Temporarily move "metrics" package into impl_core/ for release. (#1426)

The "metrics" package isn't ready to be released yet, so this commit moves it
out of the API artifact.  The package can still be accessed by the stats
implementation in impl_core/.  This commit can be reverted once the package is
ready to be exposed.  The moved package names also contain "temporary" so that
there is no possibility of class name conflicts between different versions of
opencensus-api and opencensus-impl-core.  For example,
io.opencensus.metrics.export is renamed to
io.opencensus.implcore.temporary.metrics.export.

13 files changed, 0 insertions, 1326 deletions

diff --git a/api/src/test/java/io/opencensus/metrics/DistributionTest.java b/api/src/test/java/io/opencensus/metrics/DistributionTest.java
deleted file mode 100644
index d511e317..00000000
--- a/api/src/test/java/io/opencensus/metrics/DistributionTest.java
+++ /dev/null
@@ -1,226 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.common.Timestamp;
-import io.opencensus.metrics.Distribution.Bucket;
-import io.opencensus.metrics.Distribution.Exemplar;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link Value}. */
-@RunWith(JUnit4.class)
-public class DistributionTest {
-
-  @Rule public final ExpectedException thrown = ExpectedException.none();
-
-  private static final Timestamp TIMESTAMP = Timestamp.create(1, 0);
-  private static final Map<String, String> ATTACHMENTS = Collections.singletonMap("key", "value");
-
-  @Test
-  public void createAndGet_Bucket() {
-    Bucket bucket = Bucket.create(98);
-    assertThat(bucket.getCount()).isEqualTo(98);
-    assertThat(bucket.getExemplar()).isNull();
-  }
-
-  @Test
-  public void createAndGet_BucketWithExemplar() {
-    Exemplar exemplar = Exemplar.create(12.2, TIMESTAMP, ATTACHMENTS);
-    Bucket bucket = Bucket.create(7, exemplar);
-    assertThat(bucket.getCount()).isEqualTo(7);
-    assertThat(bucket.getExemplar()).isEqualTo(exemplar);
-  }
-
-  @Test
-  public void createBucket_preventNullExemplar() {
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("exemplar");
-    Bucket.create(1, null);
-  }
-
-  @Test
-  public void createAndGet_Exemplar() {
-    Exemplar exemplar = Exemplar.create(-9.9, TIMESTAMP, ATTACHMENTS);
-    assertThat(exemplar.getValue()).isEqualTo(-9.9);
-    assertThat(exemplar.getTimestamp()).isEqualTo(TIMESTAMP);
-    assertThat(exemplar.getAttachments()).isEqualTo(ATTACHMENTS);
-  }
-
-  @Test
-  public void createAndGet_Distribution() {
-    Exemplar exemplar = Exemplar.create(15.0, TIMESTAMP, ATTACHMENTS);
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(
-            Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4, exemplar));
-    Distribution distribution = Distribution.create(6.6, 10, 678.54, bucketBounds, buckets);
-    assertThat(distribution.getMean()).isEqualTo(6.6);
-    assertThat(distribution.getCount()).isEqualTo(10);
-    assertThat(distribution.getSumOfSquaredDeviations()).isEqualTo(678.54);
-    assertThat(distribution.getBucketBoundaries())
-        .containsExactlyElementsIn(bucketBounds)
-        .inOrder();
-    assertThat(distribution.getBuckets()).containsExactlyElementsIn(buckets).inOrder();
-  }
-
-  @Test
-  public void createBucket_NegativeCount() {
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("bucket count should be non-negative.");
-    Bucket.create(-5);
-  }
-
-  @Test
-  public void createExemplar_PreventNullAttachments() {
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("attachments");
-    Exemplar.create(15, TIMESTAMP, null);
-  }
-
-  @Test
-  public void createExemplar_PreventNullAttachmentKey() {
-    Map<String, String> attachments = Collections.singletonMap(null, "value");
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("key of attachment");
-    Exemplar.create(15, TIMESTAMP, attachments);
-  }
-
-  @Test
-  public void createExemplar_PreventNullAttachmentValue() {
-    Map<String, String> attachments = Collections.singletonMap("key", null);
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("value of attachment");
-    Exemplar.create(15, TIMESTAMP, attachments);
-  }
-
-  @Test
-  public void createDistribution_NegativeCount() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4));
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("count should be non-negative.");
-    Distribution.create(6.6, -10, 678.54, bucketBounds, buckets);
-  }
-
-  @Test
-  public void createDistribution_NegativeSumOfSquaredDeviations() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(0), Bucket.create(0), Bucket.create(0), Bucket.create(0));
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("sum of squared deviations should be non-negative.");
-    Distribution.create(6.6, 0, -678.54, bucketBounds, buckets);
-  }
-
-  @Test
-  public void createDistribution_ZeroCountAndPositiveMean() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(0), Bucket.create(0), Bucket.create(0), Bucket.create(0));
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("mean should be 0 if count is 0.");
-    Distribution.create(6.6, 0, 0, bucketBounds, buckets);
-  }
-
-  @Test
-  public void createDistribution_ZeroCountAndSumOfSquaredDeviations() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(0), Bucket.create(0), Bucket.create(0), Bucket.create(0));
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("sum of squared deviations should be 0 if count is 0.");
