Move TraceConfig into its own package, extract inner class TraceParams. (#340)

17 files changed, 250 insertions, 220 deletions

diff --git a/api/src/main/java/io/opencensus/trace/TraceComponent.java b/api/src/main/java/io/opencensus/trace/TraceComponent.java
index 1829417f..bee02dae 100644
--- a/api/src/main/java/io/opencensus/trace/TraceComponent.java
+++ b/api/src/main/java/io/opencensus/trace/TraceComponent.java
@@ -15,6 +15,7 @@ package io.opencensus.trace;
 
 import io.opencensus.common.Clock;
 import io.opencensus.internal.ZeroTimeClock;
+import io.opencensus.trace.config.TraceConfig;
 
 /**
  * Class that holds the implementation instances for {@link Tracer}, {@link
diff --git a/api/src/main/java/io/opencensus/trace/TraceConfig.java b/api/src/main/java/io/opencensus/trace/TraceConfig.java
deleted file mode 100644
index 41fa75b8..00000000
--- a/api/src/main/java/io/opencensus/trace/TraceConfig.java
+++ /dev/null
@@ -1,213 +0,0 @@
-/*
- * Copyright 2017, Google Inc.
- * 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.trace;
-
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
-
-import com.google.auto.value.AutoValue;
-import javax.annotation.concurrent.Immutable;
-
-/**
- * Global configuration of the trace service. This allows users to change configs for the default
- * sampler, maximum events to be kept, etc. (see {@link TraceParams} for details).
- */
-public abstract class TraceConfig {
-  private static final NoopTraceConfig noopTraceConfig = new NoopTraceConfig();
-
-  /**
-   * Returns the active {@code TraceParams}.
-   *
-   * @return the active {@code TraceParams}.
-   */
-  public abstract TraceParams getActiveTraceParams();
-
-  /**
-   * Updates the active {@link TraceParams}.
-   *
-   * @param traceParams the new active {@code TraceParams}.
-   */
-  public abstract void updateActiveTraceParams(TraceParams traceParams);
-
-  /**
-   * Temporary updates the active {@link TraceParams} for {@code durationNs} nanoseconds.
-   *
-   * @param traceParams the new active {@code TraceParams}.
-   * @param durationNs the duration for how long the new params will be active.
-   */
-  public abstract void temporaryUpdateActiveTraceParams(TraceParams traceParams, long durationNs);
-
-  /**
-   * Returns the no-op implementation of the {@code TraceConfig}.
-   *
-   * @return the no-op implementation of the {@code TraceConfig}.
-   */
-  static TraceConfig getNoopTraceConfig() {
-    return noopTraceConfig;
-  }
-
-  /** Class that holds global trace parameters. */
-  @AutoValue
-  @Immutable
-  public abstract static class TraceParams {
-    // These values are the default values for all the global parameters.
-    private static final double DEFAULT_PROBABILITY = 1e-4;
-    private static final Sampler DEFAULT_SAMPLER = Samplers.probabilitySampler(DEFAULT_PROBABILITY);
-    private static final int DEFAULT_SPAN_MAX_NUM_ATTRIBUTES = 32;
-    private static final int DEFAULT_SPAN_MAX_NUM_ANNOTATIONS = 32;
-    private static final int DEFAULT_SPAN_MAX_NUM_NETWORK_EVENTS = 128;
-    private static final int DEFAULT_SPAN_MAX_NUM_LINKS = 128;
-
-    public static final TraceParams DEFAULT =
-        TraceParams.builder()
-            .setSampler(DEFAULT_SAMPLER)
-            .setMaxNumberOfAttributes(DEFAULT_SPAN_MAX_NUM_ATTRIBUTES)
-            .setMaxNumberOfAnnotations(DEFAULT_SPAN_MAX_NUM_ANNOTATIONS)
-            .setMaxNumberOfNetworkEvents(DEFAULT_SPAN_MAX_NUM_NETWORK_EVENTS)
-            .setMaxNumberOfLinks(DEFAULT_SPAN_MAX_NUM_LINKS)
-            .build();
-
-    /**
-     * Returns the global default {@code Sampler}. Used if no {@code Sampler} is provided in {@link
-     * StartSpanOptions}.
-     *
-     * @return the global default {@code Sampler}.
-     */
-    public abstract Sampler getSampler();
-
-    /**
-     * Returns the global default max number of attributes per {@link Span}.
-     *
-     * @return the global default max number of attributes per {@link Span}.
-     */
-    public abstract int getMaxNumberOfAttributes();
-
-    /**
-     * Returns the global default max number of {@link Annotation} events per {@link Span}.
-     *
-     * @return the global default max number of {@code Annotation} events per {@code Span}.
-     */
-    public abstract int getMaxNumberOfAnnotations();
-
-    /**
-     * Returns the global default max number of {@link NetworkEvent} events per {@link Span}.
-     *
-     * @return the global default max number of {@code NetworkEvent} events per {@code Span}.
-     */
