Problems when enabling gzip compression

I am having problems when enabling the request/response compression
mode. I am using xmlrpc-3.0a1.jar for both my client and my server. In
the client I run the following:

config = new XmlRpcClientConfigImpl();
config.setServerURL(serverURL);
// enables faster and memory saving streaming mode
config.setContentLengthOptional(true);
// enable vendor extensions to allow compression, data types support ...
config.setEnabledForExtensions(true);
config.setGzipCompressing(true); // requests gzip compression
config.setGzipRequesting(true); // requests server to gzip response

client = new XmlRpcClient();
client.setConfig(config);
client.execute(...)
[...]

In the server I make use of the XmlRpcServlet class
(org.apache.xmlrpc.webserver package) embedded into Tomcat 5 and I have
set enabledForExtensions to true within the init parameters of the
servlet (web.xml file)

When I run a dummy request as it is described in the code above I get
the following exception:

org.apache.xmlrpc.XmlRpcException: Failed to parse XML-RPC request:
Content is not allowed in prolog.
at org.apache.xmlrpc.client.XmlRpcStreamTransport.readResponse
(XmlRpcStreamTransport.java:274)
at org.apache.xmlrpc.client.XmlRpcStreamTransport.sendRequest
(XmlRpcStreamTransport.java:216)
at org.apache.xmlrpc.client.XmlRpcClientWorker.execute
(XmlRpcClientWorker.java:53)
at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:166)
at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:136)
at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:125)
at esavo.voql.xmlrpc.MyXmlRpcClient.execute(MyXmlRpcClient.java:54)
at esavo.voql.xmlrpc.MyXmlRpcClient.main(MyXmlRpcClient.java:74)

If I comment the gzip compression out, both on the request and the
response, my test works fine:

config = new XmlRpcClientConfigImpl();
config.setServerURL(serverURL);
// enables faster and memory saving streaming mode
config.setContentLengthOptional(true);
// enable vendor extensions to allow compression, data types support ...
config.setEnabledForExtensions(true);

client = new XmlRpcClient();
client.setConfig(config);
client.execute(...)
[...]

The complete source code is the following:

1. Client Side
-------------------------
package esavo.voql.xmlrpc;

import java.net.URL;
import org.apache.xmlrpc.*;
import org.apache.xmlrpc.client.*;

/**

• MyXmlRpcClient
• @author Inaki Ortiz de Landaluce Saiz - ESAC/ESA - Madrid, Spain
  */
  public class MyXmlRpcClient {

/** XMLRpcClientConfig instance to specify serverURL, credentials ...etc */
private XmlRpcClientConfigImpl config;

/** The XmlRpcClient itself */
private XmlRpcClient client;

/**

• Creates a new instance of MyXmlRpcClient
  */
  public MyXmlRpcClient(URL serverURL) { // Step 1: Instances the client configuration and sets some properties // N.B: This should be configurable through a xml or properties file config = new XmlRpcClientConfigImpl(); config.setServerURL(serverURL); // enables faster and memory saving streaming mode config.setContentLengthOptional(true); // enable vendor extensions to allow compression, data types support ... config.setEnabledForExtensions(true); // it works fine when the following two lines are commented config.setGzipCompressing(true); // requests gzip compression config.setGzipRequesting(true); // requests server to gzip response // Step 2: Instances the client and atttaches the configuration to it client = new XmlRpcClient(); client.setConfig(config); // sets the fastest transport factory. // There are several transport factories available: // XmlRpcSunHttpTransportFactory - Uses default HTTP connection // XmlRpcCommonsTransportFactory - Jakarta commons, lower memory profile // XmlRpcLiteHttpTransportFactory - Faster, does not support HTTP/1.1</ul> client.setTransportFactory(new XmlRpcLiteHttpTransportFactory(client)); }

/**

• Executes an XML-RPC call
• @param methodName The method being performed.
• @param method The parameters.
• @return The result object
  */
  public Object execute(String methodName, Object[] params) throws XmlRpcException { return client.execute(methodName, params); }

/**

• Returns XmlRpcClient instance
  */
  public XmlRpcClient getClient() { return client; }

public static void main(String[] args) {
String serverStr = "http://localhost:8084/VOQL-server/servlet/xmlrpc";
try {
URL serverURL = new URL(serverStr);
MyXmlRpcClient client = new MyXmlRpcClient(serverURL);

// full check disabled
Object[] params = new Object[]

{new Boolean(false)}

;
Boolean result = (Boolean) client.execute("Status.check", params);
System.out.println("Result is " + result.toString());
} catch (XmlRpcClientException e)

{ e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); }

}
}

2. Server Side
--------------------------

2.1 WAR configuration file (web.xml)
-------------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<servlet>
<servlet-name>XmlRpcServlet</servlet-name>
<servlet-class>org.apache.xmlrpc.webserver.XmlRpcServlet</servlet-class>
<init-param>
<param-name>enabledForExtensions</param-name>
<param-value>true</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>XmlRpcServlet</servlet-name>
<url-pattern>/servlet/xmlrpc</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>
index.jsp
</welcome-file>
</welcome-file-list>
</web-app>

2.2 Handler
-----------------------
package esavo.voql.server;

/**
*

• @author Inaki Ortiz de Landaluce Saiz - ESAC/ESA - Madrid, Spain
  */
  public class Status {

/** Creates a new instance of Status */
public Status() {
}

public boolean check(boolean fullCheck)

{ // perform a full check on service availability. TBD if(!fullCheck) return true; else return false; }

}

2.3 XmlRpcServlet.properties
----------------------------------------------------
Remote=org.apache.xmlrpc.test.BaseTest$Remote
Status=esavo.voql.server.Status