Labo SOAP

1
Labo SOAP

• Dinsdag 24 maart 2005
• Peter.Demeester_at_kahosl.be

2
References

• Java and Soap, Robert Englander, OReilly
  (0-596-00175-4)
• Programming Web Services with SOAP, James Snell,
  Doug Tidwell and Pavel Kulchenko, OReilly
  (0-596-00095-2)
• Writing a Client Application using Apache SOAP
  (http//www.xmethods.net/gettingstarted/apache.htm
  l)
• The Web services (r)evolution (http//www-106.ibm.
  com/developerworks/library/ws-peer2/)
• Making Apache SOAP Invocations using SMTP
  (http//ws.apache.org/soap/faq/faq_chawke_smtp.htm
  l)
• Setting up Apache Tomcat and a Simple Apache SOAP
  Client for SSL Communication (http//ws.apache.org
  /soap/docs/install/FAQ_Tomcat_SOAP_SSL.html)

3
Soap installation

• See http//ingenieur.kahosl.be/vakgroep/it/onderwi
  js/ModBest/soap.htm

4
First there was

• XML-RPC

5
XML-RPC?

• It's a spec and a set of implementations that
  allow software running on disparate operating
  systems, running in different environments to
  make procedure calls over the Internet. It's
  remote procedure calling using HTTP as the
  transport and XML as the encoding. XML-RPC is
  designed to be as simple as possible, while
  allowing complex data structures to be
  transmitted, processed and returned.

6
XML-RPC
7
Apache XML-RPC

• Java implementation of XML-RPC
• Client class

import org.apache.xmlrpc. XmlRpcClient xmlrpc
new XmlRpcClient("http//localhost8080/") Ve
ctor params new Vector () params.addElement
("some parameter") // this method returns a
string String result (String) xmlrpc.execute
("method.name", params)
8
Server class

• import org.apache.xmlrpc.
• WebServer webserver new WebServer(port)
• webserver.addHandler ("examples",
  someHandler)

9
Exercise

• Write handler that allows to calculate sum of two
  integers
• Write server
• Write client

10
Allowed types

• See http//ws.apache.org/xmlrpc/types.html

11
SOAP

• http//www.w3.org/TR/SOAP

12
SOAP
Service Provider
Service Requester
HTTP Server
SOAP Dispatch
?
SOAP request/response messages
Underlying implementation
13
SOAP

• SOAP as RPC (message contains a method name
  arguments) extends OO to web-based remote objects
• SOAP can also be used for exchanging documents
  containing XML data
• We will concentrate on RPC
• Through supporting web services (in SOAP)
  integration within an enterprise and with
  external business partners

14
SOAP

• Use of SOAP allows software processes to change
  without requiring changes to the other party, of
  course as long as the request and response
  message do not change
• Ex 1st implementation of service provider can be
  thin wrapper around legacy code. When the new
  code is ready the change is invisible to users of
  the service
• If a required service is not available or if
  another provider has a better price service
  requester can choose among compatible service
  offerings

15
What is SOAP?

• SOAP is a loosely coupled protocol
• Lightweight (minimal amount of overhead), simple
  (to use, not necessarily to write)
• Over HTTP SMTP, no problems with firewalls
• SOAP is a minimal set of conventions for invoking
  code using XML and HTTP
• SOAP is an Internet-friendly alternative to
  Microsoft's DCOM, Sun's RMI, and OMG's CORBA/IIOP

16
SOAP structure
SOAP Message
HTTP HEADER
Envelope
Header
XML
Body
17
SOAP envelope

• SOAP envelope is analogous to envelope of a
  letter
• Supplies info about
• Message that is being encoded in SOAP payload
• Including data relating to the sender and
  recipient
• Details about the message

18
SOAP envelope

• Header of an envelope specifies how a message
  must be processed
• Before an application goes forward with
  processing a message
• application can determine information about a
  message (including whether it will even be able
  to process the message) (SOAPAction)
• A SOAP message can also include the encoding
  style (assists the recipient in interpreting the
  message)

19
SOAP envelope request

• ltSOAP-ENVEnvelope xmlnsSOAP-ENV"http//schem
  as.xmlsoap.org/soap/envelope/
  xmlnsxsi"http//www.w3.org/1999/XMLSchema-instan
  ce xmlnsxsd"http//www.w3.org/1999/XMLSchema"
  gt ltSOAP-ENVBodygt ltns1getRate
  xmlnsns1"urndemo1exchange"
  SOAP-ENVencodingStyle
  "http//schemas.xmlsoap.org/soap/encoding/"gt ltco
  untry1 xsitype"xsdstring"gtUSAlt/country1gt ltcou
  ntry2 xsitype"xsdstring"gtjapanlt/country2gt
  lt/ns1getRategt lt/SOAP-ENVBodygt
• lt/SOAP-ENVEnvelopegt

