package db.map;
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import java.util.ArrayList;
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import java.util.Collection;
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import java.util.Collections;
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import java.util.List;
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import java.util.Map;
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import java.util.concurrent.ConcurrentHashMap;
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public class CacheMap<K, V> {
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/**
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* map cache
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*/
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private final Map<K, V> map = Collections.synchronizedMap(new ConcurrentHashMap<K, V>());
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// private final Map<K, V> map = new ConcurrentHashMap<K, V>();
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/**
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* Associates the specified value with the specified key in this map
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*
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* @param key key with which the specified value is to be associated
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* @param value value to be associated with the specified key
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*/
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public void put(K key, V value) {
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map.put(key, value);
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}
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/**
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* Removes the mapping for a key from this map if it is present
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*
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* @param key key whose mapping is to be removed from the map
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*/
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public void remove(K key) {
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map.remove(key);
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}
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/**
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* Returns the number of key-value mappings in this map.
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*
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* @return the size of map
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*/
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public int size() {
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return map.size();
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}
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/**
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* Removes all of the mappings from this map.
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*/
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public void clear() {
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map.clear();
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}
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/**
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* Returns a {@link Collection} view of the values contained in this map.
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*
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* @return a collection view of the values contained in this map
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*/
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public Collection<V> values() {
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return map.values();
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}
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/**
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* Copy a the values contained in this map to a list.
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*
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* @return a list of the values contained in this map
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*/
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public List<V> valuesCopy() {
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Collection<V> values = map.values();
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return new ArrayList<V>(values);
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}
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/**
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* Returns the value to which the specified key is mapped
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*
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* @param key the key whose associated value is to be returned
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* @return the value to which the specified key is mapped, or
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* {@code null} if this map contains no mapping for the key
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*/
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public V get(K key) {
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return map.get(key);
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}
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/**
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* Returns <tt>true</tt> if this map contains a mapping for the specified
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* key.
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* @param key key whose presence in this map is to be tested
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* @return <tt>true</tt> if this map contains a mapping for the specified
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* key
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*/
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public boolean containsKey(K key) {
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return map.containsKey(key);
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}
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}
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