Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.tinkerpop.gremlin.process.traversal.util; import org.apache.commons.lang.StringUtils; import org.apache.tinkerpop.gremlin.process.traversal.Step; import org.apache.tinkerpop.gremlin.process.traversal.Traversal; import org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent; import org.apache.tinkerpop.gremlin.process.traversal.step.util.ProfileStep; import java.io.Serializable; import java.util.ArrayList; import java.util.Collection; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import java.util.TreeMap; import java.util.concurrent.TimeUnit; /** * @author Bob Briody (http://bobbriody.com) * @author Marko A. Rodriguez (http://markorodriguez.com) */ public final class DefaultTraversalMetrics implements TraversalMetrics, Serializable { /** * toString() specific headers */ private static final String[] HEADERS = { "Step", "Count", "Traversers", "Time (ms)", "% Dur" }; private final Map<String, MutableMetrics> metrics = new HashMap<>(); private final TreeMap<Integer, String> indexToLabelMap = new TreeMap<>(); /* The following are computed values upon the completion of profiling in order to report the results back to the user */ private long totalStepDuration; private Map<String, ImmutableMetrics> computedMetrics; public DefaultTraversalMetrics() { } /** * This is only a convenient constructor needed for GraphSON deserialization. */ public DefaultTraversalMetrics(final long totalStepDurationNs, final List<MutableMetrics> metricsMap) { this.totalStepDuration = totalStepDurationNs; this.computedMetrics = new LinkedHashMap<>(this.metrics.size()); metricsMap.forEach(metric -> this.computedMetrics.put(metric.getId(), metric.getImmutableClone())); } @Override public long getDuration(final TimeUnit unit) { return unit.convert(this.totalStepDuration, MutableMetrics.SOURCE_UNIT); } @Override public Metrics getMetrics(final int index) { // adjust index to account for the injected profile steps return this.computedMetrics.get(this.indexToLabelMap.get(index)); } @Override public Metrics getMetrics(final String id) { return this.computedMetrics.get(id); } @Override public Collection<ImmutableMetrics> getMetrics() { return this.computedMetrics.values(); } @Override public String toString() { // Build a pretty table of metrics data. // Append headers final StringBuilder sb = new StringBuilder("Traversal Metrics\n") .append(String.format("%-50s %21s %11s %15s %8s", HEADERS)); sb.append( "\n============================================================================================================="); appendMetrics(this.computedMetrics.values(), sb, 0); // Append total duration sb.append(String.format("%n%50s %21s %11s %15.3f %8s", ">TOTAL", "-", "-", getDuration(TimeUnit.MICROSECONDS) / 1000.0, "-")); return sb.toString(); } private void appendMetrics(final Collection<? extends Metrics> metrics, final StringBuilder sb, final int indent) { // Append each StepMetric's row. indexToLabelMap values are ordered by index. for (Metrics m : metrics) { String rowName = m.getName(); // Handle indentation for (int ii = 0; ii < indent; ii++) { rowName = " " + rowName; } // Abbreviate if necessary rowName = StringUtils.abbreviate(rowName, 50); // Grab the values final Long itemCount = m.getCount(ELEMENT_COUNT_ID); final Long traverserCount = m.getCount(TRAVERSER_COUNT_ID); Double percentDur = (Double) m.getAnnotation(PERCENT_DURATION_KEY); // Build the row string sb.append(String.format("%n%-50s", rowName)); if (itemCount != null) { sb.append(String.format(" %21d", itemCount)); } else { sb.append(String.format(" %21s", "")); } if (traverserCount != null) { sb.append(String.format(" %11d", traverserCount)); } else { sb.append(String.format(" %11s", "")); } sb.append(String.format(" %15.3f", m.getDuration(TimeUnit.MICROSECONDS) / 1000.0)); if (percentDur != null) { sb.append(String.format(" %8.2f", percentDur)); } appendMetrics(m.getNested(), sb, indent + 1); } } private void computeTotals() { // Create temp list of ordered metrics