我有以下方法，如果没有别的，我想缩短或加快。欢迎所有评论:

Bellow 方法获取一个日期对象，将其格式化(“EEE hh:mma MMM d, yyyy”)，然后判断日期是今天还是昨天，如果是，则返回“(昨天 | 今天) hh:mma"格式的字符串。

    public static String formatToYesterdayOrToday(String date) {
    SimpleDateFormat sdf = new SimpleDateFormat("EEE hh:mma MMM d, yyyy");
    Date in = null;

    try {
        in = sdf.parse(date);
    } catch (ParseException e) {
        log.debug("Date parsing error:", e);
    }

    Calendar x = Calendar.getInstance();
    x.setTime(in);

    String hour = Integer.toString(x.get(Calendar.HOUR));
    String minute = Integer.toString(x.get(Calendar.MINUTE));
    String pm_am = x.get(Calendar.AM_PM) == Calendar.AM ? "AM" : "PM";

    x.set(Calendar.HOUR, 0);
    x.set(Calendar.HOUR_OF_DAY, 0);
    x.set(Calendar.MINUTE, 0);
    x.set(Calendar.SECOND, 0);
    x.set(Calendar.MILLISECOND, 0);

    Calendar today = Calendar.getInstance();
    today.set(Calendar.HOUR, 0);
    today.set(Calendar.HOUR_OF_DAY, 0);
    today.set(Calendar.MINUTE, 0);
    today.set(Calendar.SECOND, 0);
    today.set(Calendar.MILLISECOND, 0);

    Calendar yesterday = Calendar.getInstance();
    yesterday.set(Calendar.HOUR, 0);
    yesterday.set(Calendar.HOUR_OF_DAY, 0);
    yesterday.set(Calendar.MINUTE, 0);
    yesterday.set(Calendar.SECOND, 0);
    yesterday.set(Calendar.MILLISECOND, 0);
    yesterday.add(Calendar.DATE, -1);

    if (x.compareTo(today) == 0) {
        return "Today " + hour + ":" + minute + pm_am;
    }
    if (x.compareTo(yesterday) == 0) {
        return "Yesterday " + hour + ":" + minute + pm_am;
    }
    return date;
}

最佳答案

以下是使用标准 API 改进它的方法:

public static String formatToYesterdayOrToday(String date) throws ParseException {
    Date dateTime = new SimpleDateFormat("EEE hh:mma MMM d, yyyy").parse(date);
    Calendar calendar = Calendar.getInstance();
    calendar.setTime(dateTime);
    Calendar today = Calendar.getInstance();
    Calendar yesterday = Calendar.getInstance();
    yesterday.add(Calendar.DATE, -1);
    DateFormat timeFormatter = new SimpleDateFormat("hh:mma");

    if (calendar.get(Calendar.YEAR) == today.get(Calendar.YEAR) && calendar.get(Calendar.DAY_OF_YEAR) == today.get(Calendar.DAY_OF_YEAR)) {
        return "Today " + timeFormatter.format(dateTime);
    } else if (calendar.get(Calendar.YEAR) == yesterday.get(Calendar.YEAR) && calendar.get(Calendar.DAY_OF_YEAR) == yesterday.get(Calendar.DAY_OF_YEAR)) {
        return "Yesterday " + timeFormatter.format(dateTime);
    } else {
        return date;
    }
}

以下是使用 Jodatime 实现的方法:

public static String formatToYesterdayOrToday(String date) {
    DateTime dateTime = DateTimeFormat.forPattern("EEE hh:mma MMM d, yyyy").parseDateTime(date);
    DateTime today = new DateTime();
    DateTime yesterday = today.minusDays(1);
    DateTimeFormatter timeFormatter = DateTimeFormat.forPattern("hh:mma");

    if (dateTime.toLocalDate().equals(today.toLocalDate())) {
        return "Today " + timeFormatter.print(dateTime);
    } else if (dateTime.toLocalDate().equals(yesterday.toLocalDate())) {
        return "Yesterday " + timeFormatter.print(dateTime);
    } else {
        return date;
    }
}

关于java - 简化在Java静态方法中用 "today"和 "yesterday"字符串替换日期对象，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/4292139/