Page 58 - Trackpad_ipro 4.1_Class8
P. 58
Examples of some valid identifier names are Employee123, mygood_book, _address93, FirstName,
age, etc.
Examples of some invalid identifier names are 1_Name, @Address, 1234, –Age, etc.
Keywords
Keywords are reserved words that cannot be used as identifiers because they have a special
meaning for the Java compiler. Some of the Java keywords are given below:
Java Keywords
abstract class final interface static
assert const float long switch
boolean continue for new this
break default if private throw
byte do implements protected throws
case double import public try
catch else instanceof return void
char extends int short while
Although reserved as a keyword in Java, const is not used and has no function.
Additionally, there are three more reserved words in Java: true, false, and null. Technically, these
are literal values rather than keywords. However, they cannot be used as identifiers and have
specific meanings for the Java compiler.
Data Types
A data type defines the size and type of value that a variable can store. Java provides two types
of data types: primitive and non-primitive.
Primitive Data Types
Java provides eight basic data types, as shown in the following table:
Size
Data Type Minimum Value Maximum Value
(in bits)
byte 8 -128 127
short 16 –32768 32767
If Excel was a magical library, how would you sort books and filter books you
had read?
56 iPro (Ver. 4.1)-VIII

