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//
// ========================================================================
// Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.spdy.parser;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import org.junit.Assert;
import org.junit.Ignore;
import org.junit.Test;
public class ParseVersusCacheBenchmarkTest
{
@Ignore
@Test
public void testParseVersusCache() throws Exception
{
// The parser knows the header name and value lengths, so it creates strings
// out of the bytes; however, this involves creating a byte[] copy the bytes,
// and creating a new String.
// The alternative is to use a cache<ByteBuffer, String>. Is that faster ?
// See also: http://jeremymanson.blogspot.com/2008/04/immutability-in-java.html
String name = "Content-Type";
String value = "application/octect-stream";
ByteBuffer buffer = ByteBuffer.wrap((name + value).getBytes(StandardCharsets.ISO_8859_1));
int iterations = 100_000_000;
long begin = System.nanoTime();
for (int i = 0; i < iterations; ++i)
{
byte[] nameBytes = new byte[name.length()];
buffer.get(nameBytes);
String name2 = new String(nameBytes, StandardCharsets.ISO_8859_1);
Assert.assertEquals(name2, name);
byte[] valueBytes = new byte[value.length()];
buffer.get(valueBytes);
String value2 = new String(valueBytes, StandardCharsets.ISO_8859_1);
Assert.assertEquals(value2, value);
buffer.flip();
}
long end = System.nanoTime();
System.err.printf("parse time: %d%n", TimeUnit.NANOSECONDS.toMillis(end - begin));
Map<ByteBuffer, String> map = new HashMap<>();
map.put(ByteBuffer.wrap(name.getBytes(StandardCharsets.ISO_8859_1)), name);
map.put(ByteBuffer.wrap(value.getBytes(StandardCharsets.ISO_8859_1)), value);
final Map<ByteBuffer, String> cache = Collections.unmodifiableMap(map);
begin = System.nanoTime();
for (int i = 0; i < iterations; ++i)
{
buffer.limit(buffer.position() + name.length());
String name2 = cache.get(buffer);
Assert.assertEquals(name2, name);
buffer.position(buffer.limit());
buffer.limit(buffer.position() + value.length());
String value2 = cache.get(buffer);
Assert.assertEquals(value2, value);
buffer.position(buffer.limit());
buffer.flip();
}
end = System.nanoTime();
System.err.printf("cache time: %d%n", TimeUnit.NANOSECONDS.toMillis(end - begin));
}
}
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