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Question

What will be the output of the program?
Note: Assuming that data must be protected from corruption, what—if anything—can you add to the preceding code to ensure the integrity of data?

public class SyncTest 
{
    public static void main (String [] args) 
    {
        Thread t = new Thread() 
        {
            Foo f = new Foo();
            public void run() 
            {
                f.increase(20);
            }
        };
    t.start();
    }
}
class Foo 
{
    private int data = 23;
    public void increase(int amt) 
    {
        int x = data;
        data = x + amt;
    }
}

a.

Synchronize the run method.

b.

Wrap a synchronize(this) around the call to f.increase().

c.

The existing code will cause a runtime exception.

d.

Synchronize the increase() method

Answer: (d).Synchronize the increase() method

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Q. What will be the output of the program? Note: Assuming that data must be protected from corruption, what—if anything—can you add to the preceding code to ensure the integrity of...

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