Reading Key board Input import java.io.*; class Tokenize { public static void main(String[] args) { System.out.println("Enter some numbers and words."); StreamTokenizer st = new StreamTokenizer( new BufferedReader(new InputStreamReader(System.in))); try { // case TT_EOL occurs only if execute st.eolIsSignificant(true); while (st.nextToken() != st.TT_EOF) { switch(st.ttype) { case st.TT_NUMBER: System.out.println("double number=" + st.nval); break; case st.TT_WORD: System.out.println("word=" + st.sval); break; case st.TT_EOL: System.out.println("end of line"); break; default: System.out.println("unrecognized character"); break; } } System.out.println("end of file"); } catch (IOException e) { System.err.println("Tokenize: " + e); } } } /* ............... Example compile and run(s) % javac tokn.java % java Tokenize Enter some numbers and words. 1 2 3 double number=1.0 double number=2.0 double number=3.0 4.0 5.5 6.667 double number=4.0 double number=5.5 double number=6.667 1 abc def,ghi (jkl) !@# double number=1.0 word=abc word=def unrecognized character word=ghi unrecognized character word=jkl unrecognized character unrecognized character unrecognized character unrecognized character ^D end of file ... end of example run(s) */