Java Code Examples for java.util.Collections.binarySearch()

private int findItemIndex(ArrayList<String> items, int item) {
    //折半查找有序元素的索引
    int index = Collections.binarySearch(items, item, new Comparator<Object>() {
        @Override
        public int compare(Object lhs, Object rhs) {
            String lhsStr = lhs.toString();
            String rhsStr = rhs.toString();
            lhsStr = lhsStr.startsWith("0") ? lhsStr.substring(1) : lhsStr;
            rhsStr = rhsStr.startsWith("0") ? rhsStr.substring(1) : rhsStr;
            return Integer.parseInt(lhsStr) - Integer.parseInt(rhsStr);
        }
    });
    if (index < 0) {
        index = 0;
    }
    return index;
}
 

private void keepFoldState(Fold newFold, List<Fold> oldFolds) {
	int previousLoc = Collections.binarySearch(oldFolds, newFold);
	//System.out.println(newFold + " => " + previousLoc);
	if (previousLoc>=0) {
		Fold prevFold = oldFolds.get(previousLoc);
		newFold.setCollapsed(prevFold.isCollapsed());
	}
	else {
		//previousLoc = -(insertion point) - 1;
		int insertionPoint = -(previousLoc + 1);
		if (insertionPoint>0) {
			Fold possibleParentFold = oldFolds.get(insertionPoint-1);
			if (possibleParentFold.containsOffset(
					newFold.getStartOffset())) {
				List<Fold> children = possibleParentFold.getChildren();
				if (children!=null) {
					keepFoldState(newFold, children);
				}
			}
		}
	}
}
 

@Override
public boolean isValidEndPoint(final URL url) {
    Assert.notNull(this.httpClient);

    HttpEntity entity = null;

    try (CloseableHttpResponse response = this.httpClient.execute(new HttpGet(url.toURI()))) {
        final int responseCode = response.getStatusLine().getStatusCode();

        final int idx = Collections.binarySearch(this.acceptableCodes, responseCode);
        if (idx >= 0) {
            LOGGER.debug("Response code from server matched [{}].", responseCode);
            return true;
        }

        LOGGER.debug("Response code did not match any of the acceptable response codes. Code returned was [{}]", responseCode);

        if (responseCode == HttpStatus.SC_INTERNAL_SERVER_ERROR) {
            final String value = response.getStatusLine().getReasonPhrase();
            LOGGER.error("There was an error contacting the endpoint: [{}]; The error was:\n[{}]", url.toExternalForm(), value);
        }

        entity = response.getEntity();
    } catch (final Exception e) {
        LOGGER.error(e.getMessage(), e);
    } finally {
        EntityUtils.consumeQuietly(entity);
    }
    return false;
}
 

private synchronized int findPositionGE(int offset) {
    while (true) {
        try {
            int index = Collections.binarySearch(knownPositions, offset, new PositionComparator());

            if (index >= 0) {
                return index;
            } else {
                return - (index + 1);
            }
        } catch (Abort a) {
            LOG.log(Level.FINE, "a null Position detected - clearing"); //NOI18N
            int removedCount = 0;
            for (Iterator<Reference<Position>> it = knownPositions.iterator(); it.hasNext(); ) {
                if (it.next().get() == null) {
                    removedCount++;
                    it.remove();
                }
            }
            LOG.log(Level.FINE, "clearing finished, {0} positions cleared", removedCount); //NOI18N
        }
    }
}
 

public static <T> Integer idOfPreviousOrEqual(final List<? extends Comparable<? super T>> list, final T key) {
    if (list == null || list.isEmpty()) {
        return null;
    }
    if (list.get(list.size() - 1).compareTo(key) <= 0) {
        return list.size() - 1;
    }
    int idx = Collections.binarySearch(list, key);
    if (idx < 0) {
        idx = -(idx) - 1;
        if (idx != 0 && idx < list.size()) {
            return idx - 1;
        }
        return null;
    }
    return idx;
}
 

