Java：String和Date、Timestamp之间的转换

 1 package Test;
 2 
 3 import java.sql.Timestamp;
 4 import java.text.DateFormat;
 5 import java.text.SimpleDateFormat;
 6 import java.util.Date;
 7 
 8 public class Test1 {
 9     public static void main(String[] args) {
10         Test1 t1=new Test1();
11         t1.action1();
12         t1.action2();
13         t1.action3();
14         t1.action4();
15         t1.action5();
16         t1.action6();
17         
18     }
19     
20     // String -> Date
21     public void action1(){
22         String dateStr = "2010/05/04 12:34:23";
23         Date date = new Date();
24         //注意format的格式要与日期String的格式相匹配
25         DateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
26         try {
27             date = sdf.parse(dateStr);
28             System.out.println(date.toString());
29         } catch (Exception e) {
30             e.printStackTrace();
31         }
32     }
33     //  Date -> String 日期向字符串转换，可以设置任意的转换格式format
34         public void action2(){
35             String dateStr = "";
36             Date date = new Date();
37             //format的格式可以任意
38             DateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
39             DateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd HH/mm/ss");
40             try {
41                 dateStr = sdf.format(date);
42                 System.out.println(dateStr);
43                 dateStr = sdf2.format(date);
44                 System.out.println(dateStr);
45             } catch (Exception e) {
46                 e.printStackTrace();
47             }
48         }
49         
50     //  String ->Timestamp  注：String的类型必须形如： yyyy-mm-dd hh:mm:ss[.f...] 这样的格式，中括号表示可选，否则报错！！！
51             public void action3(){
52                 Timestamp ts = new Timestamp(System.currentTimeMillis());
53                 String tsStr = "2011-05-09 11:49:45";
54                 try {
55                     ts = Timestamp.valueOf(tsStr);
56                     System.out.println(ts);
57                 } catch (Exception e) {
58                     e.printStackTrace();
59                 }
60             }
61             
62         //  Timestamp -> String 使用Timestamp的toString()方法或者借用DateFormat
63                     public void action4(){
64                         Timestamp ts = new Timestamp(System.currentTimeMillis());
65                         String tsStr = "";
66                         DateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
67                         try {
68                             //方法一
69                             tsStr = sdf.format(ts);
70                             System.out.println(tsStr);
71                             //方法二
72                             tsStr = ts.toString();
73                             System.out.println(tsStr);
74                         } catch (Exception e) {
75                             e.printStackTrace();
76                         }
77                     }
78                 //  Timestamp -> Date
79                     public void action5(){
80                         Timestamp ts = new Timestamp(System.currentTimeMillis());
81                         Date date = new Date();
82                         try {
83                             date = ts;
84                             System.out.println(date);
85                         } catch (Exception e) {
86                             e.printStackTrace();
87                         }
88                     }
89                 //  Date -> Timestamp
90                     public void action6(){
91                         Date time = new Date();
92                         Timestamp dateTime = new Timestamp(time.getTime());
93                         System.out.println(dateTime);
94                     }
95 }