Java数据类型中String、Integer、int相互间的转换

Integer i = new Integer(10); 
int k = i.intValue();
即Integer.intValue();

int i = 10;
Integer it = new Integer(i);

String str = "10";  
Integer it = new Interger(str);  
int i = it.intValue();  
即：int i = Integer.intValue(string);

int i = 10;
(1)String s = String.valueOf(i);
(2)String s = Ingeger.toString(i);
(3)String s = "" + i;

String str = "10";
Integer it = Integer.valueOf(str);

Integer it = new Integer(10);
String str = it.toString();

Calendar calendar = Calendar.getInstance();
int year = calendar.get(Calendar.YEAR);
int month = calendar.get(Calendar.MONTH)+1;
int day = calendar.get(Calendar.DATE);
//获取今天的日期字符串
String today = java.text.DateFormat.getDateInstance().format(new java.util.Date());
//获取今天的日期
new java.sql.Date(System.currentTimeMillis());