How to get connection in java class from datasource to execute sql

[valatharv]

Hi,

I need to do some validation from database table using regular expression in query, which I cannot do using entity query directly, can it be done using entity query directly ?
example : select upper(regexp_replace(ITEM_NAME, '\\W', '')) from ITEM_TABLE

I have a class which works fine with-in seam, but I need suggestion on how to get connection details from persistence/xxx-ds.xml instead of hardcoding as in code below.

Please suggest if there is any better way around

Code:
-----
public class ValidateUtil {
     Statement st = null;
     public ValidateUtil() throws Exception {
          Class.forName("oracle.jdbc.OracleDriver");
          System.out.println("Driver Loaded.");
          String url = "jdbc:oracle:thin:@<host>:1521/<SID>";

          Connection conn = DriverManager.getConnection(url, "<user>", "<pwd>");
          System.out.println("Got Connection.");
          st = conn.createStatement();
     }

     public void executeSQLCommand(String sql) throws Exception {
          st.executeUpdate(sql);
     }
     
     public boolean checkData(String sql, String strCompare) throws Exception {
          
          ResultSet rs = st.executeQuery(sql);
          ResultSetMetaData metadata = rs.getMetaData();
          
          boolean boolDup = false;
          while (rs.next()) {
               for (int i = 0; i < metadata.getColumnCount(); i++) {
                    Object value = rs.getObject(i + 1);     
                    ......
                         if (value.toString().trim().equalsIgnoreCase(strCompare)) {
                              boolDup = true;
                         }
               ....
          }     
          return (boolDup);
     }
}

[salski22]

You probably have persistance.xml that pints to your xxx-ds. In persistance.xml you should have persistance-unit name something like

<persistence-unit name="dsname">

then in your class you point to your EntityManager

public class ValidateUtil 
{
      private EntityManager dsname;

     //and something like that

     Query q = dsname.createQuery("select * from ....")
     ....
}

[blabno]

From POJO use JNDI. From EJB use @Resource to inject datasource i.e.:

@Resource(mappedName="java:/DefaultDS") DataSource dataSource;