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== Demonstrate the %g format specifier. ==



<source lang="java">
import java.util.Formatter;
public class Main{
public static void main(String args[]) {
Formatter fmt = new Formatter();
for (double i = 1000; i < 1.0e+10; i *= 100) {
fmt.format("%g ", i);
System.out.println(fmt);
}
}
}
/*
1000.00
1000.00 100000
1000.00 100000 1.00000e+07
1000.00 100000 1.00000e+07 1.00000e+09
*/</source>



== Demonstrating the space format specifiers ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("% d", -100);
System.out.println(fmt);
fmt = new Formatter();
fmt.format("% d", 100);
System.out.println(fmt);
fmt = new Formatter();
fmt.format("% d", -200);
System.out.println(fmt);
fmt = new Formatter();
fmt.format("% d", 200);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>-100
100
-200
200</pre>

== format: %#o ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%#o", 1);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>01</pre>

== format: %#x ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%#x", 1);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>0x1</pre>

== Left justification ==

By default, all output is right-justified.
You can force output to
be left-justified by placing a minus sign directly after the %.
For example, %-10.2f left-justifies a floating-point number with two decimal places in a
ten-character field.



<source lang="java">
import java.util.*;
public class MainClass {
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);
}
}</source>



<pre class=codeResult>| 123.12|
|123.12 |</pre>

== The 0 flag ==

The 0 flag causes output to be padded with zeros rather than spaces.
The 0 flag can be used with all format specifiers except %n.



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%05d", 100);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>00100</pre>

== The Comma Flag(,) : to add grouping specifiers ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%,.2f", 4356783497.34);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>4,356,783,497.34</pre>

== The # Flag ==

The # flag can be applied to the %o, %x, %e, and %f format specifiers.
For %e and %f, the # ensures that there will be a decimal point even if
there are no decimal digits.
Preceding the %x specifier with a #, the hexadecimal number will be printed with a 0x prefix.
Preceding the %o specifier with # causes the number to be printed with a leading zero.



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%#e", 1F);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>1.000000e+00</pre>

== The %n inserts a newline: the %n and %% format specifiers ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("Copying file%nTransfer is %d%% complete", 88);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>Copying file
Transfer is 88% complete</pre>

== The Space, +, 0, and "(" Flags: To show a "+" sign before positive numeric values, add the + flag ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
// Right justify by default.
fmt.format("%+d", 100);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>+100</pre>

== To show negative numeric output inside parentheses, rather than with a leading -, use the "(" flag ==



<source lang="java">
import java.util.Formatter;
public class MainClass {
public static void main(String args[]) {
Formatter fmt = new Formatter();
fmt.format("%(d", -100);
System.out.println(fmt);
}
}</source>



<pre class=codeResult>(100)</pre>

== Using the Format Flags ==

Formatter uses a set of format flags to control various aspects of a conversion.
A format flag follows the % in a format specification.
FlagEffect-Left justification#Alternate conversion format0Output is padded with zeros rather than spacesspacePositive numeric output is preceded by a space+Positive numeric output is preceded by a + sign,Numeric values include grouping separators(Negative numeric values are enclosed within parentheses

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