20
SOAP envelope response

• ltSOAP-ENVEnvelope xmlnsSOAP-ENV"http//schem
  as.xmlsoap.org/soap/envelope/
  xmlnsxsi"http//www.w3.org/1999/XMLSchema-instan
  ce xmlnsxsd"http//www.w3.org/1999/XMLSchema"
  gtltSOAP-ENVBodygt ltns1getRateResponse
  xmlnsns1"urndemo1exchange" SOAP-ENV
  encodingStyle "http//schemas.xmlsoap.org/s
  oap/encoding/"gt
• ltreturn xsitype"xsdfloat"gt144.52lt/returngt lt
  /ns1getRateResponsegtlt/SOAP-ENVBodygt
• lt/SOAP-ENVEnvelopegt

21
SOAP envelope

• Encoding is specified within envelope
• Allows application to determine whether it can
  read the incoming message (using the value of the
  attribute encodingStyle)

22
Encoding

• Second major element is simple means of encoding
  user-defined data types (in theory!)
• In XML-RPC encoding can only occur for a
  predefined set of data types
• With SOAP you can use XML Schema to specify new
  data types (using complexType) and these new
  types can be easily represented in XML as part of
  a SOAP payload

23
Encoding

• Because of this integration with XML Schema
  encode any data type in a SOAP message that you
  can logically describe in XML Schema (see later)

24
SOAP Client in Apache SOAP

• Example

25
Writing a Client application

• Importing packages
• //Required due to use of URL class, required by
  Call //class
• import java.net. //Required due to use of
  Vector class import java.util. //Apache SOAP
  classes used by client import org.apache.soap.uti
  l.xml. import org.apache.soap. import
  org.apache.soap.rpc.

26
Writing a Client application

• Following line sets the default Encoding style to
  be the standard SOAP encoding
• call.setEncodingStyleURI(Constants.NS_URI_SOAP_ENC
  )
• Following line sets the Target Object URI, which
  can be thought of as the object interface
  identifier
• call.setTargetObjectURI ("urnxmltoday-airline-tic
  kets")
• The following line sets the Method Name that you
  wish to invoke on the Object Interface that you
  described in the line above
• call.setMethodName ("buyTickets")

27
Writing a Client application

• Parameter vector is setup
• Call object accepts a vector of parameters
• These parameters (each of which represents 1
  argument to the method being invoked) are
  serialized "for the wire" using a type mapping
  system that serializes based on the type of the
  object held by each parameter
• Vector params new Vector( )
• params.addElement(new Parameter("flightNumber",
  Integer.class, flightNumber, null))

28
Writing a Client application

• Now its time to invoke the method
• URL url new URL ("http//rpc.middleearth.com")
• Response resp call.invoke (url, "")
• URL object represents the SOAP endpoint that will
  be receiving the request
• The invocation may throw a SoapException if
  something goes wrong
• Make provisions to catch the exception

29
Writing a Client application

• Check the response to see if an exception was
  generated at the SOAP protocol level
• if (resp.generatedFault()) Fault
  faultresp.getFault() System.out.println("Fault
  code " fault.getFaultCode())
  System.out.println("Fault string
  fault.getFaultString())
• else
• Otherwise the call was successful and a return
  value can be retrieved.
• Parameter stores values of class Object, so
  downcast the object to expected type for further
  handling

30
Writing a Client application

• Parameter resultresp.getReturnValue()
• Object o result.getValue()

31
Invocation

• Actual invocation is represented by the Call
  object
• Allows you to set
• the target of the call,
• Method to invoke
• Encoding style
• Parameters

32
A First Fast Example of a SOAP implementation in
Java

• Purpose testing your Apache SOAP installation

33
Setting up Apache SOAP

• Open source project that support SOAP (and Java)
  
• Apache SOAP (http//xml.apache.org/soap)This
  project provides a SOAP toolkit in Java

34
Building our 1st web service

• The tools we are going to use are
• Apache SOAP 2.3.1 (http//xml.apache.org/soap)
• Apache Jakarta Tomcat 4.1.29 (http//jakarta.apach
  e.org/tomcat)
• Apache Xerces XML Parser 2.5.0 (http//xml.apache.
  org/xerces-j/index.html)
• Sun JavaMail 1.3.1(http//java.sun.com/products/j
  avamail)
• JavaBeans Activation Framework (JAF
  1.0.2)(http//java.sun.com/products/beans/glasgow
  /jaf.html)