/**
 *
 */
public int add(Object o)
{
    int index = Collections.binarySearch(elements, o, getComparator());
    if (index < 0)
        index = -index - 1;

    elements.add(index, o);
    fireIntervalAdded(this, index, index);

    return index;
}
 

final int[] changedBetweenSnapshots(Snapshot from, Snapshot to) {
  Snapshot earlier = from;
  Snapshot later = to;
  if (Snapshot.ID_COMPARATOR.compare(from, to) > 0) {
    earlier = to;
    later = from;
  }

  final int size = diffs.size();
  int earlierDiffIndex = Collections.binarySearch(diffs, earlier.getId());
  int laterDiffIndex = later == null ? size : Collections
      .binarySearch(diffs, later.getId());
  if (-earlierDiffIndex - 1 == size) {
    // if the earlierSnapshot is after the latest SnapshotDiff stored in
    // diffs, no modification happened after the earlierSnapshot
    return null;
  }
  if (laterDiffIndex == -1 || laterDiffIndex == 0) {
    // if the laterSnapshot is the earliest SnapshotDiff stored in diffs, or
    // before it, no modification happened before the laterSnapshot
    return null;
  }
  earlierDiffIndex = earlierDiffIndex < 0 ? (-earlierDiffIndex - 1)
      : earlierDiffIndex;
  laterDiffIndex = laterDiffIndex < 0 ? (-laterDiffIndex - 1)
      : laterDiffIndex;
  return new int[]{earlierDiffIndex, laterDiffIndex};
}
 

/**
 * Returns true if the span defined by the half-open
 * interval from <code>start</code> up to,
 * but not including, <code>end</code> intersects
 * any of the spans defined by this instance.
 */
public boolean intersects(float start, float end) {
    boolean doesIntersect;

    if (mSpans != null) {

        /* If we have added any spans since we last
         * sorted and collapsed our list of spans
         * then we need to resort and collapse.
         */
        if (mAddsSinceSort > 0) {
            sortAndCollapse();
        }

        /* The SpanIntersection comparator considers
         * two spans equal if they intersect. If
         * the search finds a match then we have an
         * intersection.
         */
        int found = Collections.binarySearch(mSpans,
                                             new Span(start, end),
                                             SpanIntersection.instance);

        doesIntersect = found >= 0;

    /* The addInfinite() method has been invoked so
     * everything intersect this instance.
     */
    } else {
       doesIntersect = true;
    }

    return doesIntersect;
}
 

/**
 * Returns a buffer to the pool, throwing away old buffers if the pool would exceed its allotted
 * size.
 *
 * @param buf the buffer to return to the pool.
 */
public synchronized void returnBuf(byte[] buf) {
    if (buf == null || buf.length > mSizeLimit) {
        return;
    }
    mBuffersByLastUse.add(buf);
    int pos = Collections.binarySearch(mBuffersBySize, buf, BUF_COMPARATOR);
    if (pos < 0) {
        pos = -pos - 1;
    }
    mBuffersBySize.add(pos, buf);
    mCurrentSize += buf.length;
    trim();
}
 

public int deleteSplitOrphans() {
  final List<SplitRange> ranges = new ArrayList<>();

  int itemsDeleted = 0;
  for(Map.Entry<byte[], NameSpaceContainer> entry : namespace.find()) {
    NameSpaceContainer container = entry.getValue();
    if(container.getType() == Type.DATASET && container.getDataset().getReadDefinition() != null && container.getDataset().getReadDefinition().getSplitVersion() != null) {
      ranges.add(new SplitRange(DatasetSplitId.getSplitStringRange(container.getDataset())));
    }
  }

  for(Map.Entry<DatasetSplitId, DatasetSplit> e : splitsStore.find()) {
    String id = e.getKey().getSplitIdentifier();
    final int item = Collections.binarySearch(ranges, new SplitRange(Range.singleton(id)));

    // we should never find a match since we're searching for a split key.
    Preconditions.checkArgument(item < 0);

    final int insertionPoint = (-item) - 1;
    final int consideredRange = insertionPoint - 1; // since a normal match would come directly after the start range, we need to check the range directly above the insertion point.

