java.util.TreeMap#lowerEntry ( )源码实例Demo

/**
 * lowerEntry returns preceding entry.
 */
public void testLowerEntry() {
    TreeMap map = map5();
    Map.Entry e1 = map.lowerEntry(three);
    assertEquals(two, e1.getKey());

    Map.Entry e2 = map.lowerEntry(six);
    assertEquals(five, e2.getKey());

    Map.Entry e3 = map.lowerEntry(one);
    assertNull(e3);

    Map.Entry e4 = map.lowerEntry(zero);
    assertNull(e4);
}
 

/**
 * lowerEntry returns preceding entry.
 */
public void testLowerEntry() {
    TreeMap map = map5();
    Map.Entry e1 = map.lowerEntry(three);
    assertEquals(two, e1.getKey());

    Map.Entry e2 = map.lowerEntry(six);
    assertEquals(five, e2.getKey());

    Map.Entry e3 = map.lowerEntry(one);
    assertNull(e3);

    Map.Entry e4 = map.lowerEntry(zero);
    assertNull(e4);
}
 

public boolean containsNearbyAlmostDuplicate(int[] nums, int k, int t) {
    if (nums.length == 0 || k == 0) {
        return false;
    }
    TreeMap<Integer, Integer> map = new TreeMap<>();
    for (int i = 0; i < nums.length; i++) {
        int lowerEntry = nums[i] - t - 1;
        int higherEntry = nums[i] + t + 1;
        Map.Entry<Integer, Integer> higher = map.lowerEntry(higherEntry);
        if (higher != null && higher.getKey() >= nums[i]) {
            return true;
        }
        Map.Entry<Integer, Integer> lower = map.higherEntry(lowerEntry);
        if (lower != null && lower.getKey() <= nums[i]) {
            return true;
        }
        if (map.size() == k) {
            map.compute(nums[i - k], (key, val) -> {
                if (val == 1) {
                    return null;
                } else {
                    return val - 1;
                }
            });
        }
        map.compute(nums[i], (key, val) -> {
            if (val == null) {
                return 1;
            } else {
                return val + 1;
            }
        });
    }
    return false;
}
 

/**
 * Precondition:
 * 1. Index are rotated with name pattern ".opendistro-anomaly-results-history-{now/d}-1" and now is using UTC.
 * 2. Latest entry with error is recorded within enabled and disabled time.  Note disabled time can be null.
 *
 * Error is populated if error of the latest anomaly result is not empty.
 *
 * Two optimization to avoid scanning all anomaly result indices to get a detector's most recent error
 *
 * First, when a detector is running, we only need to scan the current index, not all of the rolled over ones
 *  since we are interested in the latest error.
 * Second, when a detector is disabled, we only need to scan the latest anomaly result indices created before the
 *  detector's enable time.
 *
 * @param detectorId detector id
 * @param enabledTimeMillis the time when AD job is enabled in milliseconds
 * @param listener listener to process the returned error or exception
 */
private void profileError(
    String detectorId,
    long enabledTimeMillis,
    Instant disabledTime,
    MultiResponsesDelegateActionListener<DetectorProfile> listener
) {
    String[] latestIndex = null;

    long disabledTimeMillis = 0;
    if (disabledTime != null) {
        disabledTimeMillis = disabledTime.toEpochMilli();
    }
    if (enabledTimeMillis > disabledTimeMillis) {
        // detector is still running
        latestIndex = new String[1];
        latestIndex[0] = AnomalyResult.ANOMALY_RESULT_INDEX;
    } else {
        String[] concreteIndices = indexNameExpressionResolver
            .concreteIndexNames(
                clusterService.state(),
                IndicesOptions.lenientExpandOpen(),
                AnomalyDetectionIndices.ALL_AD_RESULTS_INDEX_PATTERN
            );

        // find the latest from result indices such as .opendistro-anomaly-results-history-2020.04.06-1 and
        // /.opendistro-anomaly-results-history-2020.04.07-000002
        long maxTimestamp = -1;
        TreeMap<Long, List<String>> candidateIndices = new TreeMap<>();
        for (String indexName : concreteIndices) {
            Matcher m = Pattern.compile("\\.opendistro-anomaly-results-history-(\\d{4})\\.(\\d{2})\\.(\\d{2})-\\d+").matcher(indexName);
            if (m.matches()) {
                int year = Integer.parseInt(m.group(1));
                int month = Integer.parseInt(m.group(2));
                int date = Integer.parseInt(m.group(3));
                // month starts with 0
                calendar.clear();
                calendar.set(year, month - 1, date);
                // 2020.05.08 is translated to 1588896000000
                long timestamp = calendar.getTimeInMillis();

                // a candidate index can be created before or after enabled time, but the index is definitely created before disabled
                // time
                if (timestamp <= disabledTimeMillis && maxTimestamp <= timestamp) {
                    maxTimestamp = timestamp;
                    // we can have two rotations on the same day and we don't know which one has our data, so we keep all
                    List<String> indexList = candidateIndices.computeIfAbsent(timestamp, k -> new ArrayList<String>());
                    indexList.add(indexName);
                }
            }
        }
        List<String> candidates = new ArrayList<String>();
        List<String> latestCandidate = candidateIndices.get(maxTimestamp);

        if (latestCandidate != null) {
            candidates.addAll(latestCandidate);
        }

        // look back one more index for an edge case:
        // Suppose detector interval is 1 minute. Detector last run is at 2020-05-07, 11:59:50 PM,
        // then AD result indices rolled over as .opendistro-anomaly-results-history-2020.05.07-001
        // Detector next run will be 2020-05-08, 00:00:50 AM. If a user stop the detector at
        // 2020-05-08 00:00:10 AM, detector will not have AD result on 2020-05-08.
        // We check AD result indices one day earlier to make sure we can always get AD result.
        Map.Entry<Long, List<String>> earlierCandidate = candidateIndices.lowerEntry(maxTimestamp);
        if (earlierCandidate != null) {
            candidates.addAll(earlierCandidate.getValue());
        }
        latestIndex = candidates.toArray(new String[0]);
    }

    if (latestIndex == null || latestIndex.length == 0) {
        // no result index found: can be due to anomaly result is not created yet or result indices for the detector have been deleted.
        listener.onResponse(new DetectorProfile());
        return;
    }
    SearchRequest searchLatestResult = createLatestAnomalyResultRequest(detectorId, enabledTimeMillis, disabledTimeMillis, latestIndex);
    client.search(searchLatestResult, onGetLatestAnomalyResult(listener, detectorId));
}
 

public void getLowestEntry(TreeMap<String, String> maps, String key) {
    Map.Entry<String,String> entry = maps.lowerEntry(key);
    System.out.println("前一个的Entry如下");
    System.out.print("key = " + entry.getKey());
    System.out.println(" value = " + entry.getValue());
}