I am able to do the web service connection...
I added the key store using the command:
keytool -import -trustcacerts -file <file path/filename.cer> -alias <aliasName> -keystore <JAVA_HOME/jre/lib/security/cacerts>
gave the password as "changeit" and added the certificate in keystore.
Now in code i added two lines:
System.setProperty("javax.net.ssl.trustStore", "<JAVA_HOME>/jre/lib/security/cacerts");
System.setProperty("javax.net.ssl.trustStorePassword", "changeit");
also added
_call.setUsername("username");
_call.setPassword("password");
where _call is the call object of Call Class.
And it worked!!!!!!