    if(consideredRange < 0 || ranges.get(consideredRange).range.contains(id)) {
      splitsStore.delete(e.getKey());
      itemsDeleted++;
    }
  }
  return itemsDeleted;
}
 

/**
 * Returns a buffer to the pool, throwing away old buffers if the pool would exceed its allotted
 * size.
 *
 * @param buf the buffer to return to the pool.
 */
public synchronized void returnBuf(byte[] buf) {
    if (buf == null || buf.length > mSizeLimit) {
        return;
    }
    mBuffersByLastUse.add(buf);
    int pos = Collections.binarySearch(mBuffersBySize, buf, BUF_COMPARATOR);
    if (pos < 0) {
        pos = -pos - 1;
    }
    mBuffersBySize.add(pos, buf);
    mCurrentSize += buf.length;
    trim();
}
 

private int findPositionIndex(List<Position> positions, final int target) {
    return Collections.binarySearch(positions, new Position() {
        public int getOffset() {
            return target;
        }
    }, new Comparator<Position>() {
        public int compare(Position pos1, Position pos2) {
            return pos1.getOffset() - pos2.getOffset();
        }
    });
}
 

public int findStringIndex(String s) {
    return Collections.binarySearch(strings, s);
}
 

/**
 * Spread backups of failed superpeer
 *
 * @param p_lastBackupSuperpeer
 *         the last backup superpeer
 * @lock overlay lock must be read-locked
 */
private void spreadBackupsOfThisSuperpeer(final short p_lastBackupSuperpeer) {
    short newBackupSuperpeer;
    int index;
    boolean superpeerToSendData = false;
    byte[] metadata;
    String str = "Spreaded data of ";

    metadata = m_metadata.receiveMetadataInRange(m_predecessor, m_nodeID);

    while (!m_superpeers.isEmpty()) {
        // Determine successor of last backup superpeer
        index = (short) Collections.binarySearch(m_superpeers, (short) (p_lastBackupSuperpeer + 1));
        if (index < 0) {
            index = index * -1 - 1;
            if (index == m_superpeers.size()) {
                index = 0;
            }
        }
        newBackupSuperpeer = m_superpeers.get(index);

        superpeerToSendData = true;
        str += " to " + NodeID.toHexString(newBackupSuperpeer);

        try {
            m_network.sendMessage(new SendBackupsMessage(newBackupSuperpeer, metadata));
        } catch (final NetworkException e) {
            // Superpeer is not available anymore, remove from superpeer array and try next superpeer
            // #if LOGGER >= ERROR
            LOGGER.error("new backup superpeer (0x%X) failed, too", newBackupSuperpeer);
            // #endif /* LOGGER >= ERROR */
            continue;
        }
        break;
    }
    // #if LOGGER >= DEBUG
    if (metadata.length > 0 && superpeerToSendData) {
        LOGGER.debug(str);
    } else {
        LOGGER.debug("No need to spread data");
    }
    // #endif /* LOGGER >= DEBUG */
}
 

public int findTypeIndex(String descriptor) {
    return Collections.binarySearch(typeNames, descriptor);
}
 

/**
 * Determines the responsible superpeer for given NodeID
 *
 * @param p_nodeID
 *         NodeID from chunk whose location is searched
 * @param p_check
 *         whether the result has to be checked (in case of incomplete superpeer overlay) or not
 * @return the responsible superpeer for given ChunkID
 * @lock overlay lock must be read-locked
 */
private short getResponsibleSuperpeer(final short p_nodeID, final boolean p_check) {
    short responsibleSuperpeer = NodeID.INVALID_ID;
    short predecessor;
    short hisSuccessor;
    int index;
    AskAboutSuccessorRequest request;
    AskAboutSuccessorResponse response;

