Add benchmark for BaseEncoding.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81099316

Author: lowasser

guava-tests/benchmark/com/google/common/io/BaseEncodingBenchmark.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2014 The Guava 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 com.google.common.io;
+
+import com.google.caliper.BeforeExperiment;
+import com.google.caliper.Benchmark;
+import com.google.caliper.Param;
+
+import java.util.Random;
+
+/**
+ * Benchmark for {@code BaseEncoding} performance.
+ */
+public class BaseEncodingBenchmark {
+  enum EncodingOption {
+    BASE64(BaseEncoding.base64()),
+    BASE64_URL(BaseEncoding.base64Url()),
+    BASE32(BaseEncoding.base32()),
+    BASE32_HEX(BaseEncoding.base32Hex()),
+    BASE16(BaseEncoding.base16());
+    
+    final BaseEncoding encoding;
+    
+    EncodingOption(BaseEncoding encoding) {
+      this.encoding = encoding;
+    }
+  }
+  
+  @Param
+  EncodingOption encoding;
+  
+  @Param({"10", "100", "10000"})
+  int n;
+  
+  private final byte[][] inputs = new byte[0x1000][];
+
+  @BeforeExperiment
+  public void setUp() {
+    Random rng = new Random();
+    for (int i = 0; i < inputs.length; i++) {
+      inputs[i] = new byte[n];
+      rng.nextBytes(inputs[i]);
+    }
+  }
+  
+  @Benchmark public int encode(int reps) {
+    int tmp = 0;
+    for (int i = 0; i < reps; i++) {
+      tmp += System.identityHashCode(encoding.encoding.encode(inputs[i & 0xFFF]));
+    }
+    return tmp;
+  }
+}