-    Distribution.create(0, 0, 678.54, bucketBounds, buckets);
-  }
-
-  @Test
-  public void createDistribution_NullBucketBounds() {
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4));
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("bucketBoundaries list should not be null.");
-    Distribution.create(6.6, 10, 678.54, null, buckets);
-  }
-
-  @Test
-  public void createDistribution_UnorderedBucketBounds() {
-    List<Double> bucketBounds = Arrays.asList(0.0, -1.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4));
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage("bucket boundaries not sorted.");
-    Distribution.create(6.6, 10, 678.54, bucketBounds, buckets);
-  }
-
-  @Test
-  public void createDistribution_NullBucketList() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("bucket list should not be null.");
-    Distribution.create(6.6, 10, 678.54, bucketBounds, null);
-  }
-
-  @Test
-  public void createDistribution_NullBucket() {
-    List<Double> bucketBounds = Arrays.asList(-1.0, 0.0, 1.0);
-    List<Bucket> buckets =
-        Arrays.asList(Bucket.create(3), Bucket.create(1), null, Bucket.create(4));
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage("bucket should not be null.");
-    Distribution.create(6.6, 10, 678.54, bucketBounds, buckets);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(
-            Distribution.create(
-                10,
-                10,
-                1,
-                Arrays.asList(-5.0, 0.0, 5.0),
-                Arrays.asList(
-                    Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4))),
-            Distribution.create(
-                10,
-                10,
-                1,
-                Arrays.asList(-5.0, 0.0, 5.0),
-                Arrays.asList(
-                    Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4))))
-        .addEqualityGroup(
-            Distribution.create(
-                -7,
-                10,
-                23.456,
-                Arrays.asList(-5.0, 0.0, 5.0),
-                Arrays.asList(
-                    Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4))))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/LabelKeyTest.java b/api/src/test/java/io/opencensus/metrics/LabelKeyTest.java
deleted file mode 100644
index 83f2b59a..00000000
--- a/api/src/test/java/io/opencensus/metrics/LabelKeyTest.java
+++ /dev/null
@@ -1,86 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import java.util.Arrays;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link LabelKey}. */
-@RunWith(JUnit4.class)
-public class LabelKeyTest {
-
-  private static final LabelKey KEY = LabelKey.create("key", "description");
-
-  @Test
-  public void testGetKey() {
-    assertThat(KEY.getKey()).isEqualTo("key");
-  }
-
-  @Test
-  public void testGetDescription() {
-    assertThat(KEY.getDescription()).isEqualTo("description");
-  }
-
-  @Test
-  public void create_NoLengthConstraint() {
-    // We have a length constraint of 256-characters for TagKey. That constraint doesn't apply to
-    // LabelKey.
-    char[] chars = new char[300];
-    Arrays.fill(chars, 'k');
-    String key = new String(chars);
-    assertThat(LabelKey.create(key, "").getKey()).isEqualTo(key);
-  }
-
-  @Test
-  public void create_WithUnprintableChars() {
-    String key = "\2ab\3cd";
-    String description = "\4ef\5gh";
-    LabelKey labelKey = LabelKey.create(key, description);
-    assertThat(labelKey.getKey()).isEqualTo(key);
-    assertThat(labelKey.getDescription()).isEqualTo(description);
-  }
-
-  @Test
-  public void create_WithNonAsciiChars() {
-    String key = "键";
-    String description = "测试用键";
-    LabelKey nonAsciiKey = LabelKey.create(key, description);
-    assertThat(nonAsciiKey.getKey()).isEqualTo(key);
-    assertThat(nonAsciiKey.getDescription()).isEqualTo(description);
-  }
-
-  @Test
-  public void create_Empty() {
-    LabelKey emptyKey = LabelKey.create("", "");
-    assertThat(emptyKey.getKey()).isEmpty();
-    assertThat(emptyKey.getDescription()).isEmpty();
-  }
-
-  @Test
-  public void testLabelKeyEquals() {
-    new EqualsTester()
-        .addEqualityGroup(LabelKey.create("foo", ""), LabelKey.create("foo", ""))
-        .addEqualityGroup(LabelKey.create("foo", "description"))
-        .addEqualityGroup(LabelKey.create("bar", ""))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/LabelValueTest.java b/api/src/test/java/io/opencensus/metrics/LabelValueTest.java
deleted file mode 100644
index e5526b2f..00000000
--- a/api/src/test/java/io/opencensus/metrics/LabelValueTest.java
+++ /dev/null
@@ -1,74 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import java.util.Arrays;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link LabelValue}. */
-@RunWith(JUnit4.class)
-public class LabelValueTest {
-
-  private static final LabelValue VALUE = LabelValue.create("value");
-  private static final LabelValue UNSET = LabelValue.create(null);
-  private static final LabelValue EMPTY = LabelValue.create("");
-
-  @Test
-  public void testGetValue() {
-    assertThat(VALUE.getValue()).isEqualTo("value");
-    assertThat(UNSET.getValue()).isNull();
-    assertThat(EMPTY.getValue()).isEmpty();
-  }
-
-  @Test
-  public void create_NoLengthConstraint() {
-    // We have a length constraint of 256-characters for TagValue. That constraint doesn't apply to
-    // LabelValue.
