Add JMH encoding benchmark

Author: patrickfav

pom.xml

@@ -215,6 +215,18 @@
             <version>4.12</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>1.21</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>1.21</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
     <developers>
         <developer>

src/main/java/at/favre/lib/bytes/BaseEncoding.java

@@ -151,7 +151,7 @@ private int decodeTo(byte[] target, CharSequence chars) {
         return bytesWritten;
     }
 
-    private static final class Alphabet {
+    static final class Alphabet {
         // this is meant to be immutable -- don't modify it!
         private final char[] chars;
         final int mask;

src/test/java/at/favre/lib/bytes/EncodingJmhBenchmark.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2018 Patrick Favre-Bulle
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 at.favre.lib.bytes;
+
+import org.openjdk.jmh.annotations.*;
+
+import java.nio.ByteOrder;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Random;
+import java.util.concurrent.TimeUnit;
+
+/*
+# JMH version: 1.21
+# VM version: JDK 1.8.0_172, Java HotSpot(TM) 64-Bit Server VM, 25.172-b11
+# i7 7700K / 24G
+
+Benchmark                               (byteLength)   Mode  Cnt         Score        Error  Units
+EncodingJmhBenchmark.encodeBase64Guava             1  thrpt    4  10361634,745 ± 152739,710  ops/s
+EncodingJmhBenchmark.encodeBase64Guava            16  thrpt    4   4360485,804 ±  44729,417  ops/s
+EncodingJmhBenchmark.encodeBase64Guava           128  thrpt    4    790407,010 ±   8095,476  ops/s
+EncodingJmhBenchmark.encodeBase64Guava           512  thrpt    4    192448,674 ±   2196,035  ops/s
+EncodingJmhBenchmark.encodeBase64Guava       1000000  thrpt    4       102,780 ±      2,949  ops/s
+EncodingJmhBenchmark.encodeBase64Okio              1  thrpt    4  12658987,399 ± 361955,366  ops/s
+EncodingJmhBenchmark.encodeBase64Okio             16  thrpt    4   7059404,777 ± 293665,348  ops/s
+EncodingJmhBenchmark.encodeBase64Okio            128  thrpt    4   1749131,031 ±  85915,325  ops/s
+EncodingJmhBenchmark.encodeBase64Okio            512  thrpt    4    239764,488 ±   6204,540  ops/s
+EncodingJmhBenchmark.encodeBase64Okio        1000000  thrpt    4       107,868 ±      0,569  ops/s
+ */
+
+@State(Scope.Thread)
+@Fork(1)
+@Warmup(iterations = 2, time = 2)
+@Measurement(iterations = 4, time = 5)
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.SECONDS)
+public class EncodingJmhBenchmark {
+
+    @Param({"1", "16", "128", "512", "1000000"})
+    private int byteLength;
+    private Map<Integer, Bytes[]> rndMap;
+
+    private BinaryToTextEncoding.EncoderDecoder base64Okio;
+    private BinaryToTextEncoding.EncoderDecoder base64Guava;
+    private Random random;
+
+    @Setup(Level.Trial)
+    public void setup() {
+        random = new Random();
+        base64Okio = new BinaryToTextEncoding.Base64Encoding();
+        base64Guava = new BaseEncoding(new BaseEncoding.Alphabet("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray()), BaseEncoding.BASE32_RFC4848_PADDING);
+        rndMap = new HashMap<>();
+        int[] lengths = new int[]{1, 16, 128, 512, 1000000};
+        for (int length : lengths) {
+            int count = 10;
+            rndMap.put(length, new Bytes[count]);
+            for (int i = 0; i < count; i++) {
+                rndMap.get(length)[i] = Bytes.random(length);
+            }
+        }
+    }
+
+    @Benchmark
+    public byte[] encodeBase64Okio() {
+        return encodeDecode(base64Okio);
+    }
+
+    @Benchmark
+    public byte[] encodeBase64Guava() {
+        return encodeDecode(base64Guava);
+    }
+
+    private byte[] encodeDecode(BinaryToTextEncoding.EncoderDecoder encoder) {
+        Bytes[] bytes = rndMap.get(byteLength);
+        int rndNum = random.nextInt(bytes.length);
+
+        String encoded = encoder.encode(bytes[rndNum].array(), ByteOrder.BIG_ENDIAN);
+        return encoder.decode(encoded);
+    }
+}