单位转换、保留小数、计算百分比【工具类】

实际开发中，经常会遇到单位转换、保留小数、计算百分比的场景，下面是我自己写的并实际使用的工具类，希望能帮到大家或者给大家参考

该工具类包括：

• 单位转换成万或亿
• 保留两位小数
• 计算百分比，保留两位小数
• 计算百分比，保留两位小数，若有效数字为0，则往后取到第一个不为零的
• 计算百分比，保留整数

public class NumberUtil {/*** 转换为亿* @param amount* @return*/public static BigDecimal formatToYI(BigDecimal amount) {if (amount == null) {return new BigDecimal(0);}return amount.divide(new BigDecimal(100000000), 2, BigDecimal.ROUND_HALF_UP);}/*** 转换为万* @param amount* @return*/public static BigDecimal formatToWAN(BigDecimal amount) {if (amount == null) {return new BigDecimal(0);}return amount.divide(new BigDecimal(10000), 2, BigDecimal.ROUND_HALF_UP);}/*** 转成万或亿* @param amount* @return*/public static String formatToWanOrYi(BigDecimal amount) {if (amount == null) {return "0";}if (amount.compareTo(new BigDecimal(10000000)) < 0) {//如果小于1亿return amount.divide(new BigDecimal(10000), 2, BigDecimal.ROUND_HALF_UP).stripTrailingZeros().toPlainString() + "万";}return amount.divide(new BigDecimal(100000000), 2, BigDecimal.ROUND_HALF_UP).stripTrailingZeros().toPlainString() + "亿";}/*** 保留两位小数* @param amount* @return*/public static BigDecimal formatTwo(BigDecimal amount) {if (amount == null) {return new BigDecimal(0);}return amount.setScale(2, BigDecimal.ROUND_HALF_UP);}/*** 计算百分比 保留两位小数* @param num1* @param num2* @return*/public static String getPercent(long num1, long num2) {String rate = "0.00%";String format = "0.00";if (num1 != 0 && num2 != 0) {DecimalFormat dec = new DecimalFormat(format);rate = dec.format((double) num1 / num2*100) + "%";} else if (num1 != 0 && num2 == 0) {rate = "100.00%";}return rate;}/*** 计算百分比 保留两位小数* @param num1* @param num2* @return*/public static String getPercent(BigDecimal num1, BigDecimal num2) {String rate = "0.00%";String format = "0.00";if (num1.intValue() != 0 && num2.intValue() != 0) {DecimalFormat dec = new DecimalFormat(format);rate = dec.format(num1.divide(num2, 4, BigDecimal.ROUND_HALF_UP).multiply(new BigDecimal(100)).doubleValue()) + "%";} else if (num1.intValue() != 0 && num2.intValue() == 0) {rate = "100.00%";}return rate;}/*** 计算百分比，保留两位小数，若有效数字为0，则往后取到第一个不为零的* @param num1* @param num2* @return*/public static String getPercentPro(long num1, long num2) {String rate = "0.00%";String format = "0.00";if (num1 != 0 && num2 != 0) {double v = (double) num1 / num2 * 100;if (v >= 0.01) {DecimalFormat dec = new DecimalFormat(format);rate = dec.format(v) + "%";} else {while (true) {DecimalFormat dec = new DecimalFormat(format);String format1 = dec.format(v);if (Double.parseDouble(format1) > 0) {rate = format1 + "%";break;} else {format = format + "0";}}}} else if (num1 != 0 && num2 == 0) {rate = "100.00%";}return rate;}/*** 计算百分比 保留整数* @param num1* @param num2* @return*/public static String getPercentNoPoint(BigDecimal num1, BigDecimal num2) {String rate = "0%";String format = "0";if (num1.intValue() != 0 && num2.intValue() != 0) {DecimalFormat dec = new DecimalFormat(format);rate = dec.format(num1.divide(num2, 2, BigDecimal.ROUND_HALF_UP).multiply(new BigDecimal(100)).doubleValue()) + "%";} else if (num1.intValue() != 0 && num2.intValue() == 0) {rate = "100%";}return rate;}