-    char[] chars = new char[300];
-    Arrays.fill(chars, 'v');
-    String value = new String(chars);
-    assertThat(LabelValue.create(value).getValue()).isEqualTo(value);
-  }
-
-  @Test
-  public void create_WithUnprintableChars() {
-    String value = "\2ab\3cd";
-    assertThat(LabelValue.create(value).getValue()).isEqualTo(value);
-  }
-
-  @Test
-  public void create_WithNonAsciiChars() {
-    String value = "值";
-    LabelValue nonAsciiValue = LabelValue.create(value);
-    assertThat(nonAsciiValue.getValue()).isEqualTo(value);
-  }
-
-  @Test
-  public void testLabelValueEquals() {
-    new EqualsTester()
-        .addEqualityGroup(LabelValue.create("foo"), LabelValue.create("foo"))
-        .addEqualityGroup(UNSET)
-        .addEqualityGroup(EMPTY)
-        .addEqualityGroup(LabelValue.create("bar"))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/MetricDescriptorTest.java b/api/src/test/java/io/opencensus/metrics/MetricDescriptorTest.java
deleted file mode 100644
index 9c0a42fc..00000000
--- a/api/src/test/java/io/opencensus/metrics/MetricDescriptorTest.java
+++ /dev/null
@@ -1,102 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.metrics.MetricDescriptor.Type;
-import java.util.Arrays;
-import java.util.List;
-import org.hamcrest.CoreMatchers;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link MetricDescriptor}. */
-@RunWith(JUnit4.class)
-public class MetricDescriptorTest {
-
-  @Rule public final ExpectedException thrown = ExpectedException.none();
-
-  private static final String METRIC_NAME_1 = "metric1";
-  private static final String METRIC_NAME_2 = "metric2";
-  private static final String DESCRIPTION = "Metric description.";
-  private static final String UNIT = "kb/s";
-  private static final LabelKey KEY_1 = LabelKey.create("key1", "some key");
-  private static final LabelKey KEY_2 = LabelKey.create("key2", "some other key");
-
-  @Test
-  public void testGet() {
-    MetricDescriptor metricDescriptor =
-        MetricDescriptor.create(
-            METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, Arrays.asList(KEY_1, KEY_2));
-    assertThat(metricDescriptor.getName()).isEqualTo(METRIC_NAME_1);
-    assertThat(metricDescriptor.getDescription()).isEqualTo(DESCRIPTION);
-    assertThat(metricDescriptor.getUnit()).isEqualTo(UNIT);
-    assertThat(metricDescriptor.getType()).isEqualTo(Type.GAUGE_DOUBLE);
-    assertThat(metricDescriptor.getLabelKeys()).containsExactly(KEY_1, KEY_2).inOrder();
-  }
-
-  @Test
-  public void preventNullLabelKeyList() {
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("labelKeys"));
-    MetricDescriptor.create(METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, null);
-  }
-
-  @Test
-  public void preventNullLabelKey() {
-    List<LabelKey> keys = Arrays.asList(KEY_1, null);
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("labelKey"));
-    MetricDescriptor.create(METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, keys);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(
-            MetricDescriptor.create(
-                METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, Arrays.asList(KEY_1, KEY_2)),
-            MetricDescriptor.create(
-                METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, Arrays.asList(KEY_1, KEY_2)))
-        .addEqualityGroup(
-            MetricDescriptor.create(
-                METRIC_NAME_2, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, Arrays.asList(KEY_1, KEY_2)))
-        .addEqualityGroup(
-            MetricDescriptor.create(
-                METRIC_NAME_2, DESCRIPTION, UNIT, Type.GAUGE_INT64, Arrays.asList(KEY_1, KEY_2)))
-        .addEqualityGroup(
-            MetricDescriptor.create(
-                METRIC_NAME_1,
-                DESCRIPTION,
-                UNIT,
-                Type.CUMULATIVE_DISTRIBUTION,
-                Arrays.asList(KEY_1, KEY_2)))
-        .addEqualityGroup(
-            MetricDescriptor.create(
-                METRIC_NAME_1,
-                DESCRIPTION,
-                UNIT,
-                Type.CUMULATIVE_DISTRIBUTION,
-                Arrays.asList(KEY_1)))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java b/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java
deleted file mode 100644
index 49e8ce02..00000000
--- a/api/src/test/java/io/opencensus/metrics/MetricRegistryTest.java
+++ /dev/null
@@ -1,185 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import io.opencensus.common.ToDoubleFunction;
-import io.opencensus.common.ToLongFunction;
-import java.util.LinkedHashMap;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link MetricRegistry}. */
