問題描述

我正在讀取可能帶有或不帶有時區(qū)調(diào)整的日期字符串:yyyyMMddHHmmssz 或 yyyyMMddHHmmss.當字符串缺少區(qū)域時，我會將其視為 GMT.我沒有看到在 SimpleDateFormat 中創(chuàng)建可選部分的任何方法，但也許我遺漏了一些東西.有沒有辦法用 SimpleDateFormat 來做到這一點，還是我應該寫一個新的具體 DateFormat 來處理這個?

I'm reading in date strings that could be with or without a time zone adjustment: yyyyMMddHHmmssz or yyyyMMddHHmmss. When a string is missing a zone, I'll treat it as GMT. I'm not seeing any way to create optional sections in a SimpleDateFormat, but maybe I'm missing something. Is there a way to do this with a SimpleDateFormat, or should I just write a new concrete DateFormat to handle this?

推薦答案

我會創(chuàng)建兩個 SimpleDateFormat，一個有時區(qū)，一個沒有.您可以查看 String 的長度來確定使用哪一個.

I would create two SimpleDateFormat, one with a time zone and one without. You can look at the length of the String to determine which one to use.

聽起來您需要一個代表兩個不同 SDF 的 DateFormat.

Sounds like you need a DateFormat which delegates to two different SDF.

DateFormat df = new DateFormat() {
    static final String FORMAT1 = "yyyyMMddHHmmss";
    static final String FORMAT2 = "yyyyMMddHHmmssz";
    final SimpleDateFormat sdf1 = new SimpleDateFormat(FORMAT1);
    final SimpleDateFormat sdf2 = new SimpleDateFormat(FORMAT2);
    @Override
    public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) {
        throw new UnsupportedOperationException();
    }

    @Override
    public Date parse(String source, ParsePosition pos) {
        if (source.length() - pos.getIndex() == FORMAT1.length())
            return sdf1.parse(source, pos);
        return sdf2.parse(source, pos);
    }
};
System.out.println(df.parse("20110102030405"));
System.out.println(df.parse("20110102030405PST"));

這篇關于SimpleDateFormat 中的可選部分的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！