悲观锁，乐观锁，读写锁，行锁，表锁，自旋锁，死锁，分布式锁，线程同步锁，公平锁，非公平锁分别是什么

sql复制代码-- 悲观锁示例
BEGIN;
SELECT * FROM products WHERE product_id = 1 FOR UPDATE;
-- 进行相关操作...
COMMIT;

java复制代码public boolean updateProduct(Product product) {
    String sql = "UPDATE products SET stock = ?, version = ? WHERE product_id = ? AND version = ?";
    int result = jdbcTemplate.update(sql, product.getStock(), product.getVersion() + 1, product.getProductId(), product.getVersion());
    return result == 1;
}

java复制代码ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();
Lock readLock = readWriteLock.readLock();
Lock writeLock = readWriteLock.writeLock();

public void readData() {
    readLock.lock();
    try {
        // 读取数据
    } finally {
        readLock.unlock();
    }
}

public void writeData() {
    writeLock.lock();
    try {
        // 写入数据
    } finally {
        writeLock.unlock();
    }
}

java复制代码public class SpinLock {
    private AtomicReference<Thread> owner = new AtomicReference<>();

    public void lock() {
        Thread currentThread = Thread.currentThread();
        while (!owner.compareAndSet(null, currentThread)) {
            // 自旋
        }
    }

    public void unlock() {
        Thread currentThread = Thread.currentThread();
        owner.compareAndSet(currentThread, null);
    }
}

java复制代码public boolean acquireLock(Jedis jedis, String lockKey, String requestId, int expireTime) {
    String result = jedis.set(lockKey, requestId, "NX", "PX", expireTime);
    return "OK".equals(result);
}

public boolean releaseLock(Jedis jedis, String lockKey, String requestId) {
    String script = "if redis.call('get', KEYS[1]) == ARGV[1] then " +
                    "return redis.call('del', KEYS[1]) else return 0 end";
    Object result = jedis.eval(script, Collections.singletonList(lockKey), Collections.singletonList(requestId));
    return "1".equals(result);
}

java复制代码public synchronized void synchronizedMethod() {
    // 同步代码块
}

public void reentrantLockMethod() {
    ReentrantLock lock = new ReentrantLock();
    lock.lock();
    try {
        // 同步代码块
    } finally {
        lock.unlock();
    }
}

java复制代码ReentrantLock fairLock = new ReentrantLock(true);  // 公平锁
ReentrantLock nonFairLock = new ReentrantLock();   // 非公平锁，默认

public void fairLockMethod() {
    fairLock.lock();
    try {
        // 同步代码块
    } finally {
        fairLock.unlock();
    }
}