-@RunWith(JUnit4.class)
-public class MetricRegistryTest {
-  @Rule public ExpectedException thrown = ExpectedException.none();
-
-  private final MetricRegistry metricRegistry =
-      MetricsComponent.newNoopMetricsComponent().getMetricRegistry();
-
-  @Test
-  public void addDoubleGauge_NullName() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addDoubleGauge(
-        null,
-        "description",
-        "1",
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToDoubleFunction<Object>() {
-          @Override
-          public double applyAsDouble(Object value) {
-            return 5.0;
-          }
-        });
-  }
-
-  @Test
-  public void addDoubleGauge_NullDescription() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addDoubleGauge(
-        "name",
-        null,
-        "1",
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToDoubleFunction<Object>() {
-          @Override
-          public double applyAsDouble(Object value) {
-            return 5.0;
-          }
-        });
-  }
-
-  @Test
-  public void addDoubleGauge_NullUnit() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addDoubleGauge(
-        "name",
-        "description",
-        null,
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToDoubleFunction<Object>() {
-          @Override
-          public double applyAsDouble(Object value) {
-            return 5.0;
-          }
-        });
-  }
-
-  @Test
-  public void addDoubleGauge_NullLabels() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addDoubleGauge(
-        "name",
-        "description",
-        "1",
-        null,
-        null,
-        new ToDoubleFunction<Object>() {
-          @Override
-          public double applyAsDouble(Object value) {
-            return 5.0;
-          }
-        });
-  }
-
-  @Test
-  public void addDoubleGauge_NullFunction() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addDoubleGauge(
-        "name", "description", "1", new LinkedHashMap<LabelKey, LabelValue>(), null, null);
-  }
-
-  @Test
-  public void addLongGauge_NullName() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addLongGauge(
-        null,
-        "description",
-        "1",
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToLongFunction<Object>() {
-          @Override
-          public long applyAsLong(Object value) {
-            return 5;
-          }
-        });
-  }
-
-  @Test
-  public void addLongGauge_NullDescription() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addLongGauge(
-        "name",
-        null,
-        "1",
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToLongFunction<Object>() {
-          @Override
-          public long applyAsLong(Object value) {
-            return 5;
-          }
-        });
-  }
-
-  @Test
-  public void addLongGauge_NullUnit() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addLongGauge(
-        "name",
-        "description",
-        null,
-        new LinkedHashMap<LabelKey, LabelValue>(),
-        null,
-        new ToLongFunction<Object>() {
-          @Override
-          public long applyAsLong(Object value) {
-            return 5;
-          }
-        });
-  }
-
-  @Test
-  public void addLongGauge_NullLabels() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addLongGauge(
-        "name",
-        "description",
-        "1",
-        null,
-        null,
-        new ToLongFunction<Object>() {
-          @Override
-          public long applyAsLong(Object value) {
-            return 5;
-          }
-        });
-  }
-
-  @Test
-  public void addLongGauge_NullFunction() {
-    thrown.expect(NullPointerException.class);
-    metricRegistry.addLongGauge(
-        "name", "description", "1", new LinkedHashMap<LabelKey, LabelValue>(), null, null);
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/MetricTest.java b/api/src/test/java/io/opencensus/metrics/MetricTest.java
deleted file mode 100644
index 37deed4b..00000000
--- a/api/src/test/java/io/opencensus/metrics/MetricTest.java
+++ /dev/null
@@ -1,116 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.common.Timestamp;
-import io.opencensus.metrics.MetricDescriptor.Type;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link Metric}. */
-@RunWith(JUnit4.class)
-public class MetricTest {
-
-  @Rule public final ExpectedException thrown = ExpectedException.none();
-
-  private static final String METRIC_NAME_1 = "metric1";
-  private static final String METRIC_NAME_2 = "metric2";
-  private static final String DESCRIPTION = "Metric description.";
-  private static final String UNIT = "kb/s";
-  private static final LabelKey KEY_1 = LabelKey.create("key1", "some key");
