Factor out labelValue length check to abstract base class and small name fix

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131902964

java/google/registry/monitoring/metrics/AbstractMetric.java

@@ -14,6 +14,7 @@
 
 package google.registry.monitoring.metrics;
 
+
 import com.google.common.base.MoreObjects;
 import com.google.common.collect.ImmutableSet;
 import google.registry.monitoring.metrics.MetricSchema.Kind;

java/google/registry/monitoring/metrics/Counter.java

@@ -50,10 +50,6 @@ public final class Counter extends AbstractMetric<Long>
   private static final float HASHMAP_LOAD_FACTOR = 0.75f;
   private static final int HASHMAP_CONCURRENCY_LEVEL = 16;
 
-  private static final String LABEL_COUNT_ERROR =
-      "The count of labelValues must be equal to the underlying "
-          + "MetricDescriptor's count of labels.";
-
   /**
    * A map of the {@link Counter} values, with a list of label values as the keys.
    *
@@ -89,13 +85,13 @@ public final class Counter extends AbstractMetric<Long>
   }
 
   @VisibleForTesting
-  void incrementBy(long offset, Instant startTime, ImmutableList<String> labelValues) {
+  void incrementBy(long offset, Instant startTimestamp, ImmutableList<String> labelValues) {
     Lock lock = valueLocks.get(labelValues);
     lock.lock();
 
     try {
       values.addAndGet(labelValues, offset);
-      valueStartTimestamps.putIfAbsent(labelValues, startTime);
+      valueStartTimestamps.putIfAbsent(labelValues, startTimestamp);
     } finally {
       lock.unlock();
     }
@@ -103,7 +99,7 @@ public final class Counter extends AbstractMetric<Long>
 
   @Override
   public final void incrementBy(long offset, String... labelValues) {
-    checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(this, labelValues);
     checkArgument(offset >= 0, "The offset provided must be non-negative");
 
     incrementBy(offset, Instant.now(), ImmutableList.copyOf(labelValues));
@@ -111,7 +107,7 @@ public final class Counter extends AbstractMetric<Long>
 
   @Override
   public final void increment(String... labelValues) {
-    checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(this, labelValues);
 
     incrementBy(1L, Instant.now(), ImmutableList.copyOf(labelValues));
   }
@@ -152,13 +148,13 @@ public final class Counter extends AbstractMetric<Long>
   }
 
   @VisibleForTesting
-  final void set(Long value, Instant startTime, ImmutableList<String> labelValues) {
+  final void set(Long value, Instant startTimestamp, ImmutableList<String> labelValues) {
     Lock lock = valueLocks.get(labelValues);
     lock.lock();
 
     try {
       this.values.put(labelValues, value);
-      valueStartTimestamps.putIfAbsent(labelValues, startTime);
+      valueStartTimestamps.putIfAbsent(labelValues, startTimestamp);
     } finally {
       lock.unlock();
     }
@@ -166,13 +162,13 @@ public final class Counter extends AbstractMetric<Long>
 
   @Override
   public final void set(Long value, String... labelValues) {
-    checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(this, labelValues);
 
     set(value, Instant.now(), ImmutableList.copyOf(labelValues));
   }
 
   @VisibleForTesting
-  final void reset(Instant startTime) {
+  final void reset(Instant startTimestamp) {
     // Lock the entire set of values so that all existing values will have a consistent timestamp
     // after this call, without the possibility of interleaving with another reset() call.
     Set<ImmutableList<String>> keys = values.asMap().keySet();
@@ -182,7 +178,7 @@ public final class Counter extends AbstractMetric<Long>
 
     for (ImmutableList<String> labelValues : keys) {
       this.values.put(labelValues, 0);
-      this.valueStartTimestamps.put(labelValues, startTime);
+      this.valueStartTimestamps.put(labelValues, startTimestamp);
     }
 
     for (int i = 0; i < valueLocks.size(); i++) {
@@ -196,13 +192,13 @@ public final class Counter extends AbstractMetric<Long>
   }
 
   @VisibleForTesting
-  final void reset(Instant startTime, ImmutableList<String> labelValues) {
+  final void reset(Instant startTimestamp, ImmutableList<String> labelValues) {
     Lock lock = valueLocks.get(labelValues);
     lock.lock();
 
     try {
       this.values.put(labelValues, 0);
-      this.valueStartTimestamps.put(labelValues, startTime);
+      this.valueStartTimestamps.put(labelValues, startTimestamp);
     } finally {
       lock.unlock();
     }
@@ -210,7 +206,7 @@ public final class Counter extends AbstractMetric<Long>
 
   @Override
   public final void reset(String... labelValues) {
-    checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(this, labelValues);
 
     reset(Instant.now(), ImmutableList.copyOf(labelValues));
   }

java/google/registry/monitoring/metrics/MetricPoint.java

@@ -14,8 +14,6 @@
 
 package google.registry.monitoring.metrics;
 
-import static com.google.common.base.Preconditions.checkArgument;
-
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
 import org.joda.time.Instant;
@@ -28,12 +26,6 @@ import org.joda.time.Interval;
 @AutoValue
 public abstract class MetricPoint<V> {
 
