1 files changed, 64 insertions, 0 deletions
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..ff701e20
--- /dev/null
+++ b/api/src/main/java/io/opencensus/trace/config/TraceConfig.java
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2017, 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.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).
+ *
+ * @since 0.5
+ */
+public abstract class TraceConfig {
+  private static final NoopTraceConfig NOOP_TRACE_CONFIG = new NoopTraceConfig();
+
+  /**
+   * Returns the active {@code TraceParams}.
+   *
+   * @return the active {@code TraceParams}.
+   * @since 0.5
+   */
+  public abstract TraceParams getActiveTraceParams();
+
+  /**
+   * Updates the active {@link TraceParams}.
+   *
+   * @param traceParams the new active {@code TraceParams}.
+   * @since 0.5
+   */
+  public abstract void updateActiveTraceParams(TraceParams traceParams);
+
+  /**
+   * Returns the no-op implementation of the {@code TraceConfig}.
+   *
+   * @return the no-op implementation of the {@code TraceConfig}.
+   * @since 0.5
+   */
+  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) {}
+  }
+}