String轉換成日期格式String

把形如”20150323102222”的String字符串，轉換成“2015-03-23 10:22:22”的字符串

用到SimpleDateFormat

String a = "20150323102222";
SimpleDateFormat df = new SimpleDateFormat("yyyyMMddhhmmss");
Date date = df.parse(a);

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
String b = sdf.format(date);
system.out.println(b);