1.Calendar 转化 String
//获取当前时间的具体情况,如年,月,日,week,date,分,秒等
Calendar calendat = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String dateStr = sdf.format(calendar.getTime());
2.String 转化Calendar
String str="2010-5-27";
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date =sdf.parse(str);
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
3.Date 转化String
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
String dateStr=sdf.format(new Date());
4.String 转化Date
String str="2010-5-27";
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date birthday = sdf.parse(str);
5.Date 转化Calendar
Calendar calendar = Calendar.getInstance();
calendar.setTime(new java.util.Date());
6.Calendar转化Date
Calendar calendar = Calendar.getInstance();
java.util.Date date =calendar.getTime();
下面有个例子，插入oralce表类型为DATE的数据
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd HHmmss");
String date = sdf.format(new Date());
-----------------------------------------
String sql = "Insert into SM_SEND (*****************) " +
"values (*******************************
"',1," + "to_date('" +date+ "','YYYY-MM-DD HH24:MI:SS')" +
"," + "to_date('" +date+ "','YYYY-MM-DD HH24:MI:SS')" +
",0,null,null,null,null,null,null,null)";
