formatnum.html
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<h3>
e311.
Formatting a Number Using a Custom Format</h3>
A pattern of special characters is used to specify the format of the
number. This example demonstrates some of the characters. For a
complete listing, see the javadoc documentation for the
<code>DecimalFormat</code> class.
<P> There is no symbol that either displays a digit or a blank if
no digit present. Hence, it is not possible to format a number so that
it will have a specific width. To achieve a specific width, you must
manually pad the formatted number.
<pre>
// The 0 symbol shows a digit or 0 if no digit present
NumberFormat formatter = new DecimalFormat("000000");
String s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -001235
// notice that the number was rounded up
// The # symbol shows a digit or nothing if no digit present
formatter = new DecimalFormat("##");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1235
s = formatter.format(<font color="#0066ff"><i>0</i></font>); // 0
formatter = new DecimalFormat("##00");
s = formatter.format(<font color="#0066ff"><i>0</i></font>); // 00
// The . symbol indicates the decimal point
formatter = new DecimalFormat(".00");
s = formatter.format(<font color="#0066ff"><i>-.567</i></font>); // -.57
formatter = new DecimalFormat("0.00");
s = formatter.format(<font color="#0066ff"><i>-.567</i></font>); // -0.57
formatter = new DecimalFormat("#.#");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1234.6
formatter = new DecimalFormat("#.######");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1234.567
formatter = new DecimalFormat(".######");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1234.567
formatter = new DecimalFormat("#.000000");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1234.567000
// The , symbol is used to group numbers
formatter = new DecimalFormat("#,###,###");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1,235
s = formatter.format(<font color="#0066ff"><i>-1234567.890</i></font>); // -1,234,568
// The ; symbol is used to specify an alternate pattern for negative values
formatter = new DecimalFormat("#;(#)");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // (1235)
// The ' symbol is used to quote literal symbols
formatter = new DecimalFormat("'#'#");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -#1235
formatter = new DecimalFormat("'abc'#");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -abc1235
</pre>
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Related Examples
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e312. <a class="eglink" href="Numbers.html?l=rel">
Formatting and Parsing a Number for a Locale
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e313. <a class="eglink" href="FormatNumExp.html?l=rel">
Formatting a Number in Exponential Notation
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e314. <a class="eglink" href="Currency.html?l=rel">
Formatting and Parsing Locale-specific Currency
</a>
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e315. <a class="eglink" href="Percent.html?l=rel">
Formatting and Parsing a Locale-specific Percentage
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Dates
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Messsages
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Times
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<a class="eglink" href="/egs/java.text/pkg.html?l=rel#Words%20and%20Sentences">
Words and Sentences
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