JAVA EE: Java Tutorial : Java IO (Java StreamTokenizer

Wednesday, 19 October 2016

Java Tutorial : Java IO (Java StreamTokenizer - How to tokenize file content)

Click here to watch in Youtube :
https://www.youtube.com/watch?v=x7LPhfcnTKg&list=UUhwKlOVR041tngjerWxVccw

myfile.txt

Hello, How are you peter?
Shall we go to India. 2+2=4

StreamTokenizerDemo.java

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.StreamTokenizer;

public class StreamTokenizerDemo
{

    public static void main(String[] args) throws IOException
    {
        FileReader fileReader = null;
        BufferedReader bufferedReader = null;
        try
        {
            fileReader = new FileReader("myfile.txt");
            bufferedReader = new BufferedReader(fileReader);
            StreamTokenizer st = new StreamTokenizer(bufferedReader);

            // print the stream tokens
            boolean eof = false;
            do
            {
                /*
                 * Parses the next token from the input
                 * stream of this tokenizer. The type of the
                 * next token is returned in the ttype
                 * field. Additional information about the
                 * token may be in the nval field or the
                 * sval field of this tokenizer.
                 *
                 * Typical clients of this class first set
                 * up the syntax tables and then sit in a
                 * loop calling nextToken to parse
                 * successive tokens until TT_EOF is
                 * returned.
                 */
                int token = st.nextToken();
                switch (token)
                {
                case StreamTokenizer.TT_EOF:
                    System.out.println("End of File encountered.");
                    eof = true;
                    break;
                case StreamTokenizer.TT_EOL:
                    System.out.println("End of Line encountered.");
                    System.out.println("Line Number:" + st.lineno());
                    break;
                case StreamTokenizer.TT_WORD:
                    System.out.println("Word: " + st.sval);
                    break;
                case StreamTokenizer.TT_NUMBER:
                    System.out.println("Number: " + st.nval);
                    break;
                default:
                    System.out.println((char) token + " encountered.");
                    if (token == '!')
                    {
                        eof = true;
                    }
                }
            }
            while (!eof);
        }
        finally
        {
            if (bufferedReader != null)
            {
                bufferedReader.close();
            }
        }

    }

}

Output

Word: Hello
, encountered.
Word: How
Word: are
Word: you
Word: peter
? encountered.
Word: Shall
Word: we
Word: go
Word: to
Word: India.
Number: 2.0
+ encountered.
Number: 2.0
= encountered.
Number: 4.0
End of File encountered.