-    public abstract int getMaxNumberOfNetworkEvents();
-
-    /**
-     * Returns the global default max number of {@link Link} entries per {@link Span}.
-     *
-     * @return the global default max number of {@code Link} entries per {@code Span}.
-     */
-    public abstract int getMaxNumberOfLinks();
-
-    private static Builder builder() {
-      return new AutoValue_TraceConfig_TraceParams.Builder();
-    }
-
-    /**
-     * Returns a {@link Builder} initialized to the same property values as the current instance.
-     *
-     * @return a {@link Builder} initialized to the same property values as the current instance.
-     */
-    public abstract Builder toBuilder();
-
-    /** A {@code Builder} class for {@link TraceParams}. */
-    @AutoValue.Builder
-    public abstract static class Builder {
-
-      /**
-       * Sets the global default {@code Sampler}. It must be not {@code null} otherwise {@link
-       * #build()} will throw an exception.
-       *
-       * @param sampler the global default {@code Sampler}.
-       * @return this.
-       */
-      public abstract Builder setSampler(Sampler sampler);
-
-      /**
-       * Sets the global default max number of attributes per {@link Span}.
-       *
-       * @param maxNumberOfAttributes the global default max number of attributes per {@link Span}.
-       *     It must be positive otherwise {@link #build()} will throw an exception.
-       * @return this.
-       */
-      public abstract Builder setMaxNumberOfAttributes(int maxNumberOfAttributes);
-
-      /**
-       * Sets the global default max number of {@link Annotation} events per {@link Span}.
-       *
-       * @param maxNumberOfAnnotations the global default max number of {@link Annotation} events
-       *     per {@link Span}. It must be positive otherwise {@link #build()} will throw an
-       *     exception.
-       * @return this.
-       */
-      public abstract Builder setMaxNumberOfAnnotations(int maxNumberOfAnnotations);
-
-      /**
-       * Sets the global default max number of {@link NetworkEvent} events per {@link Span}.
-       *
-       * @param maxNumberOfNetworkEvents the global default max number of {@link NetworkEvent}
-       *     events per {@link Span}. It must be positive otherwise {@link #build()} will throw an
-       *     exception.
-       * @return this.
-       */
-      public abstract Builder setMaxNumberOfNetworkEvents(int maxNumberOfNetworkEvents);
-
-      /**
-       * Sets the global default max number of {@link Link} entries per {@link Span}.
-       *
-       * @param maxNumberOfLinks the global default max number of {@link Link} entries per {@link
-       *     Span}. It must be positive otherwise {@link #build()} will throw an exception.
-       * @return this.
-       */
-      public abstract Builder setMaxNumberOfLinks(int maxNumberOfLinks);
-
-      abstract TraceParams autoBuild();
-
-      /**
-       * Builds and returns a {@code TraceParams} with the desired values.
-       *
-       * @return a {@code TraceParams} with the desired values.
-       * @throws NullPointerException if the sampler is {@code null}.
-       * @throws IllegalArgumentException if any of the max numbers are not positive.
-       */
-      public TraceParams build() {
-        TraceParams traceParams = autoBuild();
-        checkNotNull(traceParams.getSampler(), "sampler");
-        checkArgument(traceParams.getMaxNumberOfAttributes() > 0, "maxNumberOfAttributes");
-        checkArgument(traceParams.getMaxNumberOfAnnotations() > 0, "maxNumberOfAnnotations");
-        checkArgument(traceParams.getMaxNumberOfNetworkEvents() > 0, "maxNumberOfNetworkEvents");
-        checkArgument(traceParams.getMaxNumberOfLinks() > 0, "maxNumberOfLinks");
-        return traceParams;
-      }
-    }
-  }
-
-  private static final class NoopTraceConfig extends TraceConfig {
-
-    @Override
-    public TraceParams getActiveTraceParams() {
-      return TraceParams.DEFAULT;
-    }
-
-    @Override
-    public void updateActiveTraceParams(TraceParams traceParams) {}
-
-    @Override
-    public void temporaryUpdateActiveTraceParams(TraceParams traceParams, long durationNs) {}
-  }
-}
diff --git a/api/src/main/java/io/opencensus/trace/Tracing.java b/api/src/main/java/io/opencensus/trace/Tracing.java
index e6d34a45..771b8553 100644
--- a/api/src/main/java/io/opencensus/trace/Tracing.java
+++ b/api/src/main/java/io/opencensus/trace/Tracing.java
@@ -16,6 +16,7 @@ package io.opencensus.trace;
