This class wraps a HashMap and provides methods by which key objects can be associated with "counting" values.
//package org.groovymud.utils;
/* Copyright 2008 Matthew Corby-Eaglen
*
* 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.
*/
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/**
* This class wraps a HashMap and provides methods by which key
* objects can be associated with "counting" values.
*
* useful for timers or other such counting effects
*
* e.g
* countingMap.put(object); // puts (object, 0) into the map
* countingMap.increment(object) // adds 1 to the value of the object (object, 1)
* countingMap.decrement(object) // decreases the value at the object's key reference by 1 (object, 0)
* @author matt
*
*/
public class CountingMap {
Map<Object, Integer> backingMap = new HashMap<Object, Integer>();
public void clear() {
backingMap.clear();
}
public boolean containsKey(Object key) {
return backingMap.containsKey(key);
}
public boolean containsValue(Object value) {
return backingMap.containsValue(value);
}
public Set<?> entrySet() {
return backingMap.entrySet();
}
public boolean equals(Object o) {
return backingMap.equals(o);
}
public Integer get(Object key) {
return backingMap.get(key);
}
public int hashCode() {
return backingMap.hashCode();
}
public boolean isEmpty() {
return backingMap.isEmpty();
}
public Set<?> keySet() {
return backingMap.keySet();
}
public Integer remove(Object key) {
return backingMap.remove(key);
}
public int size() {
return backingMap.size();
}
public Collection<Integer> values() {
return backingMap.values();
}
public Integer put(Object key) {
return put(key, new Integer(0));
}
public Integer put(Object key, Integer value) {
return backingMap.put(key, value);
}
public void putAll(Map<Object, Integer> m) {
backingMap.putAll(m);
}
public void increment(Object key) {
if (!backingMap.containsKey(key)) {
backingMap.put(key, new Integer(0));
} else {
Integer i = backingMap.get(key);
backingMap.put(key, new Integer(i.intValue() + 1));
}
}
public void decrement(Object key) {
if (!backingMap.containsKey(key)) {
backingMap.put(key, new Integer(0));
} else {
Integer i = backingMap.get(key);
backingMap.put(key, new Integer(i.intValue() - 1));
}
}
public Set getKeysAt(int limit) {
Set ret = new HashSet<Object>();
for (Object obj : backingMap.keySet()) {
if (backingMap.get(obj).intValue() == limit) {
ret.add(obj);
}
}
return ret;
}
public Set getKeysAbove(int limit) {
Set ret = new HashSet<Object>();
for (Object obj : backingMap.keySet()) {
if (backingMap.get(obj).intValue() > limit) {
ret.add(obj);
}
}
return ret;
}
public Set getKeysBelow(int limit) {
Set ret = new HashSet<Object>();
for (Object obj : backingMap.keySet()) {
if (backingMap.get(obj).intValue() < limit) {
ret.add(obj);
}
}
return ret;
}
}
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