/*
* Copyright 2015 the original author or authors.
* @https://github.com/scouter-project/scouter
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* The initial idea for this class is from "org.apache.commons.lang.IntHashMap";
* http://commons.apache.org/commons-lang-2.6-src.zip
*
*/
package scouter.util;
import java.util.Enumeration;
import java.util.NoSuchElementException;
/**
* @author Paul Kim (sjkim@whatap.io)
*/
public class LongKeyLinkedMap<V> {
private static final int DEFAULT_CAPACITY = 101;
private static final float DEFAULT_LOAD_FACTOR = 0.75f;
private LongKeyLinkedEntry<V> table[];
private LongKeyLinkedEntry<V> header;
private int count;
private int threshold;
private float loadFactor;
@SuppressWarnings("unchecked")
public LongKeyLinkedMap(int initCapacity, float loadFactor) {
if (initCapacity < 0)
throw new RuntimeException("Capacity Error: " + initCapacity);
if (loadFactor <= 0)
throw new RuntimeException("Load Count Error: " + loadFactor);
if (initCapacity == 0)
initCapacity = 1;
this.loadFactor = loadFactor;
this.table = new LongKeyLinkedEntry[initCapacity];
this.header = new LongKeyLinkedEntry<V>(0, null, null);
this.header.link_next = header.link_prev = header;
threshold = (int) (initCapacity * loadFactor);
}
public LongKeyLinkedMap() {
this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR);
}
public int size() {
return count;
}
public long[] keyArray() {
long[] _keys = new long[this.size()];
LongEnumer en = this.keys();
for (int i = 0; i < _keys.length; i++)
_keys[i] = en.nextLong();
return _keys;
}
public synchronized LongEnumer keys() {
return new Enumer(TYPE.KEYS);
}
public synchronized Enumeration<V> values() {
return new Enumer<V>(TYPE.VALUES);
}
public synchronized Enumeration<LongKeyLinkedEntry<V>> entries() {
return new Enumer<LongKeyLinkedEntry>(TYPE.ENTRIES);
}
public synchronized boolean containsValue(Object value) {
if (value == null || size() == 0) {
return false;
}
LongKeyLinkedEntry tab[] = table;
int i = tab.length;
while (i-- > 0) {
for (LongKeyLinkedEntry e = tab[i]; e != null; e = e.next) {
if (CompareUtil.equals(e.value, value)) {
return true;
}
}
}
return false;
}
public synchronized boolean containsKey(long key) {
if (this.size() == 0)
return false;
LongKeyLinkedEntry tab[] = table;
int index = hash(key) % tab.length;
for (LongKeyLinkedEntry e = tab[index]; e != null; e = e.next) {
if (CompareUtil.equals(e.key, key)) {
return true;
}
}
return false;
}
public synchronized V get(long key) {
if (this.size() == 0)
return null;
LongKeyLinkedEntry<V> tab[] = table;
int index = hash(key) % tab.length;
for (LongKeyLinkedEntry<V> e = tab[index]; e != null; e = e.next) {
if (CompareUtil.equals(e.key, key)) {
return e.value;
}
}
return null;
}
public V intern(long key) {
return _intern(key, MODE.LAST);
}
private synchronized V _intern(long key, MODE m) {
LongKeyLinkedEntry<V> tab[] = table;
int index = hash(key) % tab.length;
for (LongKeyLinkedEntry<V> e = tab[index]; e != null; e = e.next) {
if (CompareUtil.equals(e.key, key)) {
return e.value;
}
}
V value = create(key);
if (value == null)
return null;
if (max > 0) {
switch (m) {
case FORCE_FIRST:
case FIRST:
while (count >= max) {
//removeLast();
long k = header.link_prev.key;
V v = remove(k);
overflowed(k, v);
}
break;
case FORCE_LAST:
case LAST:
while (count >= max) {
//removeFirst();
long k = header.link_next.key;
V v = remove(k);
overflowed(k, v);
}
break;
}
}
if (count >= threshold) {
rehash();
tab = table;
index = hash(key) % tab.length;
}