-  private static final String LABEL_COUNT_ERROR =
-      "The count of labelsValues must be equal to the underlying "
-          + "MetricDescriptor's count of labels.";
-
-  MetricPoint() {}
-
   /**
    * Returns a new {@link MetricPoint} representing a value at a specific {@link Instant}.
    *
@@ -42,8 +34,8 @@ public abstract class MetricPoint<V> {
    */
   static <V> MetricPoint<V> create(
       Metric<V> metric, ImmutableList<String> labelValues, Instant timestamp, V value) {
-    checkArgument(
-        labelValues.size() == metric.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(metric, labelValues);
+
     return new AutoValue_MetricPoint<>(
         metric, labelValues, new Interval(timestamp, timestamp), value);
   }
@@ -61,8 +53,8 @@ public abstract class MetricPoint<V> {
       Instant startTime,
       Instant endTime,
       V value) {
-    checkArgument(
-        labelValues.size() == metric.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(metric, labelValues);
+
     return new AutoValue_MetricPoint<>(
         metric, labelValues, new Interval(startTime, endTime), value);
   }

java/google/registry/monitoring/metrics/MetricsUtils.java

@@ -0,0 +1,48 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed 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 google.registry.monitoring.metrics;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.collect.ImmutableList;
+
+/** Static helper methods for the Metrics library. */
+final class MetricsUtils {
+
+  private static final String LABEL_SIZE_ERROR =
+      "The count of labelValues must be equal to the underlying Metric's count of labels.";
+
+  private MetricsUtils() {}
+
+  /**
+   * Check that the given {@code labelValues} match in count with the count of {@link
+   * LabelDescriptor} instances on the given {@code metric}
+   *
+   * @throws IllegalArgumentException if there is a count mismatch.
+   */
+  static void checkLabelValuesLength(Metric<?> metric, String[] labelValues) {
+    checkArgument(labelValues.length == metric.getMetricSchema().labels().size(), LABEL_SIZE_ERROR);
+  }
+
+  /**
+   * Check that the given {@code labelValues} match in count with the count of {@link
+   * LabelDescriptor} instances on the given {@code metric}
+   *
+   * @throws IllegalArgumentException if there is a count mismatch.
+   */
+  static void checkLabelValuesLength(Metric<?> metric, ImmutableList<String> labelValues) {
+    checkArgument(labelValues.size() == metric.getMetricSchema().labels().size(), LABEL_SIZE_ERROR);
+  }
+}

java/google/registry/monitoring/metrics/StoredMetric.java

@@ -14,7 +14,6 @@
 
 package google.registry.monitoring.metrics;
 
-import static com.google.common.base.Preconditions.checkArgument;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableList;
@@ -41,10 +40,6 @@ import org.joda.time.Instant;
 @ThreadSafe
 public class StoredMetric<V> extends AbstractMetric<V> implements SettableMetric<V> {
 
-  private static final String LABEL_COUNT_ERROR =
-      "The count of labelValues must be equal to the underlying "
-          + "MetricDescriptor's count of labels.";
-
   private final ConcurrentHashMap<ImmutableList<String>, V> values = new ConcurrentHashMap<>();
 
   StoredMetric(
@@ -63,7 +58,7 @@ public class StoredMetric<V> extends AbstractMetric<V> implements SettableMetric
 
   @Override
   public final void set(V value, String... labelValues) {
-    checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
+    MetricsUtils.checkLabelValuesLength(this, labelValues);
 
     set(value, ImmutableList.copyOf(labelValues));
   }

javatests/google/registry/monitoring/metrics/CounterTest.java

@@ -20,14 +20,18 @@ import static org.junit.Assert.fail;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import org.joda.time.Instant;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
 import org.junit.runner.RunWith;
-import org.mockito.runners.MockitoJUnitRunner;
+import org.junit.runners.JUnit4;
 
 /** Unit tests for {@link Counter}. */
-@RunWith(MockitoJUnitRunner.class)
+@RunWith(JUnit4.class)
 public class CounterTest {
 
+  @Rule public final ExpectedException thrown = ExpectedException.none();
+
   @Test
   public void testGetCardinality_reflectsCurrentCardinality() {
     Counter counter =
@@ -56,11 +60,11 @@ public class CounterTest {
             ImmutableSet.of(
                 LabelDescriptor.create("label1", "bar"), LabelDescriptor.create("label2", "bar")));
 
-    try {
+    thrown.expect(IllegalArgumentException.class);
+    thrown.expectMessage(
+        "The count of labelValues must be equal to the underlying Metric's count of labels.");
+
     counter.increment("blah");
-      fail("expected IllegalArgumentException");
-    } catch (IllegalArgumentException expected) {
-    }
   }
 
   @Test

javatests/google/registry/monitoring/metrics/StoredMetricTest.java

@@ -69,7 +69,9 @@ public class StoredMetricTest {
             Boolean.class);
 
     thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("The count of labelValues must be equal to");
+    thrown.expectMessage(
+        "The count of labelValues must be equal to the underlying Metric's count of labels.");
+
     dimensionalMetric.set(true, "foo");
   }