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4.4 TOKENS
                 A Java program is composed of individual units called tokens. Tokens are the smallest elements of a Java program
                 that have meaning to the Java compiler and serve as the fundamental building blocks of the program.

                 Every Java expression and statement is constructed using tokens. During compilation, the Java compiler reads the
                 source code, identifies each token, and then translates these tokens into Java bytecode, which the Java Virtual
                 Machine  (JVM) executes based  on  the program's logic.Java tokens help  the compiler  detect syntax errors by
                 allowing it to check for invalid or misplaced tokens, making them essential for ensuring code correctness.


                  Program 11     Write a program to demonstrate the use of Token.

                   1  class eg_of_token
                   2  {

                   3      public static void main()

                   4      {
                   5          System.out.println("This is a program to explain \"Token\".");
                   6      }

                   7  }
                 Here, This source code includes Java tokens such as class, token, {, public, static, void, main, (, ), {, System, out,
                 println, (,“,This is a program to explain \"Token\".,”,},}.
                 You will get the following output:











                                                             Definition


                         Java token is the atomic part of a java program that has a meaning for the compiler and is used
                         to execute the program efficiently.



                 There are various types of Tokens that are used by the Java Compiler: Keywords, Identifiers, Literals, Operators and
                 Special Symbols such as Punctuators, Separators.

                 4.4.1 Keywords
                 Keywords are pre-defined words that are reserved by the Java compiler for a specific purpose and used only in a
                 limited, specific manner. It cannot be used as a variable name as it will assign a new meaning to the keyword. This
                 will be treated as an error by the compiler. They are also known as reserved words. List of keywords used in java
                 given below.

                 Assert               double              implements          protected           throw
                 boolean              else                import              public              throws

                 break                enum                instanceof          return              transient



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