0 → "零", 1 → "壹", ..., 9 → "玖"  

// 分節(jié)處理示例  
String[] sections = {"", "萬", "億", "萬億"};  
for (int i = 0; amount > 0; i++) {  
    int section = (int)(amount % 10000);  
    amount /= 10000;  
    if (section > 0) {  
        result = convertSection(section) + sections[i] + result;  
    }  
}  

private static final String[] CN_NUMBERS = {"零", "壹", "貳", "叁", "肆", "伍", "陸", "柒", "捌", "玖"};  
private static final String[] CN_UNITS = {"", "拾", "佰", "仟"};  

// 處理角分  
long fen = Math.round((amount - yuan) * 100);  
int jiao = (int)(fen / 10);  
int fenPart = (int)(fen % 10);  
if (jiao > 0 || fenPart > 0) {  
    result += CN_NUMBERS[jiao] + (jiao > 0 ? "角" : "");  
    result += CN_NUMBERS[fenPart] + (fenPart > 0 ? "分" : "");  
}  

if (amount < 0) {  
    return "負(fù)" + toChineseUpper(-amount);  
}  
if (amount > MAX_VALUE) {  
    throw new IllegalArgumentException("金額超出處理范圍");  
}  

public interface MoneyConverter {  
    String convert(BigDecimal amount);  
}  
public class ChineseConverter implements MoneyConverter { ... }  

public class MoneyConverter {  
    private static final String[] CN_NUMBERS = {"零", "壹", "貳", "叁", "肆", "伍", "陸", "柒", "捌", "玖"};  
    private static final long MAX_VALUE = 9999999999999999L;  

    public static String toChineseUpper(long amount) {  
        if (amount == 0) return "零元整";  
        // 實現(xiàn)邏輯...  
    }  
}  

@Test  
public void testConversion() {  
    assertEquals("壹萬貳仟叁佰肆拾伍元陸角柒分", MoneyConverter.toChineseUpper(12345.67));  
    assertEquals("玖萬億零壹元整", MoneyConverter.toChineseUpper(90000000000001L));  
}