JAVA和JODA Date解析即使格式错误也不会抛出异常

Question

我希望针对以下代码和输入抛出异常:

SimpleDateFormat getDateTimeFormat(String requiredFormat)
{
    SimpleDateFormat dateTimeFormat = new SimpleDateFormat(requiredFormat);
    //this will make sure that if parsing fails exception is thrown
    dateTimeFormat.setLenient(false);
    return dateTimeFormat;
}
Date date = getDateTimeFormat("MM/dd/yyyy HH:mm").parse(estimatedDeliveryDttm);

输入:10/25/16 17:46

我期待解析异常，因为年份不是“yyyy”，但我得到的年份是“0016”，这是我不想要的。我不能使用 JAVA 8。我已经尝试过 JAVA 7(包括解析位置方法)和 JODA Date Time API。

Answer 1

来自 SimpleDateFormat 的 Javadocs

Year: If the formatter's Calendar is the Gregorian calendar, thefollowing rules are applied.

For formatting, if the number of patternletters is 2, the year is truncated to 2 digits; otherwise it isinterpreted as a number.

For parsing, if the number of pattern lettersis more than 2, the year is interpreted literally, regardless of thenumber of digits. So using the pattern "MM/dd/yyyy", "01/11/12" parsesto Jan 11, 12 A.D.

For parsing with the abbreviated year pattern ("y"or "yy"),SimpleDateFormat must interpret the abbreviated yearrelative to some century. It does this by adjusting dates to be within80 years before and 20 years after the time the SimpleDateFormatinstance is created. For example, using a pattern of "MM/dd/yy" and aSimpleDateFormat instance created on Jan 1, 1997, the string"01/11/12" would be interpreted as Jan 11, 2012 while the string"05/04/64" would be interpreted as May 4, 1964. During parsing, onlystrings consisting of exactly two digits, as defined byCharacter.isDigit(char), will be parsed into the default century. Anyother numeric string, such as a one digit string, a three or moredigit string, or a two digit string that isn't all digits (forexample, "-1"), is interpreted literally. So "01/02/3" or "01/02/003"are parsed, using the same pattern, as Jan 2, 3 AD. Likewise, "01/02/-3" is parsed as Jan 2, 4 BC.

请参阅上面的粗体点，它解释了您所看到的行为。