Uğur Dönmez

import java.util.Map;
import java.util.TreeMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import javax.xml.crypto.Data;

public class ReadWriteMap {
    final Map m = new TreeMap();
    final ReentrantReadWriteLock rw1 = new ReentrantReadWriteLock();
    final Lock r = rw1.readLock();
    final Lock w = rw1.writeLock();

    public Data get(String key) {
        r.lock();
        try {
            return m.get(key);
        } finally  {
            r.unlock();
        }
    }

    public Data put(String key,Data value) {
        w.lock();
        try {
            return m.put(key, value);
        }
        finally {
            w.unlock();
        }
    }

    public void clear() {
        w.lock();
        try {
            m.clear();
        }
        finally {
            w.unlock();
        }
    }
}