Beginner JDBC,JDBC Simple Package for tool class

Tool classes do not need to be inherited

Public final class jdbcutils{

Encapsulates database connection parameters for late change of parameter values

private static String url= "JDBC:MYSQL://LOCALHOST:3306/JDBC";

private static String user= "UserName";

private static String password= "password";

No objects to be created

Private Jdbcutils () {}

Static code block: Executes at project start time

static{

try{

Class.forName ("Com.mysql.jdbc.Driver");

}catch (ClassNotFoundException e) {

throw new Ininitializererror (e);

}

}

Create a database connection

public static Connection Getconnetcion () throws sqlexception{

Return drivaermanager.getconnetcion (Url,user,password);

}

Freeing resources

public static void FreeResource (ResultSet resultset,statement statement,connection conn) {

try{

if (resultset!=null)

Resultset.close ();

}catch (SQLException e) {

E.printstacktrace ();

}finally{

try{

if (statement!=null)

Statement.close ();

}catch (SQLException e) {

E.printstacktrace ();

}finally{

try{

if (conn!=null)

Conn.close ();

}catch (SQLException e) {

E.printstacktrace ();

}

}

}

}

}

Example

public class userdao{

public static void Testgetusers () throws exception{

Connection Conn=null;

Statement Statement=null;

ResultSet Resultset=null;

try{

Conn=jdbcutils.getconnetcion ();

Statement=conn.createstatement ();

Resultset=statement.excutequery ("SELECT * from user");

while (Resultset.next ()) {

System.out.println (Resultset.getobject (1) + "\ T" +resultset.getobject (2));

}

}finally{

Jdbcutils.freeresource (Resultset,statement,conn);

}

}

}

Beginner JDBC,JDBC Simple Package for tool class