《数字格式化》NumberFormat类的使用

[size=large]实例1：默认数据格式化[/size]

package com.meixin.classuse;

import java.text.NumberFormat;

public class DefaultNumberFormat
{
	public static void defaultNumberFormat()
	{

		int i = 123456;

		double x = 882323.23523;

		double p = 0.528;

		double c = 52.83;

		System.out.println("--------------------------------------");

		//实例化NumberFormat需要使用NumberFormat的getInstance()方法
		NumberFormat nf = NumberFormat.getInstance();
		//默认格式化int类型，结果已分节
		//结果：Integer 123456 is displayed as 123,456
		System.out.println("Integer " + i + " is displayed as " + nf.format(i));
		//默认格式化double类型，结果保留三位小数，已分节
		//结果：Double 882323.23523 is displayed as 882,323.235
		System.out.println("Double " + x + " is displayed as " + nf.format(x));

		System.out.println("--------------------------------------");

		//实例化为整型数据格式化
		NumberFormat nfInt = NumberFormat.getIntegerInstance();
		//默认，结果：Integer 123456 is displayed as 123,456
		System.out.println("Integer " + i + " is displayed as "
				+ nfInt.format(i));

		System.out.println("--------------------------------------");

		//实例化为数据格式化
		NumberFormat nfNumber = NumberFormat.getNumberInstance();
		//结果：Double 882323.23523 is displayed as 882,323.235
		System.out.println("Double " + x + " is displayed as "
				+ nfNumber.format(x));

		System.out.println("--------------------------------------");

		//百分数格式化
		NumberFormat nfPercent = NumberFormat.getPercentInstance();
		//结果已四舍五入
		//结果：Percent 0.528 is displayed as 53%
		System.out.println("Percent " + p + " is displayed as "
				+ nfPercent.format(p));

		System.out.println("--------------------------------------");

		//货币型格式化
		NumberFormat nfCurrency = NumberFormat.getCurrencyInstance();
		//结果：Currency 52.83 is displayed as ￥52.83
		System.out.println("Currency " + c + " is displayed as "
				+ nfCurrency.format(c));
	}

	public static void main(String[] args)
	{
		defaultNumberFormat();
		System.out.println();
	}

}

[size=large]实例2：自定义数据格式化[/size]

package com.meixin.classuse;

import java.text.DecimalFormat;

public class CustomNumberFormat
{

	public static void customNumberFormat()
	{

		double x = 100000.0 / 3;

		// default output is 33333.333333333336
		System.out.println("default output is " + x);
		// 33,333.33
		System.out.println(new DecimalFormat("###,###.##").format(x));
		// 33333.33
		System.out.println(new DecimalFormat("####.##").format(x));
		// 33333.33
		System.out.println(new DecimalFormat("####.00").format(x));
		// 33333.33
		System.out.println(new DecimalFormat("####.0#").format(x));
		// 0033333.33
		System.out.println(new DecimalFormat("0000000.##").format(x));
		// $33,333.33
		System.out.println(new DecimalFormat("$###,###.##").format(x));
		// 3.333E4
		System.out.println(new DecimalFormat("0.###E0").format(x));
		// 3333333.33%
		System.out.println(new DecimalFormat("00.##%").format(x));

		System.out.println("--------------------------------------");

		double y = 23232323.0012;
		//default output is 2.32323230012E7
		System.out.println("default output is " + y);
		//23,232,323
		System.out.println(new DecimalFormat("###,###.##").format(y));
		//23232323
		System.out.println(new DecimalFormat("####.##").format(y));
		//23232323.00
		System.out.println(new DecimalFormat("####.00").format(y));
		//23232323.0
		System.out.println(new DecimalFormat("####.0#").format(y));
		//0023232323
		System.out.println(new DecimalFormat("0000000000.##").format(y));
		//$23,232,323
		System.out.println(new DecimalFormat("$###,###.##").format(y));
		//2.323E7
		System.out.println(new DecimalFormat("0.###E0").format(y));
		//2323232300.12%
		System.out.println(new DecimalFormat("00.##%").format(y));
	}

	public static void main(String[] args)
	{
		customNumberFormat();
		System.out.println();
	}

}