org.eclipse.jetty.server.InclusiveByteRange 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.server;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
/* ------------------------------------------------------------ */
/** Byte range inclusive of end points.
*
*
* parses the following types of byte ranges:
*
* bytes=100-499
* bytes=-300
* bytes=100-
* bytes=1-2,2-3,6-,-2
*
* given an entity length, converts range to string
*
* bytes 100-499/500
*
*
*
* Based on RFC2616 3.12, 14.16, 14.35.1, 14.35.2
*
* And yes the spec does strangely say that while 10-20, is bytes 10 to 20 and 10- is bytes 10 until the end that -20 IS NOT bytes 0-20, but the last 20 bytes of the content.
*
* @version $version$
*
*/
public class InclusiveByteRange
{
private static final Logger LOG = Log.getLogger(InclusiveByteRange.class);
private long first;
private long last;
public InclusiveByteRange(long first, long last)
{
this.first = first;
this.last = last;
}
public long getFirst()
{
return first;
}
public long getLast()
{
return last;
}
/* ------------------------------------------------------------ */
private void coalesce(InclusiveByteRange r)
{
first = Math.min(first,r.first);
last = Math.max(last,r.last);
}
/* ------------------------------------------------------------ */
private boolean overlaps(InclusiveByteRange range)
{
return (range.first>=this.first && range.first<=this.last)
||
(range.last>=this.first && range.last<=this.last)
||
(range.firstthis.last);
}
/* ------------------------------------------------------------ */
public long getSize()
{
return last-first+1;
}
/* ------------------------------------------------------------ */
public String toHeaderRangeString(long size)
{
StringBuilder sb = new StringBuilder(40);
sb.append("bytes ");
sb.append(first);
sb.append('-');
sb.append(last);
sb.append("/");
sb.append(size);
return sb.toString();
}
/* ------------------------------------------------------------ */
@Override
public int hashCode()
{
return (int)(first ^ last);
}
/* ------------------------------------------------------------ */
@Override
public boolean equals( Object obj )
{
if(obj == null)
return false;
if(!(obj instanceof InclusiveByteRange))
return false;
return ((InclusiveByteRange)obj).first == this.first &&
((InclusiveByteRange)obj).last == this.last;
}
/* ------------------------------------------------------------ */
@Override
public String toString()
{
StringBuilder sb = new StringBuilder(60);
sb.append(Long.toString(first));
sb.append(":");
sb.append(Long.toString(last));
return sb.toString();
}
/* ------------------------------------------------------------ */
/**
* @param headers Enumeration of Range header fields.
* @param size Size of the resource.
* @return List of satisfiable ranges
*/
public static List satisfiableRanges(Enumeration headers, long size)
{
List ranges = null;
final long end = size-1;
// walk through all Range headers
while (headers.hasMoreElements())
{
String header = headers.nextElement();
StringTokenizer tok = new StringTokenizer(header,"=,",false);
String t=null;
try
{
// read all byte ranges for this header
while (tok.hasMoreTokens())
{
try
{
t = tok.nextToken().trim();
if ("bytes".equals(t))
continue;
long first = -1;
long last = -1;
int dash = t.indexOf('-');
if (dash < 0 || t.indexOf("-",dash + 1) >= 0)
{
LOG.warn("Bad range format: {}",t);
break;
}
if (dash>0)
first = Long.parseLong(t.substring(0,dash).trim());
if (dash<(t.length()-1))
last = Long.parseLong(t.substring(dash + 1).trim());
if (first==-1)
{
if (last==-1)
{
LOG.warn("Bad range format: {}",t);
break;
}
if (last==0)
continue;
// This is a suffix range
first = Math.max(0,size-last);
last = end;
}
else
{
// Range starts after end
if (first>=size)
continue;
if (last==-1)
last = end;
else if (last>=end)
last = end;
}
if (last();
boolean coalesced = false;
for (Iterator i = ranges.listIterator(); i.hasNext();)
{
InclusiveByteRange r = i.next();
if (range.overlaps(r))
{
coalesced = true;
r.coalesce(range);
while(i.hasNext())
{
InclusiveByteRange r2 = i.next();
if (r2.overlaps(r))
{
r.coalesce(r2);
i.remove();
}
}
}
}
if (!coalesced)
ranges.add(range);
}
catch (NumberFormatException e)
{
LOG.warn("Bad range format: {}",t);
LOG.ignore(e);
}
}
}
catch(Exception e)
{
LOG.warn("Bad range format: {}",t);
LOG.ignore(e);
}
}
return ranges;
}
/* ------------------------------------------------------------ */
public static String to416HeaderRangeString(long size)
{
StringBuilder sb = new StringBuilder(40);
sb.append("bytes */");
sb.append(size);
return sb.toString();
}
}