Eclipse
/
jetty.project
mirror of https://github.com/jetty/jetty.project.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Optimized memory usage of AttributesMap. 

Attributes are used rarely, so AttributesMap was creating a ConcurrentHashMap
that was never used.
In cases where AttributesMap is heavily used (for example CometD) this proved
to save a significant amount of memory footprint.
This commit is contained in:
Simone Bordet 2013-01-10 09:39:56 +01:00
parent a374ac0cc8
commit 34cc0e5d82
1 changed files with 57 additions and 79 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

136
jetty-util/src/main/java/org/eclipse/jetty/util/AttributesMap.java
View File

@ -25,144 +25,122 @@ import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicReference;
/* ------------------------------------------------------------ */
/** AttributesMap.
*
*
*/
public class AttributesMap implements Attributes
{
protected final Map<String,Object> _map;
private final AtomicReference<ConcurrentMap<String, Object>> _map = new AtomicReference<>();
/* ------------------------------------------------------------ */
public AttributesMap()
{
_map=new ConcurrentHashMap<String,Object>();
}
/* ------------------------------------------------------------ */
public AttributesMap(Map<String,Object> map)
{
_map=map;
}
/* ------------------------------------------------------------ */
public AttributesMap(AttributesMap map)
public AttributesMap(AttributesMap attributes)
{
_map=new ConcurrentHashMap<String,Object>(map._map);
ConcurrentMap<String, Object> map = attributes.map();
if (map != null)
_map.set(new ConcurrentHashMap<>(map));
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#removeAttribute(java.lang.String)
*/
private ConcurrentMap<String, Object> map()
{
return _map.get();
}
private ConcurrentMap<String, Object> ensureMap()
{
while (true)
{
ConcurrentMap<String, Object> map = map();
if (map != null)
return map;
map = new ConcurrentHashMap<>();
if (_map.compareAndSet(null, map))
return map;
}
}
@Override
public void removeAttribute(String name)
{
_map.remove(name);
Map<String, Object> map = map();
if (map != null)
map.remove(name);
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#setAttribute(java.lang.String, java.lang.Object)
*/
@Override
public void setAttribute(String name, Object attribute)
{
if (attribute==null)
_map.remove(name);
if (attribute == null)
removeAttribute(name);
else
_map.put(name, attribute);
ensureMap().put(name, attribute);
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#getAttribute(java.lang.String)
*/
@Override
public Object getAttribute(String name)
{
return _map.get(name);
Map<String, Object> map = map();
return map == null ? null : map.get(name);
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#getAttributeNames()
*/
@Override
public Enumeration<String> getAttributeNames()
{
return Collections.enumeration(_map.keySet());
return Collections.enumeration(keySet());
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#getAttributeNames()
*/
public Set<String> getAttributeNameSet()
{
return _map.keySet();
}
/* ------------------------------------------------------------ */
public Set<Map.Entry<String, Object>> getAttributeEntrySet()
{
return _map.entrySet();
Map<String, Object> map = map();
return map == null ? Collections.<Map.Entry<String, Object>>emptySet() : map.entrySet();
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#getAttributeNames()
*/
public static Enumeration<String> getAttributeNamesCopy(Attributes attrs)
{
if (attrs instanceof AttributesMap)
return Collections.enumeration(((AttributesMap)attrs)._map.keySet());
List<String> names = new ArrayList<String>();
return Collections.enumeration(((AttributesMap)attrs).keySet());
List<String> names = new ArrayList<>();
names.addAll(Collections.list(attrs.getAttributeNames()));
return Collections.enumeration(names);
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.jetty.util.Attributes#clear()
*/
@Override
public void clearAttributes()
{
_map.clear();
Map<String, Object> map = map();
if (map != null)
map.clear();
}
/* ------------------------------------------------------------ */
public int size()
{
return _map.size();
Map<String, Object> map = map();
return map == null ? 0 : map.size();
}
/* ------------------------------------------------------------ */
@Override
public String toString()
{
return _map.toString();
Map<String, Object> map = map();
return map == null ? "{}" : map.toString();
}
/* ------------------------------------------------------------ */
public Set<String> keySet()
private Set<String> keySet()
{
return _map.keySet();
Map<String, Object> map = map();
return map == null ? Collections.<String>emptySet() : map.keySet();
}
/* ------------------------------------------------------------ */
public void addAll(Attributes attributes)
{
Enumeration<String> e = attributes.getAttributeNames();
while (e.hasMoreElements())
{
String name=e.nextElement();
setAttribute(name,attributes.getAttribute(name));
String name = e.nextElement();
setAttribute(name, attributes.getAttribute(name));
}
}
}