Formatter Format Strings

Question 1

What is Formatter?

Answer 1

An interpreter for printf-style format strings.

Question 2

What does formatter format option ‘b’, ‘B’ represent?

Answer 2

If the argument arg is null, then the result is “false”. If arg is a boolean or Boolean, then the result is the string returned by String.valueOf(arg). Otherwise, the result is “true”.

Question 3

What does formatter format option ‘h’, ‘H’ represent?

Answer 3

If the argument arg is null, then the result is “null”. Otherwise, the result is obtained by invoking Integer.toHexString(arg.hashCode())

Question 4

What does formatter format option ‘s’, ‘S’ represent?

Answer 4

If the argument arg is null, then the result is “null”. If arg implements Formattable, then arg.formatTo is invoked. Otherwise, the result is obtained by invoking arg.toString().

Question 5

What does formatter format option ‘c’, ‘C’ represent?

Answer 5

The result is a Unicode character

Question 6

What does formatter format option ‘d’ represent?

Answer 6

The result is formatted as a decimal integer

Question 7

What does formatter format option ‘o’ represent?

Answer 7

The result is formatted as an octal integer

Question 8

What does formatter format option ‘x’, ‘X’ represent?

Answer 8

The result is formatted as a hexadecimal integer

Question 9

What does formatter format option ‘f’ represent?

Answer 9

The result is formatted as a decimal number

Question 10

What does formatter format option ‘t’, ‘T’ represent?

Answer 10

Prefix for date and time conversion characters. See Date/Time Conversions.

Question 11

What does formatter format option ‘n’ represent?

Answer 11

The result is the platform-specific line separator.

Question 12

What does formatter date/time format option ‘M’ represent?

Answer 12

Minute within the hour formatted as two digits with a leading zero as necessary, i.e. 00 - 59.

Question 13

What does formatter date/time format option ‘S’ represent?

Answer 13

Seconds within the minute, formatted as two digits with a leading zero as necessary, i.e. 00 - 60 (“60” is a special value required to support leap seconds).

Question 14

What does formatter date/time format option ‘p’ represent?

Answer 14

Locale-specific morning or afternoon marker in lower case, e.g.”am” or “pm”. Use of the conversion prefix ‘T’ forces this output to upper case.

Question 15

What does formatter date/time format options ‘e’ and ‘m’ represent?

Answer 15

Month. m formats as two digits with leading zeros as necessary, i.e. 01 - 13.

Question 16

What does formatter date/time format option ‘z’ represent?

Answer 16

RFC 822 style numeric time zone offset from GMT, e.g. -0800. This value will be adjusted as necessary for Daylight Saving Time. For long, Long, and Date the time zone used is the default time zone for this instance of the Java virtual machine.

Question 17

What does formatter date/time format option ‘Z’ represent?

Answer 17

A string representing the abbreviation for the time zone. This value will be adjusted as necessary for Daylight Saving Time. For long, Long, and Date the time zone used is the default time zone for this instance of the Java virtual machine. The Formatter’s locale will supersede the locale of the argument (if any).

Question 18

What does formatter date/time format option ‘B’ represent?

Answer 18

Locale-specific full month name, e.g. “January”, “February”.

Question 19

What does formatter date/time format option ‘b’ represent?

Answer 19

Locale-specific abbreviated month name, e.g. “Jan”, “Feb”.

Note the ‘h’ format can also be used in place of ‘b’

Question 20

What does formatter date/time format option ‘A’ represent?

Answer 20

Locale-specific full name of the day of the week, e.g. “Sunday”, “Monday”

Question 21

What does formatter date/time format option ‘a’ represent?

Answer 21

Locale-specific short name of the day of the week, e.g. “Sun”, “Mon”

Question 22

What does formatter date/Time format option ‘C’ represent?

Answer 22

Four-digit year divided by 100, formatted as two digits with leading zero as necessary, i.e. 00 - 99

Question 23

What does formatter date/time format option ‘Y’ represent?

Answer 23

Year, formatted as at least four digits with leading zeros as necessary, e.g. 0092 equals 92 CE for the Gregorian calendar.

Question 24

What does formatter date/time format option ‘y’ represent?

Answer 24

Last two digits of the year, formatted with leading zeros as necessary, i.e. 00 - 99.

Question 25

What does formatter date/time format option ‘j’ represent?

Answer 25

Day of year, formatted as three digits with leading zeros as necessary, e.g. 001 - 366 for the Gregorian calendar

Question 26

What does formatter date/time format option ‘d’ represent?

Answer 26

Day of month, formatted as two digits with leading zeros as necessary, i.e. 01 - 31

Question 27

What does formatter date/time format option ‘R’ represent?

Answer 27

Time formatted for the 24-hour clock as “%tH:%tM”

Question 28

What does formatter date/time format option ‘T’ represent?

Answer 28

Time formatted for the 24-hour clock as “%tH:%tM:%tS”.

Question 29

What does formatter date/time format option ‘r’ represent?

Answer 29

Time formatted for the 12-hour clock as “%tI:%tM:%tS %Tp”. The location of the morning or afternoon marker (‘%Tp’) may be locale-dependent.