Java tutorial
/* COPYRIGHT STATUS: Dec 1st 2001, Fermi National Accelerator Laboratory (FNAL) documents and software are sponsored by the U.S. Department of Energy under Contract No. DE-AC02-76CH03000. Therefore, the U.S. Government retains a world-wide non-exclusive, royalty-free license to publish or reproduce these documents and software for U.S. Government purposes. All documents and software available from this server are protected under the U.S. and Foreign Copyright Laws, and FNAL reserves all rights. Distribution of the software available from this server is free of charge subject to the user following the terms of the Fermitools Software Legal Information. Redistribution and/or modification of the software shall be accompanied by the Fermitools Software Legal Information (including the copyright notice). The user is asked to feed back problems, benefits, and/or suggestions about the software to the Fermilab Software Providers. 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Anyone downloading information from this server is obligated to secure any necessary Government licenses before exporting documents or software obtained from this server. */ package org.dcache.util.histograms; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.ObjectMapper; import org.apache.commons.math3.util.FastMath; import org.junit.After; import org.junit.Test; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.util.ArrayList; import java.util.Calendar; import java.util.List; import java.util.Random; import java.util.concurrent.TimeUnit; import org.dcache.util.histograms.HistogramModel.UpdateOperation; import org.dcache.util.histograms.TimeFrame.BinType; import org.dcache.util.histograms.TimeFrame.Type; import static junit.framework.TestCase.assertEquals; import static junit.framework.TestCase.assertNotNull; import static junit.framework.TestCase.assertNull; import static org.junit.Assert.assertTrue; public class HistogramModelTest { private static final Logger LOGGER = LoggerFactory.getLogger(HistogramModelTest.class); private static final Random RANDOM = new Random(System.currentTimeMillis()); private HistogramModel model; private HistogramModel originalModel; private Exception error; private String serialized1; private String serialized2; @Test public void binUnitShouldBe1ForMaxValue50Days() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(50); givenBinCountOf(51); givenBinUnitOf((double) TimeUnit.DAYS.toMillis(1)); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildSucceeded(); assertThatBinWidthIs(1); } @Test public void binUnitShouldBe2ForMaxValue100Days() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(100); givenBinCountOf(51); givenBinUnitOf((double) TimeUnit.DAYS.toMillis(1)); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildSucceeded(); assertThatBinWidthIs(2); } @Test public void binUnitShouldBe3ForMaxValue101Days() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(101); givenBinCountOf(51); givenBinUnitOf((double) TimeUnit.DAYS.toMillis(1)); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildSucceeded(); assertThatBinWidthIs(3); } @Test public void buildShouldFailWhenNoCountGivenToCounting() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(150); givenBinUnitOf((double) TimeUnit.DAYS.toMillis(1)); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildFailed(); } @Test public void buildShouldFailWhenNoDataGivenToCountingHistogram() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); whenConfigureIsCalled(); assertThatBuildFailed(); } @Test public void buildShouldFailWhenNoUnitGivenToCountingHistogram() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(150); givenBinCountOf(51); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildFailed(); } @Test public void buildShouldSucceedForTimeframeHistogramWithoutData() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); assertThatBuildSucceeded(); } @Test public void buildShouldSucceedForTimeframeHistogramWithoutFileSizeValues() throws JsonProcessingException, NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenValidTimeframeSpecification(); whenConfigureIsCalled(); assertThatBuildSucceeded(); } @Test public void buildShouldSucceedForTimeframeHistogramWithFileSizeValues() throws JsonProcessingException, NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenFileSizeValuesFor(24); givenValidTimeframeSpecification(); whenConfigureIsCalled(); assertThatBuildSucceeded(); } @After public void printDiagnostics() throws JsonProcessingException { if (model != null) { LOGGER.info(new ObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(model)); LOGGER.info( new ObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(model.toHistogram())); } } @Test public void