Explain Java Tokens?
https://www.computersprofessor.com/2016/05/explain-java-tokens.html
A Java program is basically a
collection of classes.
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A class is
defined by a set of declaration statements and methods containing executable
statements.
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Most
statements contain expressions which describe the actions carried out on
data.
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Smallest
individual units in a program are known as tokens.
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In simple,
a Java program is a collection of tokens, comments and white space.
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Java
language includes five types of tokens:
1) Reserved keywords
2) Identifiers
3)
Literals
4)
Operators
5)
Separators
Keywords :
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Keywords
are an essential part of a language definition.
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Java
language has reserved words as keyword.
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Keywords
have specific meaning in Java we cannot use them as names for variables,
classes, methods and so … on.
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All
keywords are to be written in lower case letters.
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Java is
case sensitive.
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Identifies :
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Identifiers
are programmer designed tokens.
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They are
used for naming classes, methods, variable objects, labels, packages and
interfaces in a program.
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Java
identifiers follow the following rules.
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1) They can
have alphabets, digits & underscore & dollar sign characters.
2) They
must not begin with a digit.
3) Upper
case & lower case letters are distinct.
4) They can
be of any length.
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Literal :
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Literals in Java are a sequence of
character (digits, letters and other character) that represent constant
values to be stored in variables.
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Integer
literals
Floating point literals
Character literals
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String
literals
Boolean literals
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Operators :
An operator is a symbol that takes
one or more argyments and operates on them to produce a result.
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Separators :
Separators are symbols used to
indicate where groups of code are divided and arranged.
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Parentheses ( ) : Used to enclosed parameters in
method definition.
Braces { }:
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1.
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Define a
block of code for classes methods and local scope.
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2.
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Automatically
initialize values to array.
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Brackets [ ] : Used to declare array types.
Semicolon (;) : Used to separate statement.
Comma (,) : Used to separate identifiers in a variable deceleration.
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