/*
* Copyright 1999-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package com.sun.corba.se.impl.orbutil;
import org.omg.CORBA.INTERNAL;
import org.omg.CORBA.CompletionStatus;
import com.sun.corba.se.spi.logging.CORBALogDomains;
import com.sun.corba.se.spi.orb.ORB;
import com.sun.corba.se.impl.logging.ORBUtilSystemException;
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 ORB orb;
private ORBUtilSystemException wrapper;
private CacheTable() {}
public CacheTable(ORB orb, boolean u) {
//System.out.println("using new cache table");
this.orb = orb;
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;
}
}
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