Thread synchronization

TestSynchronized.java
// Program to Test Synchronized

class MyClass
{
    void myMethod()
    {
        System.out.println("Callin method from MyClass ");
    }
}

class CommonClass
{
    synchronized public void print(String msg)
    {
        System.out.println("Hi");
        
        try
        {
            
            Thread.sleep(1000);
        }   
        catch(Exception e)
        {
            
        }
        System.out.println(msg);
    }
}

class Syn1 extends Thread
{
    CommonClass cc = null;
    public void run()
    {
        
        cc.print("From Syn1");
    }
    
}

class Syn2 extends Thread
{
    CommonClass cc2 = null;
    public void run()
    {
        
        cc2.print("From Syn2");
    }
}

class TestSynchronized
{
    public static void main(String ar[])
    {           
                //creating the object of Synchronized method`s class
        CommonClass c = new CommonClass();
                // Creating the object of extended Thread class
        Syn1 s1 = new Syn1();
        Syn2 s2 = new Syn2();
        
        
                // assigning the CommonClass type reference to Syn1 and Syn3 Class
        s1.cc = c;
        s2.cc2 = c;
                //starting the thread
        s1.start();
        s2.start();
        
        MyClass mc = new MyClass();
        mc.myMethod();
        System.out.println("Main Finished");
    
    }
}
TestSynchronized1.java
// Program to Test Synchronized

class CommonClass
{
    synchronized public void print(String msg)
    {
        System.out.println("Hi");
        
        try
        {
            
            Thread.sleep(1000);
        }   
        catch(Exception e)
        {
            
        }
        System.out.println(msg);
    }
}

class Syn1 extends Thread
{
    CommonClass cc = null;
    public void run()
    {
        
        cc.print("From Syn1");
    }
    
}

class Syn2 extends Thread
{
    CommonClass cc2 = null;
    public void run()
    {
        
        cc2.print("From Syn2");
    }
}

class TestSynchronized1
{
    public static void main(String ar[])
    {           
                //creating the object of Synchronized method`s class
        CommonClass c = new CommonClass();
                // Creating the object of extended Thread class
        Syn1 s1 = new Syn1();
        Syn2 s2 = new Syn2();
        
                // assigning the CommonClass type reference to Syn1 and Syn3 Class
        s1.cc = c;
        s2.cc2 = c;
                //starting the thread
        s1.start();
        s2.start();
        
            // creating another object
        Syn1 ss1 = new Syn1();
        Syn2 ss2 = new Syn2();
        ss1.cc = c;
        ss2.cc2 = c;
        ss1.start();
        ss2.start();
        System.out.println("Main Finished");
        
    }
}