Introduce BlazeInterners, a Blaze-specific wrapper around Guava's Interners that makes an appropriate call to Interners.InternerBuilder#concurrencyLevel.

For current readers of this CL, I used this class everywhere in the Blaze codebase.

For future readers of this CL, this class should be used to create an Interner in the Blaze codebase.

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MOS_MIGRATED_REVID=140063271

1 files changed, 35 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/concurrent/BlazeInterners.java b/src/main/java/com/google/devtools/build/lib/concurrent/BlazeInterners.java
new file mode 100644
index 0000000000..d54793d8e1
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/concurrent/BlazeInterners.java
@@ -0,0 +1,35 @@
+// Copyright 2016 The Bazel 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 com.google.devtools.build.lib.concurrent;
+
+import com.google.common.collect.Interner;
+import com.google.common.collect.Interners;
+import com.google.common.collect.Interners.InternerBuilder;
+
+/** Wrapper around {@link Interners}, with Blaze-specific predetermined concurrency levels. */
+public class BlazeInterners {
+  private static final int CONCURRENCY_LEVEL = Runtime.getRuntime().availableProcessors();
+
+  private static InternerBuilder setConcurrencyLevel(InternerBuilder builder) {
+    return builder.concurrencyLevel(CONCURRENCY_LEVEL);
+  }
+
+  public static <T> Interner<T> newWeakInterner() {
+    return setConcurrencyLevel(Interners.newBuilder().weak()).build();
+  }
+
+  public static <T> Interner<T> newStrongInterner() {
+    return setConcurrencyLevel(Interners.newBuilder().strong()).build();
+  }
+}