Using JDBC with Firewalls

from Oracle® Database JDBC Developer's Guide and Reference

http://docs.oracle.com/cd/B19306_01/java.102/b14355/apxtblsh.htm#CHDBBDDA

Firewall timeout for idle-connections may sever a connection. This can cause JDBC applications to hang while waiting for a connection. You can perform one or more of the following actions to avoid connections from being severed due to firewall timeout:

• If you are using connection caching or connection pooling, then always set the inactivity timeout value on the connection cache to be shorter than the firewall idle timeout value.
• Pass oracle.net.READ_TIMEOUT as connection property to enable read timeout on socket. The timeout value is in milliseconds.
• For both JDBC OCI and JDBC Thin drivers, use net descriptor to connect to the database and specify the ENABLE=BROKEN parameter in the DESCRIPTIONclause in the connect descriptor. Also, set a lower value for tcp_keepalive_interval.
• Enable Oracle Net DCD by setting SQLNET.EXPIRE_TIME=1 in the sqlnet.ora file on the server-side.

Oracle JDBC Connection Test

Save source  file: Conn.java

import java.sql.*;
class Conn {
  public static void main (String[] args) throws Exception
  {
   Class.forName ("oracle.jdbc.OracleDriver");

   Connection conn = DriverManager.getConnection
     ("jdbc:oracle:thin:@localhost:1521:ORCL","scott","tiger");
   try {
     Statement stmt = conn.createStatement();
     try {
       ResultSet rset = stmt.executeQuery("select BANNER from SYS.V_$VERSION");
       try {
         while (rset.next())
           System.out.println (rset.getString(1));   // Print col 1
       } 
       finally {
          try { rset.close(); } catch (Exception ignore) {}
       }
     } 
     finally {
       try { stmt.close(); } catch (Exception ignore) {}
     }
   } 
   finally {
     try { conn.close(); } catch (Exception ignore) {}
   }
  }
}

ps: Change host, port, SID, user and password to your value in connection url

("jdbc:oracle:thin:@localhost:1521:ORCL","scott","tiger");

Compile java

javac -cp .:$ORACLE_HOME/jdbc/lib/ojdbc5.jar:$ORACLE_HOME/jlib/orai18n.jar Conn.java

Run program

java -cp .:$ORACLE_HOME/jdbc/lib/ojdbc5.jar:$ORACLE_HOME/jlib/orai18n.jar Conn



PS : for compile and run in windows os, change columns(:) to semicolons(;)  like
.;$ORACLE_HOME/jdbc/lib/ojdbc5.jar;$ORACLE_HOME/jlib/orai18n.jar

also change jar names in their directories the correct ones.

simple java tricks

http://www.oracle.com/technetwork/java/compile-136656.html