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public final class ReadWriteLock{
private int readingReaders = 0; // ʵ¼ÊÕýÔÚ¶ÁÈ¡µÄÏß³ÌÊý
private int waitingWriters = 0; // ÕýÔڵȴýдÈëµÄÏß³ÌÊý
private int writingWriters = 0; // ʵ¼ÊÕýÔÚдÈëµÄÏß³ÌÊý
private boolean preferWriter = true; // ÊÇ·ñдÈëÓÅÏÈ
public synchronized void readLock() throws InterruptedException{
while(writingWriters >0 ||(preferWriter && waitingWriters >0)){
wait();
}
readingReaders++;
}
public synchronized void readUnlock() throws InterruptedException{
readingReaders--;
notifyAll();
}
public synchronized void writeLock() throws InterruptedException{
waitingWriters++;
try{
while(readingReaders>0||writingWriters>0){
wait();
}
}finally{
waitingWriters--;
}
writingWriters++;
}
public synchronized void writeUnlock() throws InterruptedException{
writingWriters--;
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