package net.jcip.examples;

import java.util.*;

import java.util.concurrent.locks.*;

/**

* ReadWriteMap

* <p/>

* Wrapping a Map with a read-write lock

*

* @author Brian Goetz and Tim Peierls

*/

public class ReadWriteMap <K,V> {

private final Map<K, V> map;

private final ReadWriteLock lock = new ReentrantReadWriteLock();

private final Lock r = lock.readLock();

private final Lock w = lock.writeLock();

public ReadWriteMap(Map<K, V> map) {

this.map = map;

}

public V put(K key, V value) {

w.lock();

try {

return map.put(key, value);

} finally {

w.unlock();

}

}

public V remove(Object key) {

w.lock();

try {

return map.remove(key);

} finally {

w.unlock();

}

}

public void putAll(Map<? extends K, ? extends V> m) {

w.lock();

try {

map.putAll(m);

} finally {

w.unlock();

}

}

public void clear() {

w.lock();

try {

map.clear();

} finally {

w.unlock();

}

}

public V get(Object key) {

r.lock();

try {

return map.get(key);

} finally {

r.unlock();

}

}

public int size() {

r.lock();

try {

return map.size();

} finally {

r.unlock();

}

}

public boolean isEmpty() {

r.lock();

try {

return map.isEmpty();

} finally {

r.unlock();

}

}

public boolean containsKey(Object key) {

r.lock();

try {

return map.containsKey(key);

} finally {

r.unlock();

}

}

public boolean containsValue(Object value) {

r.lock();

try {

return map.containsValue(value);

} finally {

r.unlock();

}

}

}