LongKeyLinkedEntry e = new LongKeyLinkedEntry(key, value, tab[index]);
tab[index] = e;
switch (m) {
case FORCE_FIRST:
case FIRST:
chain(header, header.link_next, e);
break;
case FORCE_LAST:
case LAST:
chain(header.link_prev, header, e);
break;
}
count++;
return value;
}
protected void overflowed(long key, V value){
}
protected V create(long key) {
throw new RuntimeException("not implemented create()");
}
public synchronized long getFirstKey() {
if (this.size() == 0)
return 0;
return this.header.link_next.key;
}
public synchronized long getLastKey() {
if (this.size() == 0)
return 0;
return this.header.link_prev.key;
}
public synchronized V getFirstValue() {
if (this.size() == 0)
return null;
return this.header.link_next.value;
}
public synchronized V getLastValue() {
if (this.size() == 0)
return null;
return this.header.link_prev.value;
}
private int hash(long key) {
return (int) (key ^ (key >>> 32)) & Integer.MAX_VALUE;
}
protected void rehash() {
int oldCapacity = table.length;
LongKeyLinkedEntry oldMap[] = table;
int newCapacity = oldCapacity * 2 + 1;
LongKeyLinkedEntry newMap[] = new LongKeyLinkedEntry[newCapacity];
threshold = (int) (newCapacity * loadFactor);
table = newMap;
for (int i = oldCapacity; i-- > 0;) {
LongKeyLinkedEntry old = oldMap[i];
while (old != null) {
LongKeyLinkedEntry e = old;
old = old.next;
long key = e.key;
int index = hash(key) % newCapacity;
e.next = newMap[index];
newMap[index] = e;
}
}
}
private int max;
public LongKeyLinkedMap<V> setMax(int max) {
this.max = max;
return this;
}
private static enum MODE {
FORCE_FIRST, FORCE_LAST, FIRST, LAST
};
public V put(long key, V value) {
return _put(key, value, MODE.LAST);
}
public V putLast(long key, V value) {
return _put(key, value, MODE.FORCE_LAST);
}
public V putFirst(long key, V value) {
return _put(key, value, MODE.FORCE_FIRST);
}
private synchronized V _put(long key, V value, MODE m) {
LongKeyLinkedEntry tab[] = table;
int index = hash(key) % tab.length;
for (LongKeyLinkedEntry<V> e = tab[index]; e != null; e = e.next) {
if (CompareUtil.equals(e.key, key)) {
V old = e.value;
e.value = value;
switch (m) {
case FORCE_FIRST:
if (header.link_next != e) {
unchain(e);
chain(header, header.link_next, e);
}
break;
case FORCE_LAST:
if (header.link_prev != e) {
unchain(e);
chain(header.link_prev, header, e);
}
break;
}
return old;
}
}
if (max > 0) {
switch (m) {
case FORCE_FIRST:
case FIRST:
while (count >= max) {
//removeLast();
long k = header.link_prev.key;
V v = remove(k);
overflowed(k, v);
}
break;
case FORCE_LAST:
case LAST:
while (count >= max) {
//removeFirst();
long k = header.link_next.key;
V v = remove(k);
overflowed(k, v);
}
break;
}
}
if (count >= threshold) {
rehash();
tab = table;
index = hash(key) % tab.length;
}
LongKeyLinkedEntry e = new LongKeyLinkedEntry(key, value, tab[index]);
tab[index] = e;
switch (m) {
case FORCE_FIRST:
case FIRST:
chain(header, header.link_next, e);
break;
case FORCE_LAST:
case LAST:
chain(header.link_prev, header, e);
break;
}
count++;
return null;
}
public synchronized V remove(long key) {
LongKeyLinkedEntry tab[] = table;
int index = hash(key) % tab.length;
for (LongKeyLinkedEntry<V> e = tab[index], prev = null; e != null; prev = e, e = e.next) {
if (CompareUtil.equals(e.key, key)) {
if (prev != null) {
prev.next = e.next;
} else {
tab[index] = e.next;
}
count--;
V oldValue = e.value;
e.value = null;
//
unchain(e);
return oldValue;
}
}
return null;
}
public synchronized V removeFirst() {
if (isEmpty())
return null;