 import com.google.common.annotations.VisibleForTesting;
 import io.opencensus.common.Clock;
 import io.opencensus.internal.Provider;
+import io.opencensus.trace.config.TraceConfig;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
diff --git a/api/src/main/java/io/opencensus/trace/config/TraceConfig.java b/api/src/main/java/io/opencensus/trace/config/TraceConfig.java
new file mode 100644
index 00000000..80f206c9
--- /dev/null
+++ b/api/src/main/java/io/opencensus/trace/config/TraceConfig.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2017, Google Inc.
+ * 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.trace.config;
+
+/**
+ * Global configuration of the trace service. This allows users to change configs for the default
+ * sampler, maximum events to be kept, etc. (see {@link TraceParams} for details).
+ */
+public abstract class TraceConfig {
+  private static final NoopTraceConfig NOOP_TRACE_CONFIG = new NoopTraceConfig();
+
+  /**
+   * Returns the active {@code TraceParams}.
+   *
+   * @return the active {@code TraceParams}.
+   */
+  public abstract TraceParams getActiveTraceParams();
+
+  /**
+   * Updates the active {@link TraceParams}.
+   *
+   * @param traceParams the new active {@code TraceParams}.
+   */
+  public abstract void updateActiveTraceParams(TraceParams traceParams);
+
+  /**
+   * Temporary updates the active {@link TraceParams} for {@code durationNs} nanoseconds.
+   *
+   * @param traceParams the new active {@code TraceParams}.
+   * @param durationNs the duration for how long the new params will be active.
+   */
+  public abstract void temporaryUpdateActiveTraceParams(TraceParams traceParams, long durationNs);
+
+  /**
+   * Returns the no-op implementation of the {@code TraceConfig}.
+   *
+   * @return the no-op implementation of the {@code TraceConfig}.
+   */
+  public static TraceConfig getNoopTraceConfig() {
+    return NOOP_TRACE_CONFIG;
+  }
+
+  private static final class NoopTraceConfig extends TraceConfig {
+
+    @Override
+    public TraceParams getActiveTraceParams() {
+      return TraceParams.DEFAULT;
+    }
+
+    @Override
+    public void updateActiveTraceParams(TraceParams traceParams) {}
+
+    @Override
+    public void temporaryUpdateActiveTraceParams(TraceParams traceParams, long durationNs) {}
+  }
+}
diff --git a/api/src/main/java/io/opencensus/trace/config/TraceParams.java b/api/src/main/java/io/opencensus/trace/config/TraceParams.java
new file mode 100644
index 00000000..c4463342
--- /dev/null
+++ b/api/src/main/java/io/opencensus/trace/config/TraceParams.java
@@ -0,0 +1,165 @@
+/*
+ * Copyright 2017, Google Inc.
+ * 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.trace.config;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.auto.value.AutoValue;
+import io.opencensus.trace.Annotation;
+import io.opencensus.trace.Link;
+import io.opencensus.trace.NetworkEvent;
+import io.opencensus.trace.Sampler;
+import io.opencensus.trace.Samplers;
+import io.opencensus.trace.Span;
+import io.opencensus.trace.StartSpanOptions;
+import javax.annotation.concurrent.Immutable;
+
+/** Class that holds global trace parameters. */
+@AutoValue
+@Immutable
+public abstract class TraceParams {
+  // These values are the default values for all the global parameters.
+  private static final double DEFAULT_PROBABILITY = 1e-4;
+  private static final Sampler DEFAULT_SAMPLER = Samplers.probabilitySampler(DEFAULT_PROBABILITY);
+  private static final int DEFAULT_SPAN_MAX_NUM_ATTRIBUTES = 32;
+  private static final int DEFAULT_SPAN_MAX_NUM_ANNOTATIONS = 32;
+  private static final int DEFAULT_SPAN_MAX_NUM_NETWORK_EVENTS = 128;
+  private static final int DEFAULT_SPAN_MAX_NUM_LINKS = 128;
+
+  public static final TraceParams DEFAULT =
+      TraceParams.builder()
+          .setSampler(DEFAULT_SAMPLER)
+          .setMaxNumberOfAttributes(DEFAULT_SPAN_MAX_NUM_ATTRIBUTES)
+          .setMaxNumberOfAnnotations(DEFAULT_SPAN_MAX_NUM_ANNOTATIONS)
+          .setMaxNumberOfNetworkEvents(DEFAULT_SPAN_MAX_NUM_NETWORK_EVENTS)
+          .setMaxNumberOfLinks(DEFAULT_SPAN_MAX_NUM_LINKS)
+          .build();
+
+  /**
+   * Returns the global default {@code Sampler}. Used if no {@code Sampler} is provided in {@link
+   * StartSpanOptions}.
+   *
+   * @return the global default {@code Sampler}.
+   */
+  public abstract Sampler getSampler();
+
+  /**
+   * Returns the global default max number of attributes per {@link Span}.
+   *
+   * @return the global default max number of attributes per {@link Span}.
