基本类型的转换如：int,double,long,string,Date,Calendar之间的转换

基本类型的转换intdoublelongdate与string之间的转换 

1、int转换成String

   int i = 123;

   String str = String.valueOf(i);

2、String转换成int

   String str = "123";

   int i = Integer.valueOf(str);或者Integer.parseInt(str);

3、double转换成String

   double d = 123.0d;

   String str = String.valueOf(d);

4、String转换成double

   String str = "123";

   double d = Double.valueOf(str);

3、long转换成String

   long l = 123.0l;

   String str = String.valueOf(l);

4、String转换成double

   String str = "123";

   long l = Double.valueOf(str);

5.Calendar 转化 String

Calendar calendat = Calendar.getInstance();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

String dateStr = sdf.format(calendar.getTime());

6.String 转化Calendar

String str="2013-07-31";

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date date =sdf.parse(str);

Calendar calendar = Calendar.getInstance();

calendar.setTime(date);

7.Date 转化String

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

String dateStr=sdf.format(new Date());

8.String 转化Date

String str="2013-07-31";

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date date= sdf.parse(str);

9.Date 转化Calendar

Calendar calendar = Calendar.getInstance();

calendar.setTime(new java.util.Date());

10.Calendar转化Date

Calendar calendar = Calendar.getInstance();

java.util.Date date =calendar.getTime();