What does 'synchronized' mean?

In Java, the synchronized keyword is used to provide mutually exclusive access to a shared resource. When a thread tries to execute a synchronized block of code, it will first acquire a lock on the object that the code is synchronized on. If another thread is already executing a synchronized block of code on the same object, the first thread will be blocked until the lock is released.

Here's an example of how you can use the synchronized keyword:

public class Counter {
  private int count = 0;

  public synchronized void increment() {

  public synchronized int getCount() {
    return count;

In this example, the increment and getCount methods are both synchronized on the Counter object. This means that if one thread is executing the increment method, any other threads that try to execute the increment method or the getCount method will be blocked until the first thread releases the lock.

Synchronization is important for ensuring the consistency and integrity of shared data in a multithreaded environment. It can help prevent race conditions and other synchronization issues that can arise when multiple threads access the same data concurrently.

I hope this helps! Let me know if you have any questions.