errors when trying to connect to database

[matpj]

Hi all,

I am trying to connect to a database within a class:

import java.sql.*;

class SimpleOraJava {
  public static void main(String args[]) throws SQLException {
    DriverManager.registerDriver(
      new oracle.jdbc.driver.OracleDriver()
    );
    String serverName = "nikuuat";
    int port = 1521;
    String user = "niku";
    String password = "niku";
    String SID = "nikuuat";
    String URL = "jdbc:oracle:thin:@" + serverName + ":" + port + ":" + SID;
    Connection conn = DriverManager.getConnection(URL, user, password);
    String SQL = "SELECT DSTI_PROJ_REF FROM NIKU.ODF_CA_PROJECT";
    Statement stat = conn.createStatement();
    ResultSet rs = stat.executeQuery(SQL);
    while (rs.next()) {
      System.out.println(
        rs.getInt(1) +
        "\t" +
        rs.getString(2)
      );
    }
    stat.close();
    conn.close();
  }
}

when I try to run this I get the following error:

run:
Exception in thread "main" java.sql.SQLException: Io exception: The Network Adapter could not establish the connection
        at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
        at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:179)
        at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:334)
        at oracle.jdbc.ttc7.TTC7Protocol.handleIOException(TTC7Protocol.java:3695)
        at oracle.jdbc.ttc7.TTC7Protocol.logon(TTC7Protocol.java:352)
        at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:362)
        at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:536)
        at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:328)
        at java.sql.DriverManager.getConnection(DriverManager.java:582)
        at java.sql.DriverManager.getConnection(DriverManager.java:185)
        at SimpleOraJava.main(SimpleOraJava.java:30)
Java Result: 1
BUILD SUCCESSFUL (total time: 2 seconds)

i'm not sure what to do, can anybody advise?

thanks in advance,
Matt

[matpj]

can anyone help me?

[neilcoffey]

Not too familiar with Oracle or this particular JDBC driver, but if I was coming at this new, I would:
- double tripple check the URL format -- I know they're different drivers and the format isn't standard, but compared to the format for connecting to MySQL or connecting to SQL Server, the format you have above looks quite odd
- does your DB log anything useful? (like a "permission denied to client XXX" message)
- can you connect from the same machine to the DB but via a different means, e.g. an interactive SQL client?
- is Java even getting as far as sending anything down the network? - if the DB is on a different box, install a packet sniffer and check that some data is actually being sent across the network and some coming back in? if something is going out but not coming back in, what does a packet sniffer on the DB machine pick up? any firewall in the way of the two that you should be aware of?