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Keep type boolean
As you saw earlier , the authors of the exam have included type boolean in the exam.
In this case, there was no opportunity to exclude other similar types. The boolean type is one of a kind and you will need to know how to use it when taking the exam.
As you saw earlier , the authors of the exam elected not to include type char in the exam, and they gave several reasons why.
However, just in case you are curious about this type, I will provide some information about it in the following paragraphs.
The character type char
Computers deal only in numeric values. They don't know how to deal directly with the letters of the alphabet and punctuation characters.
The purpose of the character type char is to make it possible to represent the letters of the alphabet, the punctuation characters, and the numeric characters internally in the computer. This is accomplished by assigning a numeric value to each character, much as you may have done to create secret codes when you were a child. (For example, in Java an upper-case A character is represented by the numeric value 65, whereas the upper-case B is represented by the numeric value 66.)
A single character type
Java supports a single character type named char . The char type uses a standard character representation known as Unicode to represent up to 65,535 different characters.
Why so many characters?
The reason for the large number of possible characters is to make it possible to represent the characters making up the alphabets of many different countries and many different languages.
Representing a character symbolically
Although each character is represented internally by a numeric value, as long as the characters that you use in your program appear on your keyboard, you usually don't have a need to know the numeric values associated with the different characters.
In Java, you usually represent a character to the program by surrounding it with apostrophes as follows: 'A'.
The Java programming tools know how to cross-reference that specific character symbol against the Unicode table to obtain the corresponding numeric value. (A discussion of the use of the char type to represent characters that don't appear on your keyboard is beyond the scope of this lesson.)
This section contains a variety of miscellaneous materials.
Financial : Although the Connexions site makes it possible for you to download a PDFfile for this module at no charge, and also makes it possible for you to purchase a pre-printed version of the PDF file, you should be aware thatsome of the HTML elements in this module may not translate well into PDF.
I also want you to know that, I receive no financial compensation from the Connexions website even if you purchase the PDF version of the module.
In the past, unknown individuals have copied my modules from cnx.org, converted them to Kindle books, and placed them for sale on Amazon.comshowing me as the author. I neither receive compensation for those sales nor do I know who does receive compensation. If you purchase such a book, pleasebe aware that it is a copy of a module that is freely available on cnx.org and that it was made and published without my prior knowledge.
Affiliation : I am a professor of Computer Information Technology at Austin Community College in Austin, TX, and have noaffiliation with the College Board .
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