-  private static final LabelKey KEY_2 = LabelKey.create("key1", "some other key");
-  private static final MetricDescriptor METRIC_DESCRIPTOR_1 =
-      MetricDescriptor.create(
-          METRIC_NAME_1, DESCRIPTION, UNIT, Type.GAUGE_DOUBLE, Arrays.asList(KEY_1, KEY_2));
-  private static final MetricDescriptor METRIC_DESCRIPTOR_2 =
-      MetricDescriptor.create(
-          METRIC_NAME_2, DESCRIPTION, UNIT, Type.CUMULATIVE_INT64, Arrays.asList(KEY_1));
-  private static final LabelValue LABEL_VALUE_1 = LabelValue.create("value1");
-  private static final LabelValue LABEL_VALUE_2 = LabelValue.create("value1");
-  private static final LabelValue LABEL_VALUE_EMPTY = LabelValue.create("");
-  private static final Value VALUE_LONG = Value.longValue(12345678);
-  private static final Value VALUE_DOUBLE_1 = Value.doubleValue(-345.77);
-  private static final Value VALUE_DOUBLE_2 = Value.doubleValue(133.79);
-  private static final Timestamp TIMESTAMP_1 = Timestamp.fromMillis(1000);
-  private static final Timestamp TIMESTAMP_2 = Timestamp.fromMillis(2000);
-  private static final Timestamp TIMESTAMP_3 = Timestamp.fromMillis(3000);
-  private static final Point POINT_1 = Point.create(VALUE_DOUBLE_1, TIMESTAMP_2);
-  private static final Point POINT_2 = Point.create(VALUE_DOUBLE_2, TIMESTAMP_3);
-  private static final Point POINT_3 = Point.create(VALUE_LONG, TIMESTAMP_3);
-  private static final TimeSeries GAUGE_TIME_SERIES_1 =
-      TimeSeries.create(Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), null);
-  private static final TimeSeries GAUGE_TIME_SERIES_2 =
-      TimeSeries.create(Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_2), null);
-  private static final TimeSeries CUMULATIVE_TIME_SERIES =
-      TimeSeries.create(Arrays.asList(LABEL_VALUE_EMPTY), Arrays.asList(POINT_3), TIMESTAMP_1);
-
-  @Test
-  public void testGet() {
-    Metric metric =
-        Metric.create(METRIC_DESCRIPTOR_1, Arrays.asList(GAUGE_TIME_SERIES_1, GAUGE_TIME_SERIES_2));
-    assertThat(metric.getMetricDescriptor()).isEqualTo(METRIC_DESCRIPTOR_1);
-    assertThat(metric.getTimeSeriesList())
-        .containsExactly(GAUGE_TIME_SERIES_1, GAUGE_TIME_SERIES_2)
-        .inOrder();
-  }
-
-  @Test
-  public void typeMismatch_GaugeDouble_Long() {
-    typeMismatch(
-        METRIC_DESCRIPTOR_1,
-        Arrays.asList(CUMULATIVE_TIME_SERIES),
-        String.format("Type mismatch: %s, %s.", Type.GAUGE_DOUBLE, "ValueLong"));
-  }
-
-  @Test
-  public void typeMismatch_CumulativeInt64_Double() {
-    typeMismatch(
-        METRIC_DESCRIPTOR_2,
-        Arrays.asList(GAUGE_TIME_SERIES_1),
-        String.format("Type mismatch: %s, %s.", Type.CUMULATIVE_INT64, "ValueDouble"));
-  }
-
-  private void typeMismatch(
-      MetricDescriptor metricDescriptor, List<TimeSeries> timeSeriesList, String errorMessage) {
-    thrown.expect(IllegalArgumentException.class);
-    thrown.expectMessage(errorMessage);
-    Metric.create(metricDescriptor, timeSeriesList);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(
-            Metric.create(
-                METRIC_DESCRIPTOR_1, Arrays.asList(GAUGE_TIME_SERIES_1, GAUGE_TIME_SERIES_2)),
-            Metric.create(
-                METRIC_DESCRIPTOR_1, Arrays.asList(GAUGE_TIME_SERIES_1, GAUGE_TIME_SERIES_2)))
-        .addEqualityGroup(Metric.create(METRIC_DESCRIPTOR_1, Collections.<TimeSeries>emptyList()))
-        .addEqualityGroup(Metric.create(METRIC_DESCRIPTOR_2, Arrays.asList(CUMULATIVE_TIME_SERIES)))
-        .addEqualityGroup(Metric.create(METRIC_DESCRIPTOR_2, Collections.<TimeSeries>emptyList()))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/MetricsComponentTest.java b/api/src/test/java/io/opencensus/metrics/MetricsComponentTest.java
deleted file mode 100644
index 1c4e70f7..00000000
--- a/api/src/test/java/io/opencensus/metrics/MetricsComponentTest.java
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import io.opencensus.metrics.export.ExportComponent;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link MetricsComponent}. */
-@RunWith(JUnit4.class)
-public class MetricsComponentTest {
-  @Test
-  public void defaultExportComponent() {
-    assertThat(MetricsComponent.newNoopMetricsComponent().getExportComponent())
-        .isInstanceOf(ExportComponent.newNoopExportComponent().getClass());
-  }
-
-  @Test
-  public void defaultMetricRegistry() {
-    assertThat(MetricsComponent.newNoopMetricsComponent().getMetricRegistry())
-        .isInstanceOf(MetricRegistry.newNoopMetricRegistry().getClass());
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/MetricsTest.java b/api/src/test/java/io/opencensus/metrics/MetricsTest.java