rebuiltTimeframeHistogramShouldBeTheSameAsOriginal() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); whenHistogramIsStored(); givenTimeframeHistogram(); whenConfigureIsCalled(); assertThatOriginalHistogramEqualsStored(); } @Test public void serializedTimeframeHistogramShouldDeserializeCorrectly() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); whenHistogramIsSerialized(); whenHistogramIsDeserialized(); whenHistogramIsSerializedAgain(); assertThatSerializationsAreEqual(); } @Test public void updateOnTimeframeHistogramShouldAverageLastValue() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); assertThatUpdateAveragesLastValue(); } @Test public void updateOnTimeframeHistogramShouldReplaceLastValue() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); assertThatUpdateReplacesLastValue(); } @Test public void updateOnTimeframeHistogramShouldRotateBuffer() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(3)); whenConfigureIsCalled(); assertThatUpdateRotatesBuffer(3); } @Test public void updateOnTimeframeHistogramShouldRotateBufferToMaximum() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(53)); whenConfigureIsCalled(); assertThatUpdateRotatesBuffer(53); } @Test public void updateOnTimeframeHistogramShouldSumLastValue() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenTimeframeHistogram(); givenQueueCountValuesFor(48); givenBinUnitOf((double) TimeUnit.HOURS.toMillis(1)); givenBinCountOf(48); givenBinLabelOf(TimeUnit.HOURS.name()); givenDataLabelOf("COUNT"); givenHistogramTypeOf("Queued Movers"); givenHighestBinOf(getHoursInThePastFromNow(0)); whenConfigureIsCalled(); assertThatUpdateSumsLastValue(); } @Test public void updateShouldFailOnCountingHistogram() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException { givenCountingHistogram(); givenFilelifetimeValuesFor(150); givenBinCountOf(51); givenBinUnitOf((double) TimeUnit.DAYS.toMillis(1)); givenBinLabelOf(TimeUnit.DAYS.name()); givenDataLabelOf("Count"); givenDataLabelOf("COUNT"); givenHistogramTypeOf("File Lifetime Count"); whenConfigureIsCalled(); assertThatBuildSucceeded(); assertThatUpdateFails(); } private void assertThatBinWidthIs(int numUnits) { assertEquals("wrong binWidth", numUnits, (int) model.binWidth); } private void assertThatBuildFailed() { assertNotNull("Build succeeded but should have failed", error); model = null; } private void assertThatBuildSucceeded() { String msg = error == null ? null : error.getMessage(); assertNull(msg, error); } private void assertThatOriginalHistogramEqualsStored() { try { assertTrue(model.getClass().equals(originalModel.getClass())); String original = new ObjectMapper().writeValueAsString(originalModel); String restored = new ObjectMapper().writeValueAsString(model); assertEquals("object strings are not the same", original, restored); } catch (JsonProcessingException e) { assertNull(e.getMessage(), e); } } private void assertThatSerializationsAreEqual() { assertEquals("serializations are not equal", serialized1, serialized2); } private void assertThatUpdateAveragesLastValue() { Double[][] values = values(); Double[] last = values[values.length - 1]; double lastValue = last[1]; double newValue = lastValue * 3; double average = (lastValue + newValue) / 2; model.update(newValue, UpdateOperation.AVERAGE, System.currentTimeMillis()); values = values(); assertTrue("value was not replaced", lastValue != values[values.length - 1][1]); assertTrue("last value was replaced with faulty value", average == values[values.length - 1][1]); } private void assertThatUpdateFails() { Exception thrown = null; try { model.update(1.243, UpdateOperation.REPLACE, System.currentTimeMillis()); } catch (UnsupportedOperationException e) { thrown = e; } assertNotNull(thrown); assertTrue(thrown instanceof UnsupportedOperationException); } private void assertThatUpdateReplacesLastValue() { Double[][] values = values(); Double[] last = values[values.length - 1]; double lastValue = last[1]; double newValue = lastValue * 3; model.update(newValue, UpdateOperation.REPLACE, System.currentTimeMillis()); values = values(); assertTrue("value was not replaced", lastValue != values[values.length - 1][1]); assertTrue("last value was replaced with faulty value", newValue == values[values.length - 1][1]); } private void assertThatUpdateRotatesBuffer(int units) { Double[][] originals = values(); long now = System.currentTimeMillis(); model.update(2.53, UpdateOperation.AVERAGE, now); model.update(5.71, UpdateOperation.AVERAGE, now); Double[][] rotated = values(); assertTrue("new buffer has wrong size", originals.length == rotated.length); int r = 0; for (int i = units; i < originals.length; ++i) { assertTrue("rotated value " + r + " is incorrect", originals[i][1] == rotated[r][1]); ++r; } for (; r < rotated.length - 1; ++r) { assertTrue("rotated value " + r + " is incorrect", null == rotated[r][1]); } assertTrue("last rotated value is incorrect", rotated[rotated.length - 1][1] == 4.12); HistogramMetadata metadata = model.metadata; int[] counts = metadata.getBinCounts(); assertTrue("last rotated count is incorrect", counts[metadata.rotatedIndex(rotated.length - 1)] == 2); } private void assertThatUpdateSumsLastValue() { Double[][] values = values(); Double[] last = values[values.length - 1]; double lastValue = last[1]; double newValue = lastValue * 3; model.update(newValue, UpdateOperation.SUM, System.currentTimeMillis()); values = values(); assertTrue("value was not replaced", lastValue != values[values.length - 1][1]); assertTrue("last value was replaced with faulty value", newValue + lastValue == values[values.length - 1][1]); } private double getHoursInThePastFromNow(int hours) { Calendar calendar = Calendar.getInstance(); long diff = TimeUnit.HOURS.toMillis(hours); calendar.setTimeInMillis(System.currentTimeMillis() - diff); calendar.set(Calendar.MINUTE, 0); calendar.set(Calendar.SECOND, 0); calendar.set(Calendar.MILLISECOND, 0); return (double) calendar.getTimeInMillis(); } private List<Double> getQueueCountsFor(int units) { List<Double> queue = new ArrayList<>(); int radix = 1000; for (int i = 0; i < units; ++i) { long count = FastMath.abs(RANDOM.nextLong()) % radix; queue.add((double) count); } return queue; } private List<Double> getRawBytesFor(int units) { List<Double> bytes = new ArrayList<>(); int radix = 1024; for (int i = 0; i < units; ++i) { long size = FastMath.abs(RANDOM.nextLong()) % radix; size *= 1024 * 1024 * 1024; bytes.add((double) size); } return bytes; } private List<Double> getRawLifetimes(int days) { List<Double> lifetimes = new ArrayList<>(); long radix = TimeUnit.DAYS.toMillis(days); /* * Ensure that the max is there so * the assertion always works, regardless * of the other random values. */ lifetimes.add((double) radix); for (int i = 1; i < days; ++i) { long duration = FastMath.abs(RANDOM.nextLong()) % radix; lifetimes.add((double) duration); } return lifetimes; } private void givenBinCountOf(int count) { model.setBinCount(count); } private void givenBinLabelOf(String binType) { model.setBinUnitLabel(binType); } private void givenBinUnitOf(double unit) { model.setBinUnit(unit); } private void givenTimeframeHistogram() throws InvocationTargetException, NoSuchMethodException, InstantiationException, IllegalAccessException { withHistogramModel(TimeseriesHistogram.class); } private void givenCountingHistogram() throws InvocationTargetException, NoSuchMethodException, InstantiationException, IllegalAccessException { withHistogramModel(CountingHistogram.class); } private void givenDataLabelOf(String label) { model.setDataUnitLabel(label); } private void givenFileSizeValuesFor(int units) { model.setData(getRawBytesFor(units)); } private void givenFilelifetimeValuesFor(int units) { model.setData(getRawLifetimes(units)); } private void givenHighestBinOf(double bin) { model.setHighestBin(bin); } private void givenHistogramTypeOf(String type) { model.setIdentifier(type); } private void givenQueueCountValuesFor(int units) { model.setData(getQueueCountsFor(units)); } private void givenValidTimeframeSpecification() { Calendar high = TimeFrame.computeHighTimeFromNow(BinType.HOUR); TimeFrame timeFrame = new TimeFrame(high.getTimeInMillis()); timeFrame.setTimebin(BinType.HOUR); timeFrame.setTimeframe(Type.DAY); ((TimeseriesHistogram) model).withTimeFrame(timeFrame); model.setDataUnitLabel("BYTES"); } private Double[][] values() { Histogram h = model.toHistogram(); return h.getValues(); } private void whenConfigureIsCalled() { try { model.setIdentifier("test-histogram"); model.configure(); } catch (Exception e) { error = e; } } private void whenHistogramIsDeserialized() { try { model = new ObjectMapper().readValue(serialized1, model.getClass()); } catch (IOException e) { assertNull(e.toString(), e); } } private void whenHistogramIsSerialized() { try { serialized1 = new ObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(model); } catch (JsonProcessingException e) { assertNull(e.toString(), e); } } private void whenHistogramIsSerializedAgain() { try { serialized2 = new ObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(model); } catch (JsonProcessingException e) { assertNull(e.toString(), e); } } private void whenHistogramIsStored() throws InvocationTargetException, NoSuchMethodException, InstantiationException, IllegalAccessException { originalModel = model; withHistogramModel(model.getClass()); } private <T extends HistogramModel> void withHistogramModel(Class<T> clzz) throws IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException { if (model == null) { model = clzz.newInstance(); } else { model = clzz.getConstructor(clzz).newInstance(clzz.cast(model)); } } }