Problem in connecting to database

I am completely new user to jdbc.
I am working on Informix Dynamic Server Version 7.31.UC2A database server. I am just trying to connect to the database using the following url.

jdbc:informix-direct:// testDB:INFORMIXSERVER=iin_online

When I run the program the following error is returned.

ERROR : Failed to connect to database Can't load driver java.lang.ClassNotFoundE
xception: com.informix.jdbc.IfxDirectConnection
java.sql.SQLException: Can't load driver java.lang.ClassNotFoundException: com.i
nformix.jdbc.IfxDirectConnection
at java.lang.Throwable.fillInStackTrace(Native Method)
at java.lang.Throwable.fillInStackTrace(Compiled Code)
at java.lang.Throwable.<init>(Compiled Code)
at java.lang.Exception.<init>(Exception.java:42)
at java.sql.SQLException.<init>(SQLException.java:43)
at com.informix.util.IfxErrMsg.getLocSQLException(IfxErrMsg.java:447)
at com.informix.jdbc.IfxDriver.connect(Compiled Code)
at java.sql.DriverManager.getConnection(Compiled Code)
at java.sql.DriverManager.getConnection(DriverManager.java:137)
at jdbcTest.main(jdbcTest.java:24)

And the class file IfxDirectConnection is not in the library path. I am not able to understand why is it asking for that class.
Is this the proper way to get connected to the database when I run my application on the same machine where the database server is running. I would appreciate if sombody can help me in this.

Regards
sachi

Sachidananda Karkala
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