analysis/org.eclipse.tracecompass.analysis.timing.core/src/org/eclipse/tracecompass/internal/analysis/timing/core/store/ArrayListStore.java

   1 /*******************************************************************************
   2  * Copyright (c) 2016 Ericsson
   3  *
   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
  10 package org.eclipse.tracecompass.internal.analysis.timing.core.store;
  11
  12 import static org.eclipse.tracecompass.common.core.NonNullUtils.checkNotNull;
  13
  14 import java.util.ArrayList;
  15 import java.util.Collection;
  16 import java.util.Collections;
  17 import java.util.Comparator;
  18 import java.util.Iterator;
  19 import java.util.List;
  20 import java.util.concurrent.locks.ReadWriteLock;
  21 import java.util.concurrent.locks.ReentrantReadWriteLock;
  22 import java.util.stream.Collectors;
  23
  24 import org.eclipse.jdt.annotation.NonNull;
  25 import org.eclipse.jdt.annotation.Nullable;
  26 import org.eclipse.tracecompass.segmentstore.core.ISegment;
  27 import org.eclipse.tracecompass.segmentstore.core.ISegmentStore;
  28
  29 import com.google.common.collect.ImmutableList;
  30
  31 /**
  32  * Implementation of an {@link ISegmentStore} using one in-memory
  33  * {@link ArrayList}. This relatively simple implementation holds everything in
  34  * memory, and as such cannot contain too much data.
  35  *
  36  * The ArrayListStore itself is {@link Iterable}, and its iteration order will
  37  * be by ascending order of start times. For segments with identical start
  38  * times, the secondary comparator will be the end time. If even those are
  39  * equal, it will defer to the segments' natural ordering (
  40  * {@link ISegment#compareTo}).
  41  *
  42  * The store's tree maps will not accept duplicate key-value pairs, which means
  43  * that if you want several segments with the same start and end times, make
  44  * sure their compareTo() differentiates them.
  45  *
  46  * Removal operations are not supported.
  47  *
  48  * @param <E>
  49  *            The type of segment held in this store
  50  *
  51  * @author Matthew Khouzam
  52  */
  53 public class ArrayListStore<@NonNull E extends ISegment> implements ISegmentStore<E> {
  54
  55     private final Comparator<E> COMPARATOR = (o1, o2) -> {
  56         int ret = Long.compare(o1.getStart(), o2.getStart());
  57         if (ret == 0) {
  58             return Long.compare(o1.getEnd(), o2.getEnd());
  59         }
  60         return ret;
  61     };
  62
  63     private final ReadWriteLock fLock = new ReentrantReadWriteLock(false);
  64
  65     private final List<E> fStore;
  66
  67     private @Nullable transient Iterable<E> fLastSnapshot = null;
  68
  69     /**
  70      * Constructor
  71      */
  72     public ArrayListStore() {
  73         fStore = new ArrayList<>();
  74     }
  75
  76     /**
  77      * Constructor
  78      *
  79      * @param array
  80      *            an array of elements to wrap in the segment store
  81      *
  82      */
  83     public ArrayListStore(Object[] array) {
  84         fStore = new ArrayList<>();
  85         for (int i = 0; i < array.length; i++) {
  86             if (array[i] instanceof ISegment) {
  87                 fStore.add((E) array[i]);
  88             }
  89         }
  90         fStore.sort(COMPARATOR);
  91     }
  92     // ------------------------------------------------------------------------
  93     // Methods from Collection
  94     // ------------------------------------------------------------------------
  95
  96     @Override
  97     public Iterator<E> iterator() {
  98         fLock.readLock().lock();
  99         try {
 100             Iterable<E> lastSnapshot = fLastSnapshot;
 101             if (lastSnapshot == null) {
 102                 lastSnapshot = ImmutableList.copyOf(fStore);
 103                 fLastSnapshot = lastSnapshot;
 104             }
 105             return checkNotNull(lastSnapshot.iterator());
 106         } finally {
 107             fLock.readLock().unlock();
 108         }
 109     }
 110
 111     @Override
 112     public boolean add(@Nullable E val) {
 113         if (val == null) {
 114             throw new IllegalArgumentException("Cannot add null value"); //$NON-NLS-1$
 115         }
 116
 117         fLock.writeLock().lock();
 118         try {
 119             fStore.add(val);
