package com.quadcap.util.collections;
/* Copyright 1999 - 2003 Quadcap Software. All rights reserved.
*
* This software is distributed under the Quadcap Free Software License.
* This software may be used or modified for any purpose, personal or
* commercial. Open Source redistributions are permitted. Commercial
* redistribution of larger works derived from, or works which bundle
* this software requires a "Commercial Redistribution License"; see
* http://www.quadcap.com/purchase.
*
* Redistributions qualify as "Open Source" under one of the following terms:
*
* Redistributions are made at no charge beyond the reasonable cost of
* materials and delivery.
*
* Redistributions are accompanied by a copy of the Source Code or by an
* irrevocable offer to provide a copy of the Source Code for up to three
* years at the cost of materials and delivery. Such redistributions
* must allow further use, modification, and redistribution of the Source
* Code under substantially the same terms as this license.
*
* Redistributions of source code must retain the copyright notices as they
* appear in each source code file, these license terms, and the
* disclaimer/limitation of liability set forth as paragraph 6 below.
*
* Redistributions in binary form must reproduce this Copyright Notice,
* these license terms, and the disclaimer/limitation of liability set
* forth as paragraph 6 below, in the documentation and/or other materials
* provided with the distribution.
*
* The Software is provided on an "AS IS" basis. No warranty is
* provided that the Software is free of defects, or fit for a
* particular purpose.
*
* Limitation of Liability. Quadcap Software shall not be liable
* for any damages suffered by the Licensee or any third party resulting
* from use of the Software.
*/
import java.util.Iterator;
import com.quadcap.util.Debug;
/**
* A map with long values as keys
*
* @author Stan Bailes
*/
public class LongMap {
int size = 0;
Entry[] entries;
Entry freeList;
/**
* Create an empty map with a specified number of buckets.
*/
public LongMap(int initSize) {
initSize |= 1;
while (!isPrime(initSize)) initSize += 2;
entries = new Entry[initSize];
}
/**
* Return the Object with the specified key value
*/
public synchronized final Object get(long key) {
int h = hash(key);
for (Entry entry = entries[h]; entry != null; entry = entry.next) {
if (entry.key == key) return entry.val;
}
return null;
}
/**
* Insert a key, value pair
*/
public synchronized final void put(long key, Object val) {
int h = hash(key);
for (Entry entry = entries[h]; entry != null; entry = entry.next) {
if (entry.key == key) {
entry.val = val;
return;
}
}
Entry entry = getEntry(key, val);
entry.next = entries[h];
entries[h] = entry;
}
/**
* Remove the specified key
*/
public synchronized final void remove(long key) {
int h = hash(key);
Entry prev = null;
Entry entry = entries[h];
while (entry != null) {
Entry next = entry.next;
if (entry.key == key) {
if (prev == null) {
entries[h] = next;
} else {
prev.next = next;
}
freeEntry(entry);
return;
}
prev = entry;
entry = next;
}
}
public String toString() {
StringBuffer sb = new StringBuffer("{");
LongIterator k = keys();
String delim = "";
while (k.hasNext()) {
long v = k.nextLong();
Object d = get(v);
sb.append(delim);
sb.append(v);
sb.append('=');
sb.append(String.valueOf(d));
delim = ",";
}
sb.append("}");
return sb.toString();
}
/**
* Return the number of entries
*/
public final int size() { return size; }
public final int buckets() { return entries.length; }
//-------------------------------------------------------
final Entry getEntry(long key, Object val) {
Entry entry = freeList;
if (entry == null) {
entry = new Entry();
} else {
freeList = entry.next;
}
entry.key = key;
entry.val = val;
size++;
return entry;
}
final void freeEntry(Entry entry) {
size--;
entry.val = null;
entry.next = freeList;
freeList = entry;
}
final boolean isPrime(int x) {
return IntMap.isPrime(x);
}
public LongIterator keys() {
return new LongMapIterator(this);
}
final int hash(long key) {
int h = (int)(key % entries.length);
if (h < 0) {
h = 0 - h;
}
return h;
}
class Entry {
long key;
Object val;
Entry next;
}
public class LongMapIterator implements LongIterator {
LongMap map;
int epos = 0;
Entry entry = null;
Entry last = null;
public LongMapIterator(LongMap map) {
this.map = map;
advance();
}
public boolean hasNext() {
return entry != null;
}
void advance() {
last = entry;
if (entry != null && entry.next != null) {
entry = entry.next;
} else {
entry = null;
}
while (epos < map.entries.length && entry == null) {
entry = map.entries[epos++];
}
}
public Object next() {
Long ret = null;
if (entry != null) {
ret = new Long(entry.key);
advance();
}
return ret;
}
public long nextLong() {
long ret = 0;
if (entry != null) {
ret = entry.key;
advance();
}
return ret;
}
public void remove() {
if (last != null) {
map.remove(last.key);
last = null;
}
}
}
}
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