JDBC-Establish a database connection

 

 

 

The username, password, and connection URL of the database can be stored in an independent file when JDBC is used to establish a database connection. For example:

Put the property file in the directory/test. Its content is:

1. Drivers = com. Microsoft. JDBC. sqlserver. sqlserverdriver
2. Url = JDBC: Microsoft: sqlserver: // localhost: 1433; databasename = studentmanager
3. User = sa
4. Password = wang411dong516

Dbconnection. Java:

 

1. /**
2. * Load the database driver through the attribute file to establish a database connection
3. */
5. Import java. SQL. sqlexception;
6. Import java. SQL. connection;
7. Import java. SQL. drivermanager;
8. Import java. util. properties;
9. Import java. Io. fileinputstream;
10. Import java. Io. ioexception;
11. Import java. Io. filenotfoundexception;
13. Public class dbconnection
14. {
15. Private string URL; // Database URL
16. Private string username; // The username used to log on to the database.
17. Private string password; // User Password
18. /**
19. * Return a connection to the database. In a system or class, database operations are often performed.
20. * The database connection is used as a separate method.
21. */
22. Public connection getconnection ()
23. {
24. Getproperty ();
25. Connection con = NULL;
26. Try
27. {
28. Con = drivermanager. getconnection (URL, username, password );
29. }
30. Catch (sqlexception E)
31. {
32. E. printstacktrace ();
33. }
34. Return con;
35. }
36. /**
37. * Read the property configuration file
38. */
39. Private void getproperty ()
40. {
41. Properties prop = new properties ();
42. Try
43. {
44. Fileinputstream in = new fileinputstream ("driver. properties ");
45. Prop. Load (in );
46. String driver = prop. getproperty ("drivers ");
47. If (driver! = NULL)
48. System. setproperty ("JDBC. Drivers", driver );
49. Url = prop. getproperty ("url ");
50. Username = prop. getproperty ("user ");
51. Password = prop. getproperty ("password ");
52. }
53. Catch (filenotfoundexception E)
54. {
55. E. printstacktrace ();
56. }
57. Catch (ioexception E)
58. {
59. E. printstacktrace ();
60. }
61. }
62. }