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Introduction to JAVA - Review Questions

Very Basic Questions:
1) JAVA uses classes and objects.  Define classes and objects? What is their relationship?


2) Which of the following are Java reserved words? 
     run, import, default, implement, main, int, Char, exit, extends, catch, if, for, when, do-while, While


Basic Questions:

Which statements are true?
  • The default constructor initialises method variables.
  • The default constructor has the same access as its class.
  • The default constructor invokes the no-arg constructor of the superclass.
  • If a class lacks a no-arg constructor, the compiler always creates a default constructor.
  • The compiler creates a default constructor only when there are no other constructors for the class.

Programming Problems:
1) Create a method called hasDoubleLetters() that returns true if a given word has at least 2 same letters and false if not.

Try to answer them and I will give you feedback!

... more to follow if you want... :-)

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