+   */
+  public abstract int getMaxNumberOfAttributes();
+
+  /**
+   * Returns the global default max number of {@link Annotation} events per {@link Span}.
+   *
+   * @return the global default max number of {@code Annotation} events per {@code Span}.
+   */
+  public abstract int getMaxNumberOfAnnotations();
+
+  /**
+   * Returns the global default max number of {@link NetworkEvent} events per {@link Span}.
+   *
+   * @return the global default max number of {@code NetworkEvent} events per {@code Span}.
+   */
+  public abstract int getMaxNumberOfNetworkEvents();
+
+  /**
+   * Returns the global default max number of {@link Link} entries per {@link Span}.
+   *
+   * @return the global default max number of {@code Link} entries per {@code Span}.
+   */
+  public abstract int getMaxNumberOfLinks();
+
+  private static Builder builder() {
+    return new AutoValue_TraceParams.Builder();
+  }
+
+  /**
+   * Returns a {@link Builder} initialized to the same property values as the current instance.
+   *
+   * @return a {@link Builder} initialized to the same property values as the current instance.
+   */
+  public abstract Builder toBuilder();
+
+  /** A {@code Builder} class for {@link TraceParams}. */
+  @AutoValue.Builder
+  public abstract static class Builder {
+
+    /**
+     * Sets the global default {@code Sampler}. It must be not {@code null} otherwise {@link
+     * #build()} will throw an exception.
+     *
+     * @param sampler the global default {@code Sampler}.
+     * @return this.
+     */
+    public abstract Builder setSampler(Sampler sampler);
+
+    /**
+     * Sets the global default max number of attributes per {@link Span}.
+     *
+     * @param maxNumberOfAttributes the global default max number of attributes per {@link Span}.
+     *     It must be positive otherwise {@link #build()} will throw an exception.
+     * @return this.
+     */
+    public abstract Builder setMaxNumberOfAttributes(int maxNumberOfAttributes);
+
+    /**
+     * Sets the global default max number of {@link Annotation} events per {@link Span}.
+     *
+     * @param maxNumberOfAnnotations the global default max number of {@link Annotation} events
+     *     per {@link Span}. It must be positive otherwise {@link #build()} will throw an
+     *     exception.
+     * @return this.
+     */
+    public abstract Builder setMaxNumberOfAnnotations(int maxNumberOfAnnotations);
+
+    /**
+     * Sets the global default max number of {@link NetworkEvent} events per {@link Span}.
+     *
+     * @param maxNumberOfNetworkEvents the global default max number of {@link NetworkEvent}
+     *     events per {@link Span}. It must be positive otherwise {@link #build()} will throw an
+     *     exception.
+     * @return this.
+     */
+    public abstract Builder setMaxNumberOfNetworkEvents(int maxNumberOfNetworkEvents);
+
+    /**
+     * Sets the global default max number of {@link Link} entries per {@link Span}.
+     *
+     * @param maxNumberOfLinks the global default max number of {@link Link} entries per {@link
+     *     Span}. It must be positive otherwise {@link #build()} will throw an exception.
+     * @return this.
+     */
+    public abstract Builder setMaxNumberOfLinks(int maxNumberOfLinks);
+
+    abstract TraceParams autoBuild();
+
+    /**
+     * Builds and returns a {@code TraceParams} with the desired values.
+     *
+     * @return a {@code TraceParams} with the desired values.
+     * @throws NullPointerException if the sampler is {@code null}.
+     * @throws IllegalArgumentException if any of the max numbers are not positive.
+     */
+    public TraceParams build() {
+      TraceParams traceParams = autoBuild();
+      checkArgument(traceParams.getMaxNumberOfAttributes() > 0, "maxNumberOfAttributes");
+      checkArgument(traceParams.getMaxNumberOfAnnotations() > 0, "maxNumberOfAnnotations");
+      checkArgument(traceParams.getMaxNumberOfNetworkEvents() > 0, "maxNumberOfNetworkEvents");
+      checkArgument(traceParams.getMaxNumberOfLinks() > 0, "maxNumberOfLinks");
+      return traceParams;
+    }
+  }
+}
diff --git a/api/src/test/java/io/opencensus/trace/TraceComponentTest.java b/api/src/test/java/io/opencensus/trace/TraceComponentTest.java
index 106cb965..cd42a98a 100644
--- a/api/src/test/java/io/opencensus/trace/TraceComponentTest.java
+++ b/api/src/test/java/io/opencensus/trace/TraceComponentTest.java
@@ -16,6 +16,7 @@ package io.opencensus.trace;
 import static com.google.common.truth.Truth.assertThat;
 
