/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package org.jboss.com.sun.corba.se.impl.orbutil;
import org.jboss.com.sun.corba.se.impl.logging.ORBUtilSystemException;
import org.jboss.com.sun.corba.se.spi.logging.CORBALogDomains;
import org.jboss.com.sun.corba.se.spi.orb.ORB;
public class CacheTable
{
class Entry
{
java.lang.Object key;
int val;
Entry next; // this chains the collision list of table "map"
Entry rnext; // this chains the collision list of table "rmap"
public Entry(java.lang.Object k, int v)
{
key = k;
val = v;
next = null;
rnext = null;
}
}
private boolean noReverseMap;
// size must be power of 2
static final int INITIAL_SIZE = 16;
static final int MAX_SIZE = 1 << 30;
int size;
int entryCount;
private Entry[] map;
private Entry[] rmap;
private ORBUtilSystemException wrapper;
@SuppressWarnings("unused")
private CacheTable()
{
}
public CacheTable(ORB orb, boolean u)
{
// System.out.println("using new cache table");
wrapper = ORBUtilSystemException.get(orb, CORBALogDomains.RPC_ENCODING);
noReverseMap = u;
size = INITIAL_SIZE;
entryCount = 0;
initTables();
}
private void initTables()
{
map = new Entry[size];
rmap = noReverseMap ? null : new Entry[size];
}
private void grow()
{
if (size == MAX_SIZE)
return;
Entry[] oldMap = map;
int oldSize = size;
size <<= 1;
initTables();
// now rehash the entries into the new table
for (int i = 0; i < oldSize; i++)
{
for (Entry e = oldMap[i]; e != null; e = e.next)
put_table(e.key, e.val);
}
}
private int moduloTableSize(int h)
{
// these are the "supplemental hash function" copied from
// java.util.HashMap, supposed to be "critical"
h += ~(h << 9);
h ^= (h >>> 14);
h += (h << 4);
h ^= (h >>> 10);
return h & (size - 1);
}
private int hash(java.lang.Object key)
{
return moduloTableSize(System.identityHashCode(key));
}
private int hash(int val)
{
return moduloTableSize(val);
}
public final void put(java.lang.Object key, int val)
{
if (put_table(key, val))
{
entryCount++;
if (entryCount > size * 3 / 4)
grow();
}
}
private boolean put_table(java.lang.Object key, int val)
{
int index = hash(key);
for (Entry e = map[index]; e != null; e = e.next)
{
if (e.key == key)
{
if (e.val != val)
{
throw wrapper.duplicateIndirectionOffset();
}
// if we get here we are trying to put in the same key/val pair this is a no-op, so we just return
return false;
}
}
// this means the key is not present in our table then it shouldnt be present in our reverse table either
Entry newEntry = new Entry(key, val);
newEntry.next = map[index];
map[index] = newEntry;
if (!noReverseMap)
{
int rindex = hash(val);
newEntry.rnext = rmap[rindex];
rmap[rindex] = newEntry;
}
return true;
}
public final boolean containsKey(java.lang.Object key)
{
return (getVal(key) != -1);
}
public final int getVal(java.lang.Object key)
{
int index = hash(key);
for (Entry e = map[index]; e != null; e = e.next)
{
if (e.key == key)
return e.val;
}
return -1;
}
public final boolean containsVal(int val)
{
return (getKey(val) != null);
}
public final boolean containsOrderedVal(int val)
{
return containsVal(val);
}
public final java.lang.Object getKey(int val)
{
int index = hash(val);
for (Entry e = rmap[index]; e != null; e = e.rnext)
{
if (e.val == val)
return e.key;
}
return null;
}
public void done()
{
map = null;
rmap = null;
}
}