return remove(header.link_next.key);
}
public synchronized V removeLast() {
if (isEmpty())
return null;
return remove(header.link_prev.key);
}
public boolean isEmpty() {
return size() == 0;
}
public synchronized void clear() {
LongKeyLinkedEntry tab[] = table;
for (int index = tab.length; --index >= 0;)
tab[index] = null;
this.header.link_next = header.link_prev = header;
count = 0;
}
public String toString() {
StringBuffer buf = new StringBuffer();
Enumeration it = entries();
buf.append("{");
for (int i = 0; it.hasMoreElements(); i++) {
LongKeyLinkedEntry e = (LongKeyLinkedEntry) (it.nextElement());
if (i > 0)
buf.append(", ");
buf.append(e.getKey() + "=" + e.getValue());
}
buf.append("}");
return buf.toString();
}
public String toFormatString() {
StringBuffer buf = new StringBuffer();
Enumeration it = entries();
buf.append("{\n");
while (it.hasMoreElements()) {
LongKeyLinkedEntry e = (LongKeyLinkedEntry) it.nextElement();
buf.append("\t").append(e.getKey() + "=" + e.getValue()).append("\n");
}
buf.append("}");
return buf.toString();
}
private enum TYPE {
KEYS, VALUES, ENTRIES
}
private class Enumer<V> implements Enumeration, LongEnumer {
TYPE type;
LongKeyLinkedEntry entry = LongKeyLinkedMap.this.header.link_next;
Enumer(TYPE type) {
this.type = type;
}
public boolean hasMoreElements() {
return header != entry;
}
public V nextElement() {
if (entry != null) {
LongKeyLinkedEntry e = entry;
entry = e.link_next;
switch (type) {
case KEYS:
return (V) new Long(e.key);
case VALUES:
return (V) e.value;
default:
return (V) e;
}
}
throw new NoSuchElementException("Enumerator");
}
public long nextLong() {
if (entry != null) {
LongKeyLinkedEntry e = entry;
entry = e.link_next;
return e.key;
}
throw new NoSuchElementException("Enumer");
}
}
private void chain(LongKeyLinkedEntry link_prev, LongKeyLinkedEntry link_next, LongKeyLinkedEntry e) {
e.link_prev = link_prev;
e.link_next = link_next;
link_prev.link_next = e;
link_next.link_prev = e;
}
private void unchain(LongKeyLinkedEntry e) {
e.link_prev.link_next = e.link_next;
e.link_next.link_prev = e.link_prev;
e.link_prev = null;
e.link_next = null;
}
public static class LongKeyLinkedEntry<V> {
long key;
V value;
LongKeyLinkedEntry<V> next;
LongKeyLinkedEntry<V> link_next, link_prev;
protected LongKeyLinkedEntry(long key, V value, LongKeyLinkedEntry<V> next) {
this.key = key;
this.value = value;
this.next = next;
}
protected Object clone() {
return new LongKeyLinkedEntry(key, value, (next == null ? null : (LongKeyLinkedEntry) next.clone()));
}
public long getKey() {
return key;
}
public V getValue() {
return value;
}
public V setValue(V value) {
if (value == null)
throw new NullPointerException();
V oldValue = this.value;
this.value = value;
return oldValue;
}
public boolean equals(Object o) {
if (!(o instanceof LongKeyLinkedEntry))
return false;
LongKeyLinkedEntry e = (LongKeyLinkedEntry) o;
return CompareUtil.equals(e.key, key) && CompareUtil.equals(e.value, value);
}
public int hashCode() {
return (int) (key ^ (key >>> 32)) ^ (value == null ? 0 : value.hashCode());
}
public String toString() {
return key + "=" + value;
}
}
public static void main(String[] args) {
LongKeyLinkedMap m = new LongKeyLinkedMap().setMax(2);
m.putLast(10, 10);
m.putLast(20, 20);
m.putFirst(30, 30);
// m.removeFirst();
System.out.println(m);
m = new LongKeyLinkedMap().setMax(2);
m.putFirst(10, 10);
m.putFirst(20, 20);
m.putFirst(30, 30);
// m.removeLast();
System.out.println(m);
}
private static void print(Object e) {
System.out.println(e);
}
}