Java Database Connectivity
part 10/17 · 28.8 KB total
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If a database operation fails, JDBC raises an SQLException. There is typically very little one can do to recover from such an error, apart from logging it with as much detail as possible. It is recommended that the SQLException be translated into an application domain exception (an unchecked one) that eventually results in a transaction rollback and a notification to the user.
The following code is an example of a database transaction:
boolean autoCommitDefault = conn.getAutoCommit();
try {
conn.setAutoCommit(false);
/* You execute statements against conn here transactionally */
conn.commit();
} catch (Throwable e) {
try { conn.rollback(); } catch (Throwable e) { logger.warn("Could not rollback transaction", e); }
throw e;
} finally {
try { conn.setAutoCommit(autoCommitDefault); } catch (Throwable e) { logger.warn("Could not restore AutoCommit setting",e); }
}
For an example of a CallableStatement (to call stored procedures in the database), see the JDBC API Guide documentation.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
public class Mydb1 {
static String URL = "jdbc:mysql://localhost/mydb";
public static void main(String[] args) {
try {
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection(URL, "root", "root");
Statement stmt = conn.createStatement();
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