deleted file mode 100644
index 9e0eee1f..00000000
--- a/api/src/test/java/io/opencensus/metrics/MetricsTest.java
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import io.opencensus.metrics.export.ExportComponent;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link Metrics}. */
-@RunWith(JUnit4.class)
-public class MetricsTest {
-  @Rule public ExpectedException thrown = ExpectedException.none();
-
-  @Test
-  public void loadMetricsComponent_UsesProvidedClassLoader() {
-    final RuntimeException toThrow = new RuntimeException("UseClassLoader");
-    thrown.expect(RuntimeException.class);
-    thrown.expectMessage("UseClassLoader");
-    Metrics.loadMetricsComponent(
-        new ClassLoader() {
-          @Override
-          public Class<?> loadClass(String name) {
-            throw toThrow;
-          }
-        });
-  }
-
-  @Test
-  public void loadMetricsComponent_IgnoresMissingClasses() {
-    ClassLoader classLoader =
-        new ClassLoader() {
-          @Override
-          public Class<?> loadClass(String name) throws ClassNotFoundException {
-            throw new ClassNotFoundException();
-          }
-        };
-    assertThat(Metrics.loadMetricsComponent(classLoader).getClass().getName())
-        .isEqualTo("io.opencensus.metrics.MetricsComponent$NoopMetricsComponent");
-  }
-
-  @Test
-  public void defaultExportComponent() {
-    assertThat(Metrics.getExportComponent())
-        .isInstanceOf(ExportComponent.newNoopExportComponent().getClass());
-  }
-
-  @Test
-  public void defaultMetricRegistry() {
-    assertThat(Metrics.getMetricRegistry())
-        .isInstanceOf(MetricRegistry.newNoopMetricRegistry().getClass());
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/PointTest.java b/api/src/test/java/io/opencensus/metrics/PointTest.java
deleted file mode 100644
index cb6175c1..00000000
--- a/api/src/test/java/io/opencensus/metrics/PointTest.java
+++ /dev/null
@@ -1,68 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.common.Timestamp;
-import io.opencensus.metrics.Distribution.Bucket;
-import java.util.Arrays;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link Point}. */
-@RunWith(JUnit4.class)
-public class PointTest {
-
-  private static final Value DOUBLE_VALUE = Value.doubleValue(55.5);
-  private static final Value LONG_VALUE = Value.longValue(9876543210L);
-  private static final Value DISTRIBUTION_VALUE =
-      Value.distributionValue(
-          Distribution.create(
-              6.6,
-              10,
-              678.54,
-              Arrays.asList(-1.0, 0.0, 1.0),
-              Arrays.asList(
-                  Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4))));
-  private static final Timestamp TIMESTAMP_1 = Timestamp.create(1, 2);
-  private static final Timestamp TIMESTAMP_2 = Timestamp.create(3, 4);
-  private static final Timestamp TIMESTAMP_3 = Timestamp.create(5, 6);
-
-  @Test
-  public void testGet() {
-    Point point = Point.create(DOUBLE_VALUE, TIMESTAMP_1);
-    assertThat(point.getValue()).isEqualTo(DOUBLE_VALUE);
-    assertThat(point.getTimestamp()).isEqualTo(TIMESTAMP_1);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(
-            Point.create(DOUBLE_VALUE, TIMESTAMP_1), Point.create(DOUBLE_VALUE, TIMESTAMP_1))
-        .addEqualityGroup(Point.create(LONG_VALUE, TIMESTAMP_1))
-        .addEqualityGroup(Point.create(LONG_VALUE, TIMESTAMP_2))
-        .addEqualityGroup(
-            Point.create(DISTRIBUTION_VALUE, TIMESTAMP_2),
-            Point.create(DISTRIBUTION_VALUE, TIMESTAMP_2))
-        .addEqualityGroup(Point.create(DISTRIBUTION_VALUE, TIMESTAMP_3))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/TimeSeriesTest.java b/api/src/test/java/io/opencensus/metrics/TimeSeriesTest.java
deleted file mode 100644
index 07dff97d..00000000
--- a/api/src/test/java/io/opencensus/metrics/TimeSeriesTest.java
+++ /dev/null
@@ -1,116 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.common.Timestamp;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import org.hamcrest.CoreMatchers;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link TimeSeries}. */
-@RunWith(JUnit4.class)
-public class TimeSeriesTest {
-
-  @Rule public ExpectedException thrown = ExpectedException.none();
-
-  private static final LabelValue LABEL_VALUE_1 = LabelValue.create("value1");
-  private static final LabelValue LABEL_VALUE_2 = LabelValue.create("value2");
-  private static final Value VALUE_LONG = Value.longValue(12345678);
-  private static final Value VALUE_DOUBLE = Value.doubleValue(-345.77);
-  private static final Timestamp TIMESTAMP_1 = Timestamp.fromMillis(1000);