final List<MutableMetrics> tempMetrics = new ArrayList<>(this.metrics.size()); for (final String label : this.indexToLabelMap.values()) { // The indexToLabelMap is sorted by index (key) tempMetrics.add(this.metrics.get(label).clone()); } // Calculate total duration this.totalStepDuration = 0; tempMetrics.forEach(metric -> this.totalStepDuration += metric.getDuration(MutableMetrics.SOURCE_UNIT)); // Assign %'s tempMetrics.forEach(m -> { final double dur = m.getDuration(TimeUnit.NANOSECONDS) * 100.d / this.totalStepDuration; m.setAnnotation(PERCENT_DURATION_KEY, dur); }); // Store immutable instances of the calculated metrics this.computedMetrics = new LinkedHashMap<>(this.metrics.size()); tempMetrics.forEach(it -> this.computedMetrics.put(it.getId(), it.getImmutableClone())); } public static DefaultTraversalMetrics merge(final Iterator<DefaultTraversalMetrics> toMerge) { final DefaultTraversalMetrics newTraversalMetrics = new DefaultTraversalMetrics(); // iterate the incoming TraversalMetrics toMerge.forEachRemaining(inTraversalMetrics -> { // aggregate the internal Metrics inTraversalMetrics.metrics.forEach((metricsId, toAggregate) -> { MutableMetrics aggregateMetrics = newTraversalMetrics.metrics.get(metricsId); if (null == aggregateMetrics) { // need to create a Metrics to aggregate into aggregateMetrics = new MutableMetrics(toAggregate.getId(), toAggregate.getName()); newTraversalMetrics.metrics.put(metricsId, aggregateMetrics); // Set the index of the Metrics for (final Map.Entry<Integer, String> entry : inTraversalMetrics.indexToLabelMap.entrySet()) { if (metricsId.equals(entry.getValue())) { newTraversalMetrics.indexToLabelMap.put(entry.getKey(), metricsId); break; } } } aggregateMetrics.aggregate(toAggregate); }); }); return newTraversalMetrics; } public void setMetrics(final Traversal.Admin traversal, final boolean onGraphComputer) { addTopLevelMetrics(traversal, onGraphComputer); handleNestedTraversals(traversal, null, onGraphComputer); computeTotals(); } private void addTopLevelMetrics(Traversal.Admin traversal, final boolean onGraphComputer) { final List<ProfileStep> profileSteps = TraversalHelper.getStepsOfClass(ProfileStep.class, traversal); for (int ii = 0; ii < profileSteps.size(); ii++) { // The index is necessary to ensure that step order is preserved after a merge. final ProfileStep step = profileSteps.get(ii); if (onGraphComputer) { final MutableMetrics stepMetrics = traversal.getSideEffects().get(step.getId()); this.indexToLabelMap.put(ii, stepMetrics.getId()); this.metrics.put(stepMetrics.getId(), stepMetrics); } else { final MutableMetrics stepMetrics = step.getMetrics(); this.indexToLabelMap.put(ii, stepMetrics.getId()); this.metrics.put(stepMetrics.getId(), stepMetrics); } } } private void handleNestedTraversals(final Traversal.Admin traversal, final MutableMetrics parentMetrics, final boolean onGraphComputer) { long prevDur = 0; for (int i = 0; i < traversal.getSteps().size(); i++) { final Step step = (Step) traversal.getSteps().get(i); if (!(step instanceof ProfileStep)) continue; final MutableMetrics metrics = onGraphComputer ? traversal.getSideEffects().get(step.getId()) : ((ProfileStep) step).getMetrics(); if (null != metrics) { // this happens when a particular branch never received a .next() call (the metrics were never initialized) if (!onGraphComputer) { // subtract upstream duration. long durBeforeAdjustment = metrics.getDuration(TimeUnit.NANOSECONDS); // adjust duration metrics.setDuration(metrics.getDuration(TimeUnit.NANOSECONDS) - prevDur, TimeUnit.NANOSECONDS); prevDur = durBeforeAdjustment; } if (parentMetrics != null) { parentMetrics.addNested(metrics); } if (step.getPreviousStep() instanceof TraversalParent) { for (Traversal.Admin<?, ?> t : ((TraversalParent) step.getPreviousStep()).getLocalChildren()) { handleNestedTraversals(t, metrics, onGraphComputer); } for (Traversal.Admin<?, ?> t : ((TraversalParent) step.getPreviousStep()).getGlobalChildren()) { handleNestedTraversals(t, metrics, onGraphComputer); } } } } } }