I am going to prepare I/o for Java 2 exam. What is need to prepare. 1. Do I need to prepare I/O for exam although it is not in objectives 2. Do I need to remember the hierarcy for streams and character based classes 3. Do i need to remember the constructor for all classes 4. What methods i need to remember if any? 4. What portion of java.net package i need to prepare for the exam.