org.eclipse.jetty.http.QuotedQualityCSV Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2016 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 static java.lang.Integer.MIN_VALUE;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.function.Function;
/* ------------------------------------------------------------ */
/**
* Implements a quoted comma separated list of quality values
* in accordance with RFC7230 and RFC7231.
* Values are returned sorted in quality order, with OWS and the
* quality parameters removed.
* @see "https://tools.ietf.org/html/rfc7230#section-3.2.6"
* @see "https://tools.ietf.org/html/rfc7230#section-7"
* @see "https://tools.ietf.org/html/rfc7231#section-5.3.1"
*/
public class QuotedQualityCSV implements Iterable
{
private final static Double ZERO=new Double(0.0);
private final static Double ONE=new Double(1.0);
private enum State { VALUE, PARAM_NAME, PARAM_VALUE, Q_VALUE};
private final List _values = new ArrayList<>();
private final List _quality = new ArrayList<>();
private boolean _sorted = false;
private final Function secondaryOrderingFunction;
/* ------------------------------------------------------------ */
/**
* Sorts values with equal quality according to the length of the value String.
*/
public QuotedQualityCSV()
{
this((s) -> s.length());
}
/**
* Sorts values with equal quality according to given order.
*/
public QuotedQualityCSV(String[] serverPreferredValueOrder)
{
this((s) -> {
for (int i=0;i secondaryOrderingFunction)
{
this.secondaryOrderingFunction = secondaryOrderingFunction;
}
/* ------------------------------------------------------------ */
public void addValue(String value)
{
StringBuffer buffer = new StringBuffer();
int l=value.length();
State state=State.VALUE;
boolean quoted=false;
boolean sloshed=false;
int nws_length=0;
int last_length=0;
Double q=ONE;
for (int i=0;i<=l;i++)
{
char c=i==l?0:value.charAt(i);
// Handle quoting https://tools.ietf.org/html/rfc7230#section-3.2.6
if (quoted && c!=0)
{
if (sloshed)
sloshed=false;
else
{
switch(c)
{
case '\\':
sloshed=true;
break;
case '"':
quoted=false;
if (state==State.Q_VALUE)
continue;
break;
}
}
buffer.append(c);
nws_length=buffer.length();
continue;
}
// Handle common cases
switch(c)
{
case ' ':
case '\t':
if (buffer.length()>last_length) // not leading OWS
buffer.append(c);
continue;
case '"':
quoted=true;
if (state==State.Q_VALUE)
continue;
buffer.append(c);
nws_length=buffer.length();
continue;
case ';':
if (state==State.Q_VALUE)
{
try
{
q=new Double(buffer.substring(last_length));
}
catch(Exception e)
{
q=ZERO;
}
nws_length=last_length;
}
buffer.setLength(nws_length); // trim following OWS
buffer.append(c);
last_length=++nws_length;
state=State.PARAM_NAME;
continue;
case ',':
case 0:
if (state==State.Q_VALUE)
{
try
{
q=new Double(buffer.substring(last_length));
}
catch(Exception e)
{
q=ZERO;
}
nws_length=last_length;
}
buffer.setLength(nws_length); // trim following OWS
if (q>0.0 && nws_length>0)
{
_values.add(buffer.toString());
_quality.add(q);
_sorted=false;
}
buffer.setLength(0);
last_length=0;
nws_length=0;
q=ONE;
state=State.VALUE;
continue;
default:
{
switch (state)
{
case VALUE:
{
buffer.append(c);
nws_length=buffer.length();
continue;
}
case PARAM_NAME:
{
if (c=='=')
{
buffer.setLength(nws_length); // trim following OWS
if (nws_length-last_length==1 && Character.toLowerCase(buffer.charAt(last_length))=='q')
{
buffer.setLength(last_length-1);
nws_length=buffer.length();
last_length=nws_length;
state=State.Q_VALUE;
continue;
}
buffer.append(c);
last_length=++nws_length;
state=State.PARAM_VALUE;
continue;
}
buffer.append(c);
nws_length=buffer.length();
continue;
}
case PARAM_VALUE:
case Q_VALUE:
{
buffer.append(c);
nws_length=buffer.length();
continue;
}
}
}
}
}
}
public List getValues()
{
if (!_sorted)
sort();
return _values;
}
@Override
public Iterator iterator()
{
if (!_sorted)
sort();
return _values.iterator();
}
protected void sort()
{
_sorted=true;
Double last = ZERO;
int lastOrderIndex = Integer.MIN_VALUE;
for (int i = _values.size(); i-- > 0;)
{
String v = _values.get(i);
Double q = _quality.get(i);
int compare=last.compareTo(q);
if (compare>0 || (compare==0 && secondaryOrderingFunction.apply(v)