 import io.opencensus.internal.ZeroTimeClock;
+import io.opencensus.trace.config.TraceConfig;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
diff --git a/api/src/test/java/io/opencensus/trace/TraceParamsTest.java b/api/src/test/java/io/opencensus/trace/TraceParamsTest.java
index 60f40deb..e21485e1 100644
--- a/api/src/test/java/io/opencensus/trace/TraceParamsTest.java
+++ b/api/src/test/java/io/opencensus/trace/TraceParamsTest.java
@@ -15,7 +15,7 @@ package io.opencensus.trace;
 
 import static com.google.common.truth.Truth.assertThat;
 
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceParams;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
diff --git a/api/src/test/java/io/opencensus/trace/TracingTest.java b/api/src/test/java/io/opencensus/trace/TracingTest.java
index b7c9be25..c23e7c6f 100644
--- a/api/src/test/java/io/opencensus/trace/TracingTest.java
+++ b/api/src/test/java/io/opencensus/trace/TracingTest.java
@@ -15,6 +15,7 @@ package io.opencensus.trace;
 
 import static com.google.common.truth.Truth.assertThat;
 
+import io.opencensus.trace.config.TraceConfig;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
diff --git a/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java b/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
index 695a2215..703b5b3b 100644
--- a/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
+++ b/core_impl/src/main/java/io/opencensus/trace/SpanFactoryImpl.java
@@ -18,7 +18,8 @@ import static com.google.common.base.Preconditions.checkNotNull;
 import io.opencensus.common.Clock;
 import io.opencensus.trace.Link.Type;
 import io.opencensus.trace.Span.Options;
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceConfig;
+import io.opencensus.trace.config.TraceParams;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Random;
diff --git a/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java b/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java
index 2fcb7cb7..6eab0ccc 100644
--- a/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java
+++ b/core_impl/src/main/java/io/opencensus/trace/SpanImpl.java
@@ -19,7 +19,7 @@ import static com.google.common.base.Preconditions.checkState;
 import com.google.common.collect.EvictingQueue;
 import io.opencensus.common.Clock;
 import io.opencensus.trace.SpanData.TimedEvent;
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceParams;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.EnumSet;
diff --git a/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java b/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
index 7e25dada..c313d1e1 100644
--- a/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
+++ b/core_impl/src/main/java/io/opencensus/trace/TraceComponentImplBase.java
@@ -15,6 +15,7 @@ package io.opencensus.trace;
 
 import io.opencensus.common.Clock;
 import io.opencensus.common.EventQueue;
+import io.opencensus.trace.config.TraceConfig;
 
