What strategies are used to prevent deadlock in multithreaded programming?

The following strategies are used to prevent deadlock in multithreaded programming:

1. Avoid cyclic resource acquisition — always acquire locks in the same order in all threads.
2. Use timeouts when attempting to acquire a lock — if the lock is not obtained within a specified time, release already acquired resources and retry.
3. Apply detection and recovery algorithms — periodically check for deadlocks and interrupt or restart threads.
4. Minimize lock holding time — hold locks only for the duration necessary for the critical section.
5. Use higher-level synchronization tools — for example, java.util.concurrent classes, which reduce the risk of deadlock.

Example of ordered lock acquisition:

synchronized(lock1) {
    synchronized(lock2) {
        // critical section
    }
}

Always acquire lock1 before lock2 in all threads to avoid deadlock.