Using cl_http_client for calling WSDL(URL) method

Hi Experts,

I am trying to consume WSDL using  class CL_HTTP_CLIENT, may be I am missing some thing in below code, could any one please correct what I am missing? , I am not pretty sure how to use methods but written below code for reference written using other codes in SDN

Actually I need to pass multiple parameters to SubmitEx2 method at a time,

is there any best example with WSDL and code for regarding methods to use while calling URL and parameters to pass...,

like any WSDL in http://www.webservicex.net like Currency Convertor     

my code for your information :

DATA: http_client TYPE REF TO if_http_client,
host_str TYPE string VALUE 'X.y.z.a,
    service_str TYPE string,
    path TYPE string VALUE 'itpserver/itpserver.asmx',
    errortext TYPE string. "used for error handlingDATA  : wf_string1 TYPE string,

         lw_input TYPE zcrm_aia_wsdl_cpsubmit_ex2soa1,
         lw_output TYPE  zcrm_aia_wsdl_cpsubmit_ex2soap,

         lw_inputs TYPE string,
         lw_outputs TYPE  string.

*CALL METHOD cl_http_client=>create

*  EXPORTING

*    host               = host_str

*   service            = service_str

**   proxy_host         = proxy_host

**   proxy_service      = proxy_service

**   scheme             = '1'"scheme

*  IMPORTING

*    client             = http_client

*  EXCEPTIONS

*    argument_not_found = 1*    internal_error     = 2*    plugin_not_active  = 3*    OTHERS             = 4.

CALL METHOD cl_http_client=>create_by_url
  EXPORTING
    url                = 'http://x.y.z.a/itpserver/itpserver.asmx'

*   proxy_host         =

*   proxy_service      =

*   ssl_id             =*   sap_username       =*   sap_client         =
  IMPORTING
    client             = http_client
  EXCEPTIONS
    argument_not_found = 1
    plugin_not_active  = 2
    internal_error     = 3
    OTHERS             = 4.IF sy-subrc <> 0.
  MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
             WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
ENDIF.

CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = '~request_method'
    value = 'POST'.CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = '~server_protocol'
    value = 'HTTP/1.1'.CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = '~request_uri'
    value = '/itpserver/itpserver.asmx'.

CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = 'Content-Type'
    value = 'application/soap+xml; charset=utf-8'."'text/xml; charset=utf-8'.

CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = 'Content-Length'
    value = '19000'."txlen.CALL METHOD http_client->request->set_header_field
  EXPORTING
    name  = 'SOAPAction'
    value = 'http://www.aia-itp.com/itpserver/wsdl/SubmitEx2'.

CONCATENATE'<?xml version="1.0" encoding="utf-8"?>''<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"''xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">'
' <soap:Body>'
    '<service xmlns="http://www.aia-itp.com/itpserver/wsdl">generatedocument</service>'
    '<parms xmlns="http://www.aia-itp.com/itpserver/wsdl">'
      '<string>Quote</string>'
      '<string></string>'
    '</parms>'
    '<inKeyValues xmlns="http://www.aia-itp.com/itpserver/wsdl">'
      '<KeyValue>'
        '<key></key>'
        '<value></value>'
      '</KeyValue>'
      '<KeyValue>'
        '<key></key>'
        '<value></value>'
      '</KeyValue>'
    '</inKeyValues>'
    '<inDocuments xmlns="http://www.aia-itp.com/itpserver/wsdl">'
      '<Doc>'
        '<id>xmldoc</id>'
        '<content></content>'
      '</Doc>'
      '<Doc>'
        '<id>xmldoc</id>'
        '<content></content>'
      '</Doc>'
    '</inDocuments>'
    '<sessionID xmlns="http://www.aia-itp.com/itpserver/wsdl"></sessionID>'
    '<jobID xmlns="http://www.aia-itp.com/itpserver/wsdl"></jobID>''</soap:Body>''</soap:Envelope>'
INTO wf_string1.
CALL METHOD http_client->request->set_cdata
  EXPORTING
    data   = wf_string1*   offset = 0
    length = '19000'.

CALL METHOD http_client->send
  EXCEPTIONS
    http_communication_failure = 1
    http_invalid_state         = 2.

C

ALL METHOD http_client->receive
  EXCEPTIONS
    http_communication_failure = 1
    http_invalid_state         = 2
    http_processing_failed     = 3.CLEAR wf_string1 .

wf_string1 = http_client->response->get_cdata( ).  

Thanks,

VijInd