org.eclipse.jetty.http.PreEncodedHttpField Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2018 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.http;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.ServiceLoader;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
/* ------------------------------------------------------------ */
/** Pre encoded HttpField.
* A HttpField that will be cached and used many times can be created as
* a {@link PreEncodedHttpField}, which will use the {@link HttpFieldPreEncoder}
* instances discovered by the {@link ServiceLoader} to pre-encode the header
* for each version of HTTP in use. This will save garbage
* and CPU each time the field is encoded into a response.
*
*/
public class PreEncodedHttpField extends HttpField
{
private final static Logger LOG = Log.getLogger(PreEncodedHttpField.class);
private final static HttpFieldPreEncoder[] __encoders;
static
{
List encoders = new ArrayList<>();
Iterator iter = ServiceLoader.load(HttpFieldPreEncoder.class).iterator();
while (iter.hasNext())
{
try
{
HttpFieldPreEncoder encoder = iter.next();
if (index(encoder.getHttpVersion())>=0)
encoders.add(encoder);
}
catch(Error|RuntimeException e)
{
LOG.debug(e);
}
}
LOG.debug("HttpField encoders loaded: {}",encoders);
int size=encoders.size();
__encoders = new HttpFieldPreEncoder[size==0?1:size];
for (HttpFieldPreEncoder e:encoders)
{
int i = index(e.getHttpVersion());
if (__encoders[i]==null)
__encoders[i] = e;
else
LOG.warn("multiple PreEncoders for "+e.getHttpVersion());
}
// Always support HTTP1
if (__encoders[0]==null)
__encoders[0] = new Http1FieldPreEncoder();
}
private static int index(HttpVersion version)
{
switch (version)
{
case HTTP_1_0:
case HTTP_1_1:
return 0;
case HTTP_2:
return 1;
default:
return -1;
}
}
private final byte[][] _encodedField=new byte[__encoders.length][];
public PreEncodedHttpField(HttpHeader header,String name,String value)
{
super(header,name, value);
for (int i=0;i<__encoders.length;i++)
_encodedField[i]=__encoders[i].getEncodedField(header,name,value);
}
public PreEncodedHttpField(HttpHeader header,String value)
{
this(header,header.asString(),value);
}
public PreEncodedHttpField(String name,String value)
{
this(null,name,value);
}
public void putTo(ByteBuffer bufferInFillMode, HttpVersion version)
{
bufferInFillMode.put(_encodedField[index(version)]);
}
}