Wrap-Up

Answers to Self Review Exercises

28.1	a) Streams. b) Standard input. c) Standard output. d) printf. e) d. f) o, x or X. g) e or E. h) 6. i) s or S, c or C. j) t, T. k) - (minus). l) + (plus). m) 2$. n) Formatter.
28.2	Error: Conversion character c expects an argument of primitive type char. Correction: To print the character 'c', change "c" to 'c'. Error: Trying to print the literal character % without using the format specifier %%. Correction: Use %% to print a literal % character. Error: Argument index does not start with 0, e.g., the first argument is 1$. Correction: To print the third argument use 3$. Error: Trying to print the literal character " without using the " escape sequence. Correction: Replace each quote in the inner set of quotes with ". Error: The format string is not enclosed in double quotes. Correction: Enclose %d %d in double quotes. Error: The string to be printed is enclosed in single quotes. Correction: Use double quotes instead of single quotes to represent a string.
28.3	System.out.printf( "%10d ", 1234 ); System.out.printf( "%+.3e ", 123.456789 ); System.out.printf( "%#o ", 100 ); System.out.printf( "%tD ", calendar ); System.out.printf( "%1$tH:%1$tM:%1$tS ", calendar ); System.out.printf( "%+20.3f ", 3.333333 );

Exercises

28.4	Write statement(s) for each of the following: Print integer 40000 right justified in a 15-digit field. Print 200 with and without a sign. Print 100 in hexadecimal form preceded by 0x. Print 1.234 with three digits of precision in a nine-digit field with preceding zeros.
28.5	Show what is printed by each of the following statements. If a statement is incorrect, indicate why. System.out.printf( "%-10d ", 10000 ); System.out.printf( "%c ", "This is a string" ); System.out.printf( "%8.3f ", 1024.987654 ); System.out.printf( "%#o %#X ", 17, 17 ); System.out.printf( "% d %+d ", 1000000, 1000000 ); System.out.printf( "%10.2e ", 444.93738 ); System.out.printf( "%d ", 10.987 );
28.6	Find the error(s) in each of the following program segments. Show the corrected statement. System.out.printf( "%s ", 'Happy Birthday' ); System.out.printf( "%c ", 'Hello' ); System.out.printf( "%c ", "This is a string" ); The following statement should print "Bon Voyage" with the double quotes: System.out.printf( ""%s"", "Bon Voyage" ); The following statement should print "Today is Friday": System.out.printf( "Today is %s ", "Monday", "Friday" ); System.out.printf( 'Enter your name: ' ); System.out.printf( %f, 123.456 ); The following statement should print the current time in the format "hh:mm:ss": Calendar dateTime = Calendar.getInstance(); System.out.printf( "%1$tk:1$%tl:%1$tS ", dateTime );
28.7	(Printing Dates and Times) Write a program that prints dates and times in the following forms: GMT-05:00 04/30/04 09:55:09 AM GMT-05:00 April 30 2004 09:55:09 2004-04-30 day-of-the-month:30 2004-04-30 day-of-the-year:121 Fri Apr 30 09:55:09 GMT-05:00 2004   [ Note: Depending on your location, you may get the time zone other than GMT-05:00.]
28.8	Write a program to test the results of printing the integer value 12345 and the floating-point value 1.2345 in various size fields.
28.9	(Rounding Numbers) Write a program that prints the value 100.453627 rounded to the nearest digit, tenth, hundredth, thousandth and ten thousandth.
28.10	Write a program that inputs a word from the keyboard and determines the length of the word. Print the word using twice the length as the field width.
28.11	(Converting Fahrenheit Temperature to Celsius) Write a program that converts integer Fahrenheit temperatures from 0 to 212 degrees to floating-point Celsius temperatures with three digits of precision. Use the formula celsius = 5.0 / 9.0 * ( fahrenheit - 32 );   to perform the calculation. The output should be printed in two right-justified columns of 10 characters each, and the Celsius temperatures should be preceded by a sign for both positive and negative values.
28.12	Write a program to test all the escape sequences in Fig. 28.23. For the escape sequences that move the cursor, print a character before and after the escape sequence so that it is clear where the cursor has moved.
28.13	Write a program that uses the conversion character g to output the value 9876.12345. Print the value with precisions ranging from 1 to 9.