Conditional Execution - Building Java Programs: A Back to Basics Approach - page 260

Table 4.6 Common Format Specifiers

Specifier Result

Integer

%d

Integer, right-aligned, 8-space-wide field

%8d

Integer, left-aligned, 6-space-wide field

% 6d

Floating-point number

%f

Floating-point number, right-aligned, 12-space-wide field

%12f

Floating-point number, rounded to nearest hundredth

%.2f

Floating-point number, rounded to nearest thousandth, 16-space-wide field

%16.3f

String

%s

String, right-aligned, 8-space-wide field

%8s

String, left-aligned, 9-space-wide field

% 9s

As a comprehensive example, suppose that the following variables have been
declared to represent information about a student:

int score = 87;
double gpa = 3.18652;
String name = "Jessica";

The following code sample prints the preceding variables with several format
specifiers:

System.out.printf("student name: %10s\n", name);
System.out.printf("exam score : %10d\n", score);
System.out.printf("GPA : %10.2f\n", gpa);

The code produces the following output:

student name: Jessica
exam score : 87
GPA : 3.19

The three values line up on their right edge, because we print all of them with a
width of 10. The printf method makes it easy to line up values in columns in this
way. Notice that the student's GPA rounds to 3.19, because of the 2 in that variable's
format specifier. The specifier 10.2 makes the value fit into an area 10 characters
wide with exactly 2 digits after the decimal point.
Let's return to our multiplication table example. Now that we know about printf ,
we can print the table with right-aligned numbers relatively easily. We'll right-align
the numbers into fields of width 5:

for (int i = 1; i <= 10; i++) {
for (int j = 1; j <= 10; j++) {