Number type display, amount with area, rounded number, percentage number

public static void main(String[] args) {
		// do not use formatted output numbers
		double d = 10.0 / 3.0;
		System.out.println("Unformatted output: " + d);

		// use the local default format to output the number
		NumberFormat numberFormat = NumberFormat.getNumberInstance();
		//set maximum precision
		numberFormat.setMaximumFractionDigits(4);
		numberFormat.setMinimumFractionDigits(1);
		// way of rounding
		numberFormat.setRoundingMode(RoundingMode.HALF_DOWN);
		String numberString = numberFormat.format(d);
		System.out.println("Local default format output number: " + numberString);

		// output currency value using local default format
		NumberFormat currencyFormat = NumberFormat.getCurrencyInstance();
		System.out.println("The local default format output currency value: " + currencyFormat.format(d));

		// output percentage using local default format
		NumberFormat percentFormat = NumberFormat.getPercentInstance();
		System.out.println("Percentage output in local default format: " + percentFormat.format(d));

		// The format of the number representation in different countries and regions is also different. such as Germany
		// Use German formatted output numbers
		NumberFormat numberFormatG = NumberFormat.getNumberInstance(Locale.GERMANY);
		System.out.println("German digital output format: " + numberFormatG.format(d));

		// use the German currency output form
		NumberFormat currencyFormatG = NumberFormat.getCurrencyInstance(Locale.GERMANY);
		System.out.println("German currency output format: " + currencyFormatG.format(d));

		// use the US currency output form
		NumberFormat currencyFormatA = NumberFormat.getCurrencyInstance(Locale.US);
		System.out.println("US currency output format: " + currencyFormatA.format(d));

		// use the German percent output format
		NumberFormat percentFormatG = NumberFormat.getPercentInstance(Locale.GERMANY);
		System.out.println("German percent output format: " + percentFormatG.format(d));
	}

The results show that:

Unformatted output: 3.3333333333333335
Number of outputs in local default format: 3.3333
Local default format output currency value: ￥3.33
Local default format output percentage: 333%
German digital output form: 3,333
German currency output form: 3,33 €
US currency output form: $3.33
German percent output format: 333%