-  private static final Timestamp TIMESTAMP_2 = Timestamp.fromMillis(2000);
-  private static final Timestamp TIMESTAMP_3 = Timestamp.fromMillis(3000);
-  private static final Point POINT_1 = Point.create(VALUE_DOUBLE, TIMESTAMP_2);
-  private static final Point POINT_2 = Point.create(VALUE_LONG, TIMESTAMP_3);
-
-  @Test
-  public void testGet_TimeSeries() {
-    TimeSeries cumulativeTimeSeries =
-        TimeSeries.create(
-            Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), TIMESTAMP_1);
-    assertThat(cumulativeTimeSeries.getStartTimestamp()).isEqualTo(TIMESTAMP_1);
-    assertThat(cumulativeTimeSeries.getLabelValues())
-        .containsExactly(LABEL_VALUE_1, LABEL_VALUE_2)
-        .inOrder();
-    assertThat(cumulativeTimeSeries.getPoints()).containsExactly(POINT_1).inOrder();
-  }
-
-  @Test
-  public void create_WithNullLabelValueList() {
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("labelValues"));
-    TimeSeries.create(null, Collections.<Point>emptyList(), TIMESTAMP_1);
-  }
-
-  @Test
-  public void create_WithNullLabelValue() {
-    List<LabelValue> labelValues = Arrays.asList(LABEL_VALUE_1, null);
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("labelValue"));
-    TimeSeries.create(labelValues, Collections.<Point>emptyList(), TIMESTAMP_1);
-  }
-
-  @Test
-  public void create_WithNullPointList() {
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("points"));
-    TimeSeries.create(Collections.<LabelValue>emptyList(), null, TIMESTAMP_1);
-  }
-
-  @Test
-  public void create_WithNullPoint() {
-    List<Point> points = Arrays.asList(POINT_1, null);
-    thrown.expect(NullPointerException.class);
-    thrown.expectMessage(CoreMatchers.equalTo("point"));
-    TimeSeries.create(Collections.<LabelValue>emptyList(), points, TIMESTAMP_1);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), TIMESTAMP_1),
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), TIMESTAMP_1))
-        .addEqualityGroup(
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), null),
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), null))
-        .addEqualityGroup(
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1, LABEL_VALUE_2), Arrays.asList(POINT_1), TIMESTAMP_2))
-        .addEqualityGroup(
-            TimeSeries.create(Arrays.asList(LABEL_VALUE_1), Arrays.asList(POINT_1), TIMESTAMP_2))
-        .addEqualityGroup(
-            TimeSeries.create(Arrays.asList(LABEL_VALUE_1), Arrays.asList(POINT_2), TIMESTAMP_2))
-        .addEqualityGroup(
-            TimeSeries.create(
-                Arrays.asList(LABEL_VALUE_1), Arrays.asList(POINT_1, POINT_2), TIMESTAMP_2))
-        .testEquals();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/ValueTest.java b/api/src/test/java/io/opencensus/metrics/ValueTest.java
deleted file mode 100644
index 63430b28..00000000
--- a/api/src/test/java/io/opencensus/metrics/ValueTest.java
+++ /dev/null
@@ -1,128 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.common.testing.EqualsTester;
-import io.opencensus.common.Function;
-import io.opencensus.common.Functions;
-import io.opencensus.metrics.Distribution.Bucket;
-import io.opencensus.metrics.Value.ValueDistribution;
-import io.opencensus.metrics.Value.ValueDouble;
-import io.opencensus.metrics.Value.ValueLong;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link Value}. */
-@RunWith(JUnit4.class)
-public class ValueTest {
-
-  private static final Distribution DISTRIBUTION =
-      Distribution.create(
-          10,
-          10,
-          1,
-          Arrays.asList(-5.0, 0.0, 5.0),
-          Arrays.asList(Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4)));
-
-  @Test
-  public void createAndGet_ValueDouble() {
-    Value value = Value.doubleValue(-34.56);
-    assertThat(value).isInstanceOf(ValueDouble.class);
-    assertThat(((ValueDouble) value).getValue()).isEqualTo(-34.56);
-  }
-
-  @Test
-  public void createAndGet_ValueLong() {
-    Value value = Value.longValue(123456789);
-    assertThat(value).isInstanceOf(ValueLong.class);
-    assertThat(((ValueLong) value).getValue()).isEqualTo(123456789);
-  }
-
-  @Test
-  public void createAndGet_ValueDistribution() {
-    Value value = Value.distributionValue(DISTRIBUTION);
-    assertThat(value).isInstanceOf(ValueDistribution.class);
-    assertThat(((ValueDistribution) value).getValue()).isEqualTo(DISTRIBUTION);
-  }
-
-  @Test
-  public void testEquals() {
-    new EqualsTester()
-        .addEqualityGroup(Value.doubleValue(1.0), Value.doubleValue(1.0))
-        .addEqualityGroup(Value.doubleValue(2.0))
-        .addEqualityGroup(Value.longValue(1L))
-        .addEqualityGroup(Value.longValue(2L))
-        .addEqualityGroup(
