How do you achieve thread safety in a Java program?
Thread safety in Java can be achieved by ensuring that shared data is accessed and modified by only one thread at a time. Some common techniques to achieve thread safety include:
-
Synchronization: Use the
synchronized
keyword to lock methods or blocks of code, ensuring only one thread can access the critical section at a time. -
Locks: Use explicit locks like
ReentrantLock
for more advanced control over thread synchronization (e.g., lock timeouts, try-lock). -
Immutable objects: Make objects immutable so that their state cannot be changed after construction, reducing the need for synchronization.
-
Atomic operations: Use classes from
java.util.concurrent.atomic
(likeAtomicInteger
) for thread-safe operations on single variables. -
Concurrent collections: Use thread-safe collections like
ConcurrentHashMap
,CopyOnWriteArrayList
, etc., which handle synchronization internally.
By applying these strategies, you can ensure that your Java program is thread-safe, preventing data corruption and ensuring reliable concurrent execution.