Java Format Justifying Output
Description
By default, all output is right-justified.
You can force output to be left-justified by placing a minus sign directly after the %.
Syntax
fmt.format("|%#d|", 123.123);
or
fmt.format("|%#.#d|", 123.123);Example
For instance, %-10.2f left-justifies a floating-point number with two decimal
places in a 10-character field.
import java.util.Formatter;
// ww w. j a va 2 s . c om
public class Main {
public static void main(String args[]) {
Formatter fmt = new Formatter();
// Right justify by default
fmt.format("|%10.2f|", 123.123);
System.out.println(fmt);
// Now, left justify.
fmt = new Formatter();
fmt.format("|%-10.2f|", 123.123);
System.out.println(fmt);
}
}
The output:
Example 2
Use Formatter to left-justify strings within a table
import java.util.Formatter;
// w ww. j a v a 2 s. co m
public class Main {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%-12s %12s\n\n", "Source", "Loss");
fmt.format("%-12s %,12d\n", "Retail", 1232675);
System.out.println(fmt);
}
}
The code above generates the following result.
Example 3
Use Formatter to vertically align numeric values
import java.util.Formatter;
/* w w w . j a v a 2 s . c o m*/
public class Main {
public static void main(String[] argv) throws Exception {
double data[] = { 12.3, 45.6, -7.89, -1.0, 1.01 };
Formatter fmt = new Formatter();
fmt.format("%12s %12s\n", "Value", "Cube Root");
for (double v : data) {
fmt.format("%12.4f %12.4f\n", v, Math.cbrt(v));
}
System.out.println(fmt);
}
}
The code above generates the following result.
Value Cube Root/*from w w w.j a v a 2s .c o m*/
12.3000 2.3084
45.6000 3.5726
-7.8900 -1.9908
-1.0000 -1.0000
1.0100 1.0033
Example 4
public class Main {
public static void main(String args[]) {
String format = "|%1$-10s|%2$10s|%3$-20s|\n";
System.out.format(format, "A", "AA", "AAA");
System.out.format(format, "B", "", "BBBBB");
System.out.format(format, "C", "CCCCC", "CCCCCCCC");
/*from w w w .ja v a 2s.c om*/
String ex[] = { "E", "java2s.com", "E" };
System.out.format(String.format(format, (Object[]) ex));
}
}
The code above generates the following result.
