Thread safety in java for static methods

I have the following code

//EDIT :- updated code with @Riaz's answer ( this code should be thread -safe now )

public final class MyClass
{
    private static MyClass2 _class2;
    private MyClass()
    {

    }

    public static synchronized  MyClass CreateMyClass1(String arg0 , ArrayList<MyClass3> class3) throws Exception
    {
        MyClass myClass = new MyClass();        
        _class2 = new Class2(arg0 , class3);
        return myClass;
    }

    public static synchronized  MyClass CreateMyClass2(InputStream arg0 , ArrayList<MyClass3> class3) throws Exception
    {
        MyClass myClass = new MyClass();        
        _class2 = new Class2(arg0 , class3);
        return myClass;
    }

    //EDIT :- added a third method that accesses methods of the _class2 object
    public synchronized   Object getSomething()
    { 
       return MyClass._class2.someMethod();
    }
}

I have read a few posts explaining thread safety for static methods but I have a few questions:

1. 
   

   From what I understand, unless two threads can change the state of a shared mutable object, I don't need to worry about thread safety. (Assuming that I am not leaking the "this" reference.)

   
   

   So when using MyClass, can thread1 call CreateMyClass1 and thread2 call CreateMyClass2 which will mean that the _class2 variable will be changed by thread2 which is what I want to avoid. Will making _class2 as volatile prevent this? If yes, I am not sure how static volatile will be interpreted by the JVM? Will this be enough to make MyClass thread-safe?

   
   


2. 
   

   Does returning an object of the MyClass class in both the static methods cause any violation of thread-safety?