-            Value.distributionValue(
-                Distribution.create(
-                    -7,
-                    10,
-                    23.456,
-                    Arrays.asList(-5.0, 0.0, 5.0),
-                    Arrays.asList(
-                        Bucket.create(3), Bucket.create(1), Bucket.create(2), Bucket.create(4)))))
-        .testEquals();
-  }
-
-  @Test
-  public void testMatch() {
-    List<Value> values =
-        Arrays.asList(
-            ValueDouble.create(1.0), ValueLong.create(-1), ValueDistribution.create(DISTRIBUTION));
-    List<Number> expected =
-        Arrays.<Number>asList(1.0, -1L, 10.0, 10L, 1.0, -5.0, 0.0, 5.0, 3L, 1L, 2L, 4L);
-    final List<Number> actual = new ArrayList<Number>();
-    for (Value value : values) {
-      value.match(
-          new Function<Double, Object>() {
-            @Override
-            public Object apply(Double arg) {
-              actual.add(arg);
-              return null;
-            }
-          },
-          new Function<Long, Object>() {
-            @Override
-            public Object apply(Long arg) {
-              actual.add(arg);
-              return null;
-            }
-          },
-          new Function<Distribution, Object>() {
-            @Override
-            public Object apply(Distribution arg) {
-              actual.add(arg.getMean());
-              actual.add(arg.getCount());
-              actual.add(arg.getSumOfSquaredDeviations());
-              actual.addAll(arg.getBucketBoundaries());
-              for (Bucket bucket : arg.getBuckets()) {
-                actual.add(bucket.getCount());
-              }
-              return null;
-            }
-          },
-          Functions.throwAssertionError());
-    }
-    assertThat(actual).containsExactlyElementsIn(expected).inOrder();
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/export/ExportComponentTest.java b/api/src/test/java/io/opencensus/metrics/export/ExportComponentTest.java
deleted file mode 100644
index 15c6e883..00000000
--- a/api/src/test/java/io/opencensus/metrics/export/ExportComponentTest.java
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics.export;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link ExportComponent}. */
-@RunWith(JUnit4.class)
-public class ExportComponentTest {
-  @Test
-  public void defaultMetricExporter() {
-    assertThat(ExportComponent.newNoopExportComponent().getMetricProducerManager())
-        .isInstanceOf(MetricProducerManager.class);
-  }
-}
diff --git a/api/src/test/java/io/opencensus/metrics/export/MetricProducerManagerTest.java b/api/src/test/java/io/opencensus/metrics/export/MetricProducerManagerTest.java
deleted file mode 100644
index 07854927..00000000
--- a/api/src/test/java/io/opencensus/metrics/export/MetricProducerManagerTest.java
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * Copyright 2018, OpenCensus Authors
- *
- * 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 io.opencensus.metrics.export;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import io.opencensus.metrics.MetricProducer;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
-
-/** Unit tests for {@link MetricProducerManager}. */
-@RunWith(JUnit4.class)
-public class MetricProducerManagerTest {
-  private final MetricProducerManager metricProducerManager =
-      MetricProducerManager.newNoopMetricProducerManager();
-  @Mock private MetricProducer metricProducer;
-
-  @Rule public final ExpectedException thrown = ExpectedException.none();
-
-  @Before
-  public void setUp() {
-    MockitoAnnotations.initMocks(this);
-  }
-
-  @Test
-  public void add_DisallowsNull() {
-    thrown.expect(NullPointerException.class);
-    metricProducerManager.add(null);
-  }
-
-  @Test
-  public void add() {
-    metricProducerManager.add(metricProducer);
-    assertThat(metricProducerManager.getAllMetricProducer()).isEmpty();
-  }
-
-  @Test
-  public void addAndRemove() {
-    metricProducerManager.add(metricProducer);
-    assertThat(metricProducerManager.getAllMetricProducer()).isEmpty();
-    metricProducerManager.remove(metricProducer);
-    assertThat(metricProducerManager.getAllMetricProducer()).isEmpty();
-  }
-
-  @Test
-  public void remove_DisallowsNull() {
-    thrown.expect(NullPointerException.class);
-    metricProducerManager.remove(null);
-  }
-
-  @Test
-  public void remove_FromEmpty() {
-    metricProducerManager.remove(metricProducer);
-    assertThat(metricProducerManager.getAllMetricProducer()).isEmpty();
-  }
-
-  @Test
-  public void getAllMetricProducer_empty() {
-    assertThat(metricProducerManager.getAllMetricProducer()).isEmpty();
-  }
-}