What is thread synchronization? Explain the concept of multithread in java with suitable example.

 Thread synchronization is the process of coordinating the execution of threads to ensure that they do not interfere with each other and access shared resources in a predictable and consistent manner. In other words, thread synchronization is about managing access to shared resources so that multiple threads can access them safely and without conflicting with each other.

In Java, multithreading refers to the ability of a program to run multiple threads of execution concurrently. A thread is a lightweight process that can execute independently of other threads within the same program. By using multiple threads, a program can perform multiple tasks at the same time, improving performance and responsiveness.

Here's an example of multithreading in Java:

public class Counter implements Runnable {
    private int count;
    public void run() {
        for (int i = 1; i <= 5; i++) {
            increment();
            System.out.println(Thread.currentThread().getName() + ": " + count);
        }
    }
    public synchronized void increment() {
        count++;
    }
    public static void main(String[] args) {
        Counter c = new Counter();
        Thread t1 = new Thread(c);
        Thread t2 = new Thread(c);
        t1.setName("Thread 1");
        t2.setName("Thread 2");
        t1.start();
        t2.start();
    }
}

In this example, we create a class called Counter that implements the Runnable interface. The run method of the Counter class contains a loop that increments the count variable and prints its value to the console. The increment method of the Counter class is synchronized to ensure that only one thread can access it at a time.

In the main method, we create two threads t1 and t2 and pass an instance of the Counter class as a parameter to their constructors. We also set the names of the threads to "Thread 1" and "Thread 2", respectively. Finally, we start the threads using the start method.

When we run this program, we should see output like the following:

Thread 1: 1
Thread 1: 2
Thread 1: 3
Thread 1: 4
Thread 1: 5
Thread 2: 6
Thread 2: 7
Thread 2: 8
Thread 2: 9
Thread 2: 10

As you can see, the two threads are running concurrently and incrementing the count variable. However, because the increment method is synchronized, they are not interfering with each other and the output is predictable and consistent.