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You will get the following output:








                     3.4 TOKENS
                 A Java program may contain thousands of lines of code. Each of these codes is written using Java tokens. A token is
                 considered the smallest individual element in a Java program that has a meaning. Tokens are also known as the building
                 blocks of a Java program.
                 Tokens are something equivalent to the cells of a living organism
                 which are the basic building blocks of all living things. Similarly,       Definition
                 tokens are the smallest elements that can be identified by the Java
                 compiler.  All  Java  expressions  and  statements  are  constructed   Tokens  are  the smallest units of  code  that  the
                 by tokens. The compiler reads the source code when we try to   Java  compiler recognizes  as meaningful and
                 compile  a  program,  and  then  extracts  individual  Java  tokens   syntactically correct.
                 and  translates  them  into  Java  byte  codes  which  are  executed
                 according to their meaning. They are also useful for compilers to detect errors.

                 There are various types of tokens that are used by the Java compiler which are as follows:
                 •  Keywords                            •    Identifiers                     •    Literals
                 •  Operators                           •    Punctuators
                 Let us learn about these in detail.

                 3.4.1 Keywords
                 Keywords are reserved words that have pre-defined meaning in the Java compiler for a specific purpose. We cannot
                 use Java keywords as variable names. If you try to use keywords as variable names, then the Java compiler will give an
                 error message. A list of keywords used in Java is given below:
                                   abstract      do            if           private       this
                                   assert        double        implements   protected     throw
                                   boolean       else          import       public        throws
                                   break         enum          instanceof   return        transient
                                   byte          extends       int          short         true
                                   case          false         interface    static        try
                                   catch         final         long         strictfp      void
                                   char          finally       native       super         volatile
                                   class         float         new          switch        while
                                   const         for           null         synchronized continue
                                   default       goto          package


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