JDBC database connection tool and Access database connection example

1. When JDBC is connected to each database, there are many identical code parts. Write these parts separately in a class, connect to a specific database based on input parameters such as driver, URL, user, and password. The tool class code is as follows:

Package mine. util. database; import Java. SQL. connection; import Java. SQL. drivermanager; import Java. SQL. sqlexception; import Java. SQL. statement;/*** this tool class is used for database connection. A statement object is returned, you can execute an SQL statement to obtain the result */public class databaseconnection {public static final string access_driver = "Sun. JDBC. ODBC. jdbcodbcdriver "; public static final string mysql_driver =" com. mySQL. JDBC. driver "; public static final string marshl E_driver = "oracle. JDBC. driver. oracledriver "; public static final string sqlserver_driver =" com. microsoft. sqlserver. JDBC. sqlserverdriver "; private statement ST = NULL; private connection = NULL; public statement getstatement (string driver, string URL, string user, string password) {try {// 1. Load the driver class. forname (driver); // 2. Establish a connection through the URL and connect to the database connection = drivermanager. getconnection (URL, user, Password); // 3. Create a statement. The connection can be seen in the statement, and the statement can be seen in the cable car ST = connection. createstatement ();} catch (classnotfoundexception e) {e. printstacktrace ();} catch (sqlexception e) {e. printstacktrace ();} return st;} public void close () {try {If (st! = NULL) ST. Close (); If (connection! = NULL) connection. Close () ;}catch (sqlexception e) {e. printstacktrace ();}}}

 

2, the following using the JDBC-ODBC Bridge Connection Access database to test this tool class

 

First, configure the ODBC source as follows:

 

 

 

The St table information in the data source student. mdb is as follows:

 

The Code is as follows:

 

Package demo. database; import Java. SQL. resultset; import Java. SQL. sqlexception; import Java. SQL. statement; import mine. util. database. databaseconnection;/** use the tool databaseconnection to connect to the ACCESS database example */public class accessdemo {public void connect () {databaseconnection dbconn = new databaseconnection (); // return the statement object statement ST = dbconn. getstatement (databaseconnection. access_driver, "JDBC: ODBC: Access", "", ""); resultset rs = NULL; try {// execute the SQL statement rs = st.exe cutequery ("select * from St"); // obtain the information in the result set while (RS. next () {// note that Rs currently points to null. You must first move next () to point to the first record system. out. println (RS. getstring ("Sno") + "" + Rs. getstring ("sname") + "" + Rs. getstring ("ssex") + "" + Rs. getint ("Sage") + "" + Rs. getstring ("sdept");} Rs. close ();} catch (sqlexception e) {e. printstacktrace ();} dbconn. close ();} public static void main (string [] ARGs) {New accessdemo (). connect ();}}

 

Running result:

Test Complete

 

3. Common Database URLs

 

4. Database Data Types and corresponding Java Data Types