java中小数取整规则

import com.google.common.collect.Lists;

import cn.hutool.core.util.NumberUtil;
import cn.hutool.core.util.StrUtil;


// TODO XiangPeng 取整规则实现
public enum RoundingRuleEnum {

    ROUND_YUAN("ROUND_YUAN", "四舍五入到元") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 0, RoundingMode.HALF_UP);
        }
    },

    ROUND_JIAO("ROUND_JIAO", "四舍五入到角") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 1, RoundingMode.HALF_UP);
        }
    },

    ROUND_CENT("ROUND_CENT", "四舍五入到分") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 2, RoundingMode.HALF_UP);
        }
    },

    ROUNDUP_YUAN("ROUNDUP_YUAN", "见角进元") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 0, RoundingMode.CEILING);
        }
    },

    ROUNDUP_JIAO("ROUNDUP_JIAO", "见分进角") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 1, RoundingMode.CEILING);
        }
    },

    ROUND_DOWN_CENT("ROUNDDOWN_CENT", "舍入到分") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 2, RoundingMode.DOWN);
        }
    },

    ROUND_DOWN_JIAO("ROUNDDOWN_JIAO", "舍入到角") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 1, RoundingMode.DOWN);
        }
    },

    ROUND_DOWN_YUAN("ROUNDDOWN_YUAN", "舍入到元") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 0, RoundingMode.DOWN);
        }
    },

    ROUNDUP_JIAO_FEN_YUAN("ROUNDUP_JIAOFEN_YUAN", "见角分进元") {
        @Override
        public BigDecimal round(BigDecimal number) {
            return NumberUtil.round(number, 0, RoundingMode.CEILING);
        }
    },

    ROUNDUP_INF_INIT_CENT("ROUNDUP_INFINIT_CENT", "无限进位到分") {
        @Override
        public BigDecimal round(BigDecimal number) {
            if (number.scale() <= 2 || NumberUtil.isLessOrEqual(NumberUtil.sub(number, ROUND_DOWN_YUAN.round(number)),
                    BigDecimal.ZERO)) {
                return number;
            }
            return NumberUtil.add(new BigDecimal(new Formatter().format("%.2f", number).toString()), 0.01);
        }
    },

    ROUNDUP_INF_INIT_JIAO("ROUNDUP_INFINIT_JIAO", "无限进位到角") {
        @Override
        public BigDecimal round(BigDecimal number) {
            if (number.scale() <= 1 || NumberUtil.isLessOrEqual(NumberUtil.sub(number, ROUND_DOWN_YUAN.round(number)),
                    BigDecimal.ZERO)) {
                return number;
            }
            return NumberUtil.add(new BigDecimal(new Formatter().format("%.1f", number).toString()), 0.1);
        }
    },

    ROUNDUP_INF_INIT_YUAN("ROUNDUP_INFINIT_YUAN", "无限进位到元") {
        @Override
        public BigDecimal round(BigDecimal number) {
            if (number.scale() <= 0 || NumberUtil.isLessOrEqual(NumberUtil.sub(number, ROUND_DOWN_YUAN.round(number)),
                    BigDecimal.ZERO)) {
                return number;
            }
            return NumberUtil.add(ROUND_DOWN_YUAN.round(number), 1);
        }
    };

    private String code;

    private String name;

    public static RoundingRuleEnum getByCode(String code) {
        if (StrUtil.isBlank(code)) {
            return null;
        }
        return ListUtil.filterOne(Lists.newArrayList(RoundingRuleEnum.values()), e -> e.getCode().equals(code));

    }

    
    public abstract BigDecimal round(BigDecimal number);

    RoundingRuleEnum(String code, String name) {
        this.code = code;
        this.name = name;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

}