1 files changed, 117 insertions, 0 deletions
diff --git a/java/org/brotli/integration/Benchmark.java b/java/org/brotli/integration/Benchmark.java
new file mode 100644
index 0000000..d44e161
--- /dev/null
+++ b/java/org/brotli/integration/Benchmark.java
@@ -0,0 +1,117 @@
+package org.brotli.integration;
+
+import org.brotli.dec.BrotliInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.ArrayList;
+
+/**
+ * Measures decompression speed on the given corpus.
+ */
+public class Benchmark {
+  private static byte[] readFile(String fileName) throws IOException {
+    int bufferLength = 65536;
+    byte[] buffer = new byte[bufferLength];
+    ByteArrayOutputStream baos = new ByteArrayOutputStream();
+    FileInputStream fin = new FileInputStream(fileName);
+    try {
+      int bytesRead;
+      while ((bytesRead = fin.read(buffer)) >= 0) {
+        baos.write(buffer, 0, bytesRead);
+      }
+    } finally {
+      fin.close();
+    }
+    return baos.toByteArray();
+  }
+  
+  private static long decodeBytes(InputStream input, OutputStream output, byte[] buffer)
+      throws IOException {
+    long totalOut = 0;
+    int readBytes;
+    BrotliInputStream in = new BrotliInputStream(input);
+    try {
+      while ((readBytes = in.read(buffer)) >= 0) {
+        output.write(buffer, 0, readBytes);
+        totalOut += readBytes;
+      }
+    } finally {
+      in.close();
+    }
+    return totalOut;
+  }
+
+  public static void main(String... args) throws IOException {
+    if (args.length == 0) {
+      System.out.println("Usage: benchmark <corpus>");
+      return;
+    }
+    File corpusDir = new File(args[0]);
+    ArrayList<String> fileNames = new ArrayList<String>();
+    File[] filesList = corpusDir.listFiles();
+    if (filesList == null) {
+      System.out.println("'" + args[0] + "' is not a directory");
+      return;
+    }
+    for (File file : filesList) {
+      if (!file.isFile()) {
+        continue;
+      }
+      String fileName = file.getAbsolutePath();
+      if (!fileName.endsWith(".brotli")) {
+        continue;
+      }
+      fileNames.add(fileName);
+    }
+    int fileCount = fileNames.size();
+    if (fileCount == 0) {
+      System.out.println("No files found");
+      return;
+    }
+    byte[][] files = new byte[fileCount][];
+    for (int i = 0; i < fileCount; ++i) {
+      files[i] = readFile(fileNames.get(i));
+    }
+
+    ByteArrayOutputStream baos = new ByteArrayOutputStream(65536);
+    byte[] buffer = new byte[65536];
+
+    int warmupRepeat = 10;
+    long bytesDecoded = 0;
+    for (int i = 0; i < warmupRepeat; ++i) {
+      bytesDecoded = 0;
+      for (int j = 0; j < fileCount; ++j) {
+        baos.reset();
+        bytesDecoded += decodeBytes(new ByteArrayInputStream(files[j]), baos, buffer);
+      }
+    }
+
+    int repeat = 100;
+
+    long bestTime = Long.MAX_VALUE;
+    for (int i = 0; i < repeat; ++i) {
+      long start = System.nanoTime();
+      for (int j = 0; j < fileCount; ++j) {
+        baos.reset();
+        decodeBytes(new ByteArrayInputStream(files[j]), baos, buffer);
+      }
+      long end = System.nanoTime();
+      long timeDelta = end - start;
+      if (timeDelta < bestTime) {
+        bestTime = timeDelta;
+      }
+    }
+
+    double timeDeltaSeconds = bestTime / 1000000000.0;
+    if (timeDeltaSeconds <= 0) {
+      return;
+    }
+    double mbDecoded = bytesDecoded / (1024.0 * 1024.0);
+    System.out.println(mbDecoded / timeDeltaSeconds);
+  }
+}