Java printf( ) Method Quick Reference, Cheat Sheet of Java Programming

Download Java printf( ) Method Quick Reference and more Cheat Sheet Java Programming in PDF only on Docsity! Java printf( ) Method Quick Reference System.out.printf( “format-string” [, arg1, arg2, … ] ); Format String: Composed of literals and format specifiers. Arguments are required only if there are format specifiers in the format string. Format specifiers include: flags, width, precision, and conversion characters in the following sequence: % [flags] [width] [.precision] conversion-character ( square brackets denote optional parameters ) Flags: - : left-justify ( default is to right-justify ) + : output a plus ( + ) or minus ( - ) sign for a numerical value 0 : forces numerical values to be zero-padded ( default is blank padding ) , : comma grouping separator (for numbers > 1000) : space will display a minus sign if the number is negative or a space if it is positive Width: Specifies the field width for outputting the argument and represents the minimum number of characters to be written to the output. Include space for expected commas and a decimal point in the determination of the width for numerical values. Precision: Used to restrict the output depending on the conversion. It specifies the number of digits of precision when outputting floating-point values or the length of a substring to extract from a String. Numbers are rounded to the specified precision. Conversion-Characters: d : decimal integer [byte, short, int, long] f : floating-point number [float, double] c : character Capital C will uppercase the letter s : String Capital S will uppercase all the letters in the string h : hashcode A hashcode is like an address. This is useful for printing a reference n : newline Platform specific newline character- use %n instead of \n for greater compatibility Examples: System.out.printf("Total is: $%,.2f%n", dblTotal); System.out.printf("Total: %-10.2f: ", dblTotal); System.out.printf("% 4d", intValue); System.out.printf("%20.10s\n", stringVal); String s = "Hello World"; System.out.printf("The String object %s is at hash code %h%n", s, s); String class format( ) method: You can build a formatted String and assign it to a variable using the static format method in the String class. The use of a format string and argument list is identical to its use in the printf method. The format method returns a reference to a String. Example: String grandTotal = String.format("Grand Total: %,.2f", dblTotal);