 120             // Go backwards to "sift up" like a priority queue
 121             for (int i = size() - 1; i > 0 && COMPARATOR.compare(val, fStore.get(i - 1)) < 0; i--) {
 122                 Collections.swap(fStore, i, i - 1);
 123             }
 124             return true;
 125         } finally {
 126             fLock.writeLock().unlock();
 127         }
 128     }
 129
 130     @Override
 131     public int size() {
 132         return fStore.size();
 133     }
 134
 135     @Override
 136     public boolean isEmpty() {
 137         return fStore.isEmpty();
 138     }
 139
 140     @Override
 141     public boolean contains(@Nullable Object o) {
 142         fLock.readLock().lock();
 143         try {
 144             return fStore.contains(o);
 145         } finally {
 146             fLock.readLock().unlock();
 147         }
 148     }
 149
 150     @Override
 151     public boolean containsAll(@Nullable Collection<?> c) {
 152         fLock.readLock().lock();
 153         try {
 154             return fStore.containsAll(c);
 155         } finally {
 156             fLock.readLock().unlock();
 157         }
 158     }
 159
 160     @Override
 161     public Object[] toArray() {
 162         fLock.readLock().lock();
 163         try {
 164             return fStore.toArray();
 165         } finally {
 166             fLock.readLock().unlock();
 167         }
 168     }
 169
 170     @Override
 171     public <T> T[] toArray(T[] a) {
 172         fLock.readLock().lock();
 173         try {
 174             return fStore.toArray(a);
 175         } finally {
 176             fLock.readLock().unlock();
 177         }
 178     }
 179
 180     @Override
 181     public boolean remove(@Nullable Object o) {
 182         throw new UnsupportedOperationException();
 183     }
 184
 185     @Override
 186     public boolean addAll(@Nullable Collection<? extends E> c) {
 187         if (c == null) {
 188             throw new IllegalArgumentException();
 189         }
 190
 191         fLock.writeLock().lock();
 192         try {
 193             boolean changed = false;
 194             for (E elem : c) {
 195                 if (this.add(elem)) {
 196                     changed = true;
 197                 }
 198             }
 199             return changed;
 200         } finally {
 201             fLock.writeLock().unlock();
 202         }
 203     }
 204
 205     @Override
 206     public boolean removeAll(@Nullable Collection<?> c) {
 207         throw new UnsupportedOperationException();
 208     }
 209
 210     @Override
 211     public boolean retainAll(@Nullable Collection<?> c) {
 212         throw new UnsupportedOperationException();
 213     }
 214
 215     @Override
 216     public void clear() {
 217         fLock.writeLock().lock();
 218         try {
 219             fStore.clear();
 220         } finally {
 221             fLock.writeLock().unlock();
 222         }
 223     }
 224
 225     // ------------------------------------------------------------------------
 226     // Methods added by ISegmentStore
 227     // ------------------------------------------------------------------------
 228
 229     @Override
 230     public Iterable<E> getIntersectingElements(long position) {
 231         /*
 232          * The intervals intersecting 't' are those whose 1) start time is
 233          * *lower* than 't' AND 2) end time is *higher* than 't'.
 234          */
 235         fLock.readLock().lock();
 236         try {
 237             return fStore.stream().filter(element -> position >= element.getStart() && position <= element.getEnd()).collect(Collectors.toList());
 238         } finally {
 239             fLock.readLock().unlock();
 240         }
 241     }
 242
 243     @Override
 244     public Iterable<E> getIntersectingElements(long start, long end) {
 245         fLock.readLock().lock();
 246         try {
 247             return fStore.stream().filter(element -> !(start > element.getEnd() || end < element.getStart())).collect(Collectors.toList());
 248         } finally {
 249             fLock.readLock().unlock();
 250         }
 251     }
 252
 253     @Override
 254     public void dispose() {
 255         fLock.writeLock().lock();
 256         try {
 257             fStore.clear();
 258         } finally {
 259             fLock.writeLock().unlock();
 260         }
 261     }
 262 }