0 new #2 <Class java.lang.Object>
                      //Create an object of type java.lang.Object
                      //and push a reference to it(lock).
3 dup                 //Duplicate the top stack value and push it.
4 invokespecial #3 <Method java.lang.Object()>
                      //Pop the object reference(lock), and invoke
                      //its constructor.
7 astore_1            //Pop the object reference(lock) and store
                      //it at index 1 of the local variable table.