Java中如何将String转成Date

Java中如何将String转成Date

最近在开发Json数据反序列化为Java对象的时候发现spring mvc 和 Jackson 对Date类型对支持不是特别好，虽然在Java对象序列化为Json数据的过程中提供了便利的注解，但是反序列化却没有，于是就引出了下面的问题，我需要手工的将字符串转换为Date类型的数据，java.text.SimpleDateFormat 为我们提供了这种转换的基础设施。如下列出了的格式化模式的简单定义，如果 ‘M’ 大于等于3位, 月份会显示为字母，否则是数字. 更详细的定义请参考 java.text.SimpleDateFormat JavaDoc。

Letter    Description        Examples
y        Year                2015
M        Month in year        Nov, 11, 7
d        Day in month        1-31
E        Day name in week    Friday, Sunday
a        Am/pm marker        AM, PM
H        Hour in day            0-23
h        Hour in am/pm        1-12
m        Minute in hour        0-60
s        Second in minute    0-60
    

1. Date = 7-Nov-2015

    SimpleDateFormat formatter = new SimpleDateFormat("dd-MMM-yyyy");
    String dateInString = "7-Nov-2015";

    try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatter.format(date));

    } catch (ParseException e) {
        e.printStackTrace();
    }

Output

Mon Nov 07 00:00:00 MYT 2015
07-Nov-2015

2. Date = 07/06/2015

    SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
    String dateInString = "07/06/2015";

    try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatter.format(date));

    } catch (ParseException e) {
        e.printStackTrace();
    }

Output
Mon Nov 07 00:00:00 MYT 2015
07/06/2015

3. Date = Nov 7, 2015

    SimpleDateFormat formatter = new SimpleDateFormat("MMM dd, yyyy");
    String dateInString = "Nov 7, 2015";        

    try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatter.format(date));

    } catch (ParseException e) {
        e.printStackTrace();
    }
Output

Mon Nov 07 00:00:00 MYT 2015
Nov 07, 2015

4. Date = Fri, Nov 7 2015

    SimpleDateFormat formatter = new SimpleDateFormat("E, MMM dd yyyy");
    String dateInString = "Fri, Nov 7 2015";        

    try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatter.format(date));

    } catch (ParseException e) {
        e.printStackTrace();
    }

Output
Mon Nov 07 00:00:00 MYT 2015
Mon, Nov 07 2015

2. Date and Time Example
1. Date and Time = Friday, Nov 7, 2015 12:10:56 PM

    SimpleDateFormat formatter = new SimpleDateFormat("EEEE, MMM dd, yyyy HH:mm:ss a");
    String dateInString = "Friday, Nov 7, 2015 12:10:56 PM";        

    try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatter.format(date));

    } catch (ParseException e) {
        e.printStackTrace();
    }

Output
Mon Nov 07 12:10:56 MYT 2015
Monday, Nov 07, 2015 12:10:56 PM

总结
本文简单的总结了将字符串转换为Java对象的主流方法，希望对大家有所帮助。