    // #if LOGGER == TRACE
    LOGGER.trace("Entering getResponsibleSuperpeer with: p_nodeID=0x%X", p_nodeID);
    // #endif /* LOGGER == TRACE */

    if (!m_superpeers.isEmpty()) {
        index = Collections.binarySearch(m_superpeers, p_nodeID);
        if (index < 0) {
            index = index * -1 - 1;
            if (index == m_superpeers.size()) {
                index = 0;
            }
        }
        responsibleSuperpeer = m_superpeers.get(index);

        if (p_check && m_superpeers.size() > 1) {
            if (index == 0) {
                index = m_superpeers.size() - 1;
            } else {
                index--;
            }
            predecessor = m_superpeers.get(index);

            while (true) {
                m_overlayLock.readLock().unlock();
                request = new AskAboutSuccessorRequest(predecessor);
                try {
                    m_network.sendSync(request);
                } catch (final NetworkException e) {
                    // Predecessor is not available, try responsibleSuperpeer without checking
                    m_overlayLock.readLock().lock();
                    break;
                }

                m_overlayLock.readLock().lock();

                response = request.getResponse(AskAboutSuccessorResponse.class);
                hisSuccessor = response.getSuccessor();
                if (responsibleSuperpeer == hisSuccessor) {
                    break;
                } else if (OverlayHelper.isSuperpeerInRange(p_nodeID, predecessor, hisSuccessor)) {
                    responsibleSuperpeer = hisSuccessor;
                    break;
                } else {
                    predecessor = hisSuccessor;
                }
            }
        }
    } else {
        // #if LOGGER >= WARN
        LOGGER.warn("Do not know any superpeer");
        // #endif /* LOGGER >= WARN */
    }
    // #if LOGGER == TRACE
    LOGGER.trace("Exiting getResponsibleSuperpeer");
    // #endif /* LOGGER == TRACE */

    return responsibleSuperpeer;
}
 

/**
 *
 */
public int indexOf(Object o)
{
    return Collections.binarySearch(elements, o, getComparator());
}
 

@Override
public void insertUpdate(DocumentEvent ev) {
    if (ev.getLength() != 1)
        return;

    int pos = ev.getOffset();
    String content = null;
    try {
        content = textField.getText(0, pos + 1);
    } catch (BadLocationException e) {
        e.printStackTrace();
    }

    // Find where the word starts
    int w;
    for (w = pos; w >= 0; w--) {
        if (!Character.isLetter(content.charAt(w))) {
            break;
        }
    }

    // Too few chars
    if (pos - w < 2)
        return;

    String prefix = content.substring(w + 1).toLowerCase();
    int n = Collections.binarySearch(keywords, prefix);
    if (n < 0 && -n <= keywords.size()) {
        String match = keywords.get(-n - 1);
        if (match.startsWith(prefix)) {
            // A completion is found
            String completion = match.substring(pos - w);
            // We cannot modify Document from within notification,
            // so we submit a task that does the change later
            SwingUtilities.invokeLater(new CompletionTask(completion, pos + 1));
        }
    } else {
        // Nothing found
        mode = Mode.INSERT;
    }
}
 

/**
 * {@link Collections#binarySearch(List, Object, Comparator) Searches}
 * {@code sortedList} for {@code key} using the binary search algorithm. The
 * list must be sorted using this ordering.
 *
 * @param sortedList the list to be searched
 * @param key the key to be searched for
 * @deprecated Use {@link Collections#binarySearch(List, Object, Comparator)} directly. This
 * method is scheduled for deletion in June 2018.
 */
@Deprecated
public int binarySearch(List<? extends T> sortedList, @Nullable T key) {
  return Collections.binarySearch(sortedList, key, this);
}
 

/**
 * {@link Collections#binarySearch(List, Object, Comparator) Searches}
 * {@code sortedList} for {@code key} using the binary search algorithm. The
 * list must be sorted using this ordering.
 *
 * @param sortedList the list to be searched
 * @param key the key to be searched for
 */
public int binarySearch(List<? extends T> sortedList, @Nullable T key) {
  return Collections.binarySearch(sortedList, key, this);
}