 /** Base implementation of the {@link TraceComponent}. */
 class TraceComponentImplBase extends TraceComponent {
diff --git a/core_impl/src/main/java/io/opencensus/trace/TraceConfigImpl.java b/core_impl/src/main/java/io/opencensus/trace/TraceConfigImpl.java
index eef2be79..673c4c8a 100644
--- a/core_impl/src/main/java/io/opencensus/trace/TraceConfigImpl.java
+++ b/core_impl/src/main/java/io/opencensus/trace/TraceConfigImpl.java
@@ -13,6 +13,9 @@
 
 package io.opencensus.trace;
 
+import io.opencensus.trace.config.TraceConfig;
+import io.opencensus.trace.config.TraceParams;
+
 /**
  * Global configuration of the trace service. This allows users to change configs for the default
  * sampler, maximum events to be kept, etc.
diff --git a/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java b/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java
index 996607ce..7b550cc1 100644
--- a/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java
+++ b/core_impl/src/main/java/io/opencensus/trace/TracerImpl.java
@@ -14,6 +14,7 @@
 package io.opencensus.trace;
 
 import io.opencensus.common.Clock;
+import io.opencensus.trace.config.TraceConfig;
 
 /** Implementation of the {@link Tracer}. */
 final class TracerImpl extends Tracer {
diff --git a/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java b/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
index bc2bbfb2..e93d30c2 100644
--- a/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
+++ b/core_impl/src/test/java/io/opencensus/trace/SpanFactoryImplTest.java
@@ -19,7 +19,8 @@ import static org.mockito.Mockito.when;
 import io.opencensus.internal.TestClock;
 import io.opencensus.trace.Span.Options;
 import io.opencensus.trace.SpanImpl.StartEndHandler;
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceConfig;
+import io.opencensus.trace.config.TraceParams;
 import java.util.Random;
 import org.junit.Before;
 import org.junit.Test;
diff --git a/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java b/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java
index 6c9d57fc..81fd8316 100644
--- a/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java
+++ b/core_impl/src/test/java/io/opencensus/trace/SpanImplTest.java
@@ -20,7 +20,7 @@ import io.opencensus.common.Timestamp;
 import io.opencensus.internal.TestClock;
 import io.opencensus.trace.Span.Options;
 import io.opencensus.trace.SpanImpl.StartEndHandler;
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceParams;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.Map;
diff --git a/core_impl/src/test/java/io/opencensus/trace/TraceConfigImplTest.java b/core_impl/src/test/java/io/opencensus/trace/TraceConfigImplTest.java
index 6e43cbb4..9872dd61 100644
--- a/core_impl/src/test/java/io/opencensus/trace/TraceConfigImplTest.java
+++ b/core_impl/src/test/java/io/opencensus/trace/TraceConfigImplTest.java
@@ -15,7 +15,7 @@ package io.opencensus.trace;
 
 import static com.google.common.truth.Truth.assertThat;
 
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceParams;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
diff --git a/core_impl/src/test/java/io/opencensus/trace/TraceExporterImplTest.java b/core_impl/src/test/java/io/opencensus/trace/TraceExporterImplTest.java
index 4684bef8..4c181e5f 100644
--- a/core_impl/src/test/java/io/opencensus/trace/TraceExporterImplTest.java
+++ b/core_impl/src/test/java/io/opencensus/trace/TraceExporterImplTest.java
@@ -20,7 +20,7 @@ import static org.mockito.Mockito.doThrow;
 import io.opencensus.common.MillisClock;
 import io.opencensus.common.SimpleEventQueue;
 import io.opencensus.trace.Span.Options;
-import io.opencensus.trace.TraceConfig.TraceParams;
+import io.opencensus.trace.config.TraceParams;
 import io.opencensus.trace.TraceExporter.ServiceHandler;
 import java.util.ArrayList;
 import java.util.Collection;