printf formatted output

Converter description:

%s                   string type
%c                   character type
%b                   boolean type
%d                   integer type (decimal)
%x                   integer type (hexadecimal)
%o                   integer type (octal)
%f                    floating point type
%a                   hex floating point type
%e                   exponent type
%g                   generic floating point type (the shorter of the f and e types)
%h                   hash code
%%                  percent type
%n                   newline
%tx                  date and time type (x represents a different date and time converter

Example

System.out.printf("字符串类型: %s %s %s %n", "周杰伦", "林俊杰", "张学友");
System.out.printf("字符类型: %c 只能输入一个字符  %n", 'a');
System.out.printf("布尔类型: %b %n", true);
System.out.printf("整数类型(十进制): %d %n", 10);
System.out.printf("整数类型(十六进制): %x %n", 10);
System.out.printf("整数类型(八进制): %o %n", 10);
System.out.printf("浮点类型: %f %n", 10.0);
System.out.printf("十六进制浮点类型: %a %n", 10.0);
System.out.printf("指数类型: %e %n", 10.0);
System.out.printf("通用浮点类型(f和e类型中较短的): %g %n", 10.0);
System.out.printf("散列码: %h %n", 10.0);
System.out.printf("百分比类型: %d%% %n", 10);

Output result:

字符串类型: 周杰伦 林俊杰 张学友 
字符类型: a 只能输入一个字符  
布尔类型: true 
整数类型(十进制): 10 
整数类型(十六进制): a 
整数类型(八进制): 12 
浮点类型: 10.000000 
十六进制浮点类型: 0x1.4p3 
指数类型: 1.000000e+01 
通用浮点类型(f和e类型中较短的): 10.0000 
散列码: 40240000 
百分比类型: 10% 

Flags with converters

+ Add sign                        0 for positive or negative numbers with 0 spaces in front of numbers Add specified number of spaces before integers , "," to group numbers ( negative numbers are enclosed in parentheses # If it is a floating point number, it includes a decimal point, if it is hexadecimal or In octal, add 0x or 0 < format the parameter described by the previous converter $ formatted parameter index
                       
                  
                       
                      
                       
                      
                       

System.out.printf("\"+\": %+d %n",10);
System.out.printf("\"0\": %04d %n",10);
System.out.printf("\"空格\" % 4d %n",10);
System.out.printf("\",\": %,f %n",1000000.0);
System.out.printf("\"(\": %(f %n",-100.00);
System.out.printf("\"#\": %#x %n",10);
System.out.printf("\"<\": %f和%<1.2f %n",10.223);
System.out.printf("\"$\": %1$d %2$s %n",13,"a");

Output result:

"+": +10 
"0": 0010 
"空格"   10 
",": 1,000,000.000000 
"(": (100.000000) 
"#": 0xa 
"<": 10.223000和10.22 
"$": 13 a 

Date and event string formatting

cIncludes                        all date and time information
F                      "Year-Month-Day" format
D                     "Month/Day/Year" format
r                      "HH:MM:SS PM" format (12-hour clock)
T                     "HH:MM:SS" format ( 24-hour)
R                     "HH:MM" format (24-hour)

Date date = new Date();
System.out.printf("%tc %n", date);
System.out.printf("%tF %n", date);
System.out.printf("%tD %n", date);
System.out.printf("%tT %n", date);
System.out.printf("%tR %n", date);
System.out.printf("%tF %tT %n",date,date);

Output result:

星期日 十二月 17 16:15:39 CST 2017 
2017-12-17 
12/17/17 
16:15:39 
16:15 
2017-12-17 16:15:39