import    java.text.SimpleDateFormat;    

SimpleDateFormat    formatter    =   new    SimpleDateFormat    ("yyyy年MM月dd日    HH:mm:ss     ");    
Date    curDate    =   new    Date(System.currentTimeMillis());//獲取當前時間    
String    str    =    formatter.format(curDate);    

SimpleDateFormat    sDateFormat    =   new    SimpleDateFormat("yyyy-MM-dd    hh:mm:ss");    
String    date    =    sDateFormat.format(new    java.util.Date()); 

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM"); 
String date=sdf.format(new java.util.Date()); 

df=DateFormat.getDateTimeInstance(DateFormat.FULL,DateFormat.FULL,Locale.CHINA);
System.out.println(df.format(new Date()));

 ContentResolver cv = this.getContentResolver();
        String strTimeFormat = android.provider.Settings.System.getString(cv,
                                           android.provider.Settings.System.TIME_12_24);

        if(strTimeFormat.equals("24"))
       {
               Log.i("activity","24");
        }

Calendar c = Calendar.getInstance();
取得系統日期:year = c.get(Calendar.YEAR)
               month = c.grt(Calendar.MONTH)
               day = c.get(Calendar.DAY_OF_MONTH)
取得系統時間：hour = c.get(Calendar.HOUR_OF_DAY);
                  minute = c.get(Calendar.MINUTE)

Calendar c = Calendar.getInstance();
取得系統日期:year = c.get(Calendar.YEAR)
               month = c.grt(Calendar.MONTH)
               day = c.get(Calendar.DAY_OF_MONTH)
取得系統時間：hour = c.get(Calendar.HOUR_OF_DAY);
                  minute = c.get(Calendar.MINUTE)
                    Calendar c = Calendar.getInstance();
取得系統日期:year = c.get(Calendar.YEAR)
                   month = c.grt(Calendar.MONTH)
                   day = c.get(Calendar.DAY_OF_MONTH)
取得系統時間：hour = c.get(Calendar.HOUR_OF_DAY);
                     minute = c.get(Calendar.MINUTE)

Time t=new Time(); // or Time t=new Time("GMT+8"); 加上Time Zone資料。
t.setToNow(); // 取得系統時間。
int year = t.year;
int month = t.month;
int date = t.monthDay;
int hour = t.hour; // 0-23
int minute = t.minute;
int second = t.second;