  97          * Initialize map accessor iterator with a default cache
  98          * @param map
  99          * @param keyBinding
 100          * @param from
 101          * @param fromInclusive
 102          * @param end
 103          * @param endInclusive
 104          * @param valueBinding
 105          * @param cacheSize
 106          * @throws BindingException
 107          * @throws AccessorException
 108          */
 109         public MapAccessorIterator(
 110                         MapAccessor map,
 111                         Binding keyBinding, Object from, boolean fromInclusive, Object end, boolean endInclusive,
 112                         Binding valueBinding,
 113                         int cacheSize) throws BindingException, AccessorException {
 114                 this.map = map;
 115                 this.keyBinding = keyBinding;
 116                 this.from = from;
 117                 this.fromInclusive = fromInclusive;
 118                 this.end = end;
 119                 this.endInclusive = endInclusive;
 120                 this.valueBinding = valueBinding;
 121
 122                 // TODO calc num of elements if source
 123 //              int count = map.count(keyBinding, from, fromInclusive, end, endInclusive);
 124 //              int len = Math.min(count, 256);
 125                 Range range = new Range(Limit.inclusive(cacheSize), Limit.nolimit());
 126                 this.keyCacheBinding = Bindings.getBinding( new ArrayType(keyBinding.type(), range) );
 127                 this.keyCache = keyCacheBinding.createDefault();
 128                 this.valueCacheBinding = Bindings.getBinding( new ArrayType(valueBinding.type(), range) );
 129                 this.valueCache = valueCacheBinding.createDefault();
 130         }
 131
 132     /**
 133          * Reads data to cache.
 134          *
 135          * Updates from and fromInclusive fields for next read.
 136          * Updates samplesInCache field.
 137          * Sets cacheIndex to 0.
 138          *
 139          * @throws AccessorException
 140          */
 141         private void fillCache() throws AccessorException {
 142                 try {
 143                         int limit = Math.min(keyCacheBinding.size(keyCache), valueCacheBinding.size(valueCache));
 144                         if (limit==0) throw new AccessorException("You should have some entries in the cache");
 145
 146                         cacheIndex = -1;
 147
 148                         if (from==null) {
 149                                 samplesInCache = 0;
 150                                 return;
 151                         }
 152
 153                         samplesInCache = map.getEntries(
 154                                 keyBinding, from, fromInclusive,
 155                                 end, endInclusive,
 156                                 keyCacheBinding, keyCache,
 157                                 valueCacheBinding, valueCache,
 158                                 limit);
 159
 160                         if (samplesInCache==0) {
 161                                 from = null;
 162                                 return;
 163                         }
 164
 165                         from = keyCacheBinding.get(keyCache, samplesInCache-1);
 166                         fromInclusive = false;
 167                 } catch (BindingException e) {
 168                         throw new AccessorException(e);
 169                 }
 170         }
 171
 172         public boolean hasNext() throws AccessorException {
 173                 if (from==null) return false;
 174                 if (cacheIndex>=samplesInCache-1) fillCache();
 175                 if (cacheIndex>=samplesInCache-1) return false;
 176                 return cacheIndex+1<samplesInCache;
 177         }
 178
 179         public boolean next() throws AccessorException {
 180                 if (from==null) return false;
 181                 if (cacheIndex>=samplesInCache-1) fillCache();
 182                 if (cacheIndex>=samplesInCache-1) return false;
 183                 cacheIndex++;
 184                 index++;
 185                 return true;
 186         }
 187
 188         @SuppressWarnings("unchecked")
 189         public K key() throws AccessorException {
 190                 try {
 191                         return (K) keyCacheBinding.get(keyCache, cacheIndex);
 192                 } catch (IndexOutOfBoundsException e) {
 193                         throw new AccessorException(e);
 194                 } catch (BindingException e) {
 195                         throw new AccessorException(e);
 196                 }
 197         }
 198
 199         @SuppressWarnings("unchecked")
 200         public V value() throws AccessorException {
 201                 try {
 202                         return (V) valueCacheBinding.get(valueCache, cacheIndex);
 203                 } catch (IndexOutOfBoundsException e) {
 204                         throw new AccessorException(e);
 205                 } catch (BindingException e) {
 206                         throw new AccessorException(e);
 207                 }
 208         }
 209
 210         public double keyDouble() throws AccessorException {
 211                 try {
 212                         if (keyCacheBinding instanceof FloatArrayBinding) {
 213                                 return ((float[]) keyCache)[cacheIndex];
 214                         }
 215                         if (keyCacheBinding instanceof DoubleArrayBinding) {
 216                                 return ((double[]) keyCache)[cacheIndex];
 217                         }
 218                         if (keyCacheBinding instanceof ByteArrayBinding) {
 219                                 return ((byte[]) keyCache)[cacheIndex];
 220                         }
 221                         if (keyCacheBinding instanceof IntArrayBinding) {
 222                                 return ((int[]) keyCache)[cacheIndex];
 223                         }
 224                         if (keyCacheBinding instanceof LongArrayBinding) {
 225                                 return ((long[]) keyCache)[cacheIndex];
 226                         }
 227                         if (keyCacheBinding instanceof BooleanArrayBinding) {
 228                                 return ((boolean[]) keyCache)[cacheIndex] ? 1.0 : 0.0;
 229                         }
 230                         Object o = keyCacheBinding.get(keyCache, cacheIndex);
 231                         Binding b = keyCacheBinding.getComponentBinding();
 232                         if (b instanceof BooleanBinding)
 233                                 return ((BooleanBinding)b).getValue(o) ? 1.0 : 0.0;
 234                         NumberBinding nb = (NumberBinding) b;
 235                         return nb.getValue(o).doubleValue();
 236                 } catch (IndexOutOfBoundsException e) {
 237                         throw new AccessorException(e);
 238                 } catch (BindingException e) {
 239                         throw new AccessorException(e);
 240                 }
 241         }
 242
 243         public double valueDouble() throws AccessorException {
 244                 try {
 245                         if (valueCacheBinding instanceof FloatArrayBinding) {
 246                                 return ((float[]) valueCache)[cacheIndex];
 247                         }
 248                         if (valueCacheBinding instanceof DoubleArrayBinding) {
 249                                 return ((double[]) valueCache)[cacheIndex];
 250                         }
 251                         if (valueCacheBinding instanceof ByteArrayBinding) {
 252                                 return ((byte[]) valueCache)[cacheIndex];
 253                         }
 254                         if (valueCacheBinding instanceof IntArrayBinding) {
 255                                 return ((int[]) valueCache)[cacheIndex];
 256                         }
 257                         if (valueCacheBinding instanceof LongArrayBinding) {
 258                                 return ((long[]) valueCache)[cacheIndex];
 259                         }
 260                         if (valueCacheBinding instanceof BooleanArrayBinding) {
 261                                 return ((boolean[]) valueCache)[cacheIndex] ? 1.0 : 0.0;
 262                         }
 263                         Object o = valueCacheBinding.get(valueCache, cacheIndex);
 264                         Binding b = valueCacheBinding.getComponentBinding();
 265                         if (b instanceof BooleanBinding)
 266                                 return ((BooleanBinding)b).getValue(o) ? 1.0 : 0.0;
 267                         NumberBinding nb = (NumberBinding) b;
 268                         return nb.getValue(o).doubleValue();
 269                 } catch (IndexOutOfBoundsException e) {
 270                         throw new AccessorException(e);
 271                 } catch (BindingException e) {
 272                         throw new AccessorException(e);
 273                 }
 274         }
 275
 276         public int index() {
 277                 return index;
 278         }
 279
 280 }
 281