If you are using Axis client to access a webservice and using log4j for logging, you can enable printing of the http request and response contents by setting the "httpclient.wire.content" property to "debug". For example if using the log4j.properties file set the following property:
If the webservice is connecting to a secure url using https protocol, setting the java system property "javax.net.debug" to "plaintext" will provide a hex dump of the content send and received.
If you are using the web service proxy provided by oc4j within jdeveloper or the oc4j container, you can enable the java logging property "oracle.webservices.client" in logging.properties file to FINE
Setting this option will allow a standalone client to log the request and response content to the log file specified by the logging.properties file.
If the client is running within the oc4j container, you can enable the oracle diagnostics logging for "oracle.webservices.client". This can be done by navigating to the <oc4j container> -> Administration --> Logger Configuration page and setting the log level as "FINE" for "oracle.webservices.client" property.
You can view the request and response contents in the log.xml file.