Line2 doesn't throw an exception. From the Oracle javadocs:
The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
That means your Line2 just prints what objA.toString() returns, which is
since exception.RuntimeExceptionTest is your class name.