gistfile1.java

import javax.validation.constraints.Max;
import javax.validation.constraints.Min;
import javax.validation.constraints.Pattern;
import javax.validation.constraints.Size;

@Configuration
public class MysqlXADataSource {
  @Property(desc = "User name to use for connection authentication.")
  @Size(min = 6, max = 255)
  private String user = ""; // default value - hence optional property

  @Property(desc = "Password to use for connection authentication.")
  @Size(min = 6, max = 255)
  private String password = ""; // default value - hence optional property

  @Property(desc = "A JDBC URL.")
  @Pattern(regexp = "([a-zA-Z]{3,})://([\w-]+\.)+[\w-]+(/[\w- ./?*)?")
  private URL url; // required property

  @Property(desc = "Port number where a server is listening for requests.")
  @Min(0)
  @Max(65535)
  private Integer portNumber = 1521; // default value - hence optional property

  @Resource
  private List<ConfigurableItem> items; // configuration childs 
}

@Stateless
public class SessionBean {
  @Resource(name = "jdbc/mysql-ds")
  private DataSource ds;
}