35
Installed software

• Apache SOAP 2.3.1 open source Java
  implementation of SOAP includes support for a
  useful subset of the SOAP 1.1 specification
• Apache Jakarta Tomcat 4.1.29 open source Java
  web server implements the Java servlets 2.2 API
  specification
• Apache Xerces XML Parser 2.5.0 open source XML
  parser implements most of the latest XML
  specifications
• Sun JavaMail used for the SMTP protocol support
  included in SOAP

36
Tools and installation

• See http//ingenieur.kahosl.be/vakgroep/it/onderw
  ijs/ModBest/soap.htm

37
Starting web server

• Start the tomcat web server by entering the
  command startup or catalina run

38
Starting the web server

• This commands starts the web server on your local
  host on port 8080
• Start IE and type in the URL http//localhost8080
  /soap
• This activates the Apache Soap system that was
  installed into /soap when you edited the tomcat
  server.xml

39
Starting the webserver
40
Writing a web service

• This web service will calculate the exchange rate
  between 2 countries
• Java interface is
• public interface IExchange
• float getRate( String country1, String
  country2 )

41
Writing a web service

• Implementation of the interface
• public class Exchange implements IExchange
• public float getRate( String country1, String
  country2 )
• System.out.println( "getRate( " country1
  ", " country2 " )" )
• return 144.52F // always return the same
  value for now

42
Writing a web service

• Add \voorbeelden to your classpath and compile
  the code
• Now you can publish the Java class as a web
  service into Tomcat

43
Deploying a web service

• To deploy the Exchange service
• Launch tomcat again from the \voorbeelden
  directory
• Type the URL http//localhost8080/soap
• Click on Run the admin client

44
Deploying a webservice
45
What happens if you click on List?
46
Deploying a web service

• To deploy a web service (in this case the
  Exchange service) click on the deploy option and
  fill in the fields

47
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48
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49
Clarification

• ID web service identifier. In this case
  urndemo1exchange, with demo1 a namespace and
  exchange the service string
• Scope activation mode for the service.
• Request new instance of service is created with
  every individual request
• Session
• Application (see later)
• Methods methods to expose in the service (in
  this case getRate)

50
Clarification

• Provider type of web service. Apache SOAP only
  supports Java classes and Bean scripts
• Provider class/Static name of the Java class (in
  this case Exchange)

51
Deploying a web service

• After filling in the values, click the deploy
  button

52
Deploying a web service

• Click on the list button
• Click on the link

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54
Invoke a web service

• To invoke a web service from a Java client
• Import various packages (required by SOAP)
• Prepare your remote SOAP invocation by
  constructing a Call object and initialising its
  fields
• Encoding style Constants.NS_URI_SOAP_ENC

55
Invoke a web service

• Each parameter is represented by a Parameter
  object
• with the name of the argument,
• type of the argument,
• value of the argument and
• the encoding style for the argument (null selects
  the default)

56
Invoke a web service

• To invoke the method call, execute the invoke()
  method with the URL of the SOAP endpoint and the
  SOAPAction value
• If all goes well, the result is returned with
  primitives wrapped in their object equivalent

57
Invoke a web service

• import java.net.
• import java.util.
• import org.apache.soap. // Body, Envelope,
  Fault, Header
• import org.apache.soap.rpc. // Call, Parameter,
  Response
• public class Client
• public static void main( String args )
  throws Exception
• URL url new URL( "http//localhost8080/soa
  p/servlet/rpcrouter" )
• String urn "urndemo1exchange"
• Call call new Call() // prepare the
  service invocation
• call.setTargetObjectURI( urn )
• call.setMethodName( "getRate" )
• call.setEncodingStyleURI( Constants.NS_URI_SO
  AP_ENC )

58
Invoke a web service

• Vector params new Vector()
• params.addElement(new Parameter("country1",
  String.class, "USA", null))
• params.addElement(new Parameter("country2",
  String.class, Japan", null))
• call.setParams(params)
• try System.out.println("invoke
  service\n" " URL " url "\n URN "
  urn )
• //invoke the service
• Response response call.invoke( url, "" )
  if(!response.generatedFault()) // response
  was OK Parameter result response.getReturnVal
  ue() System.out.println("Result
  "result.getValue())

59
Invoke a web service

• else
• // an error occurred Fault f
  response.getFault() System.err.println("Fault
  "f.getFaultCode()", f.getFaultString())
• catch(SOAPException e) // call
  could not be sent properly System.err.println("SO
  APException " e.getFaultCode()",
  e.getMessage())

60
Invoke a web service

• Compiling and running this java program, gives
  the following result

61
Invoke a web service

• The web service output on Tomcat becomes

62
Invoke web services across the Internet

• Web services use a XML format over HTTP for
  messaging
• It is rather easy to invoke web service across
  the internet
• Visit XMethods (http//www.xmethods.net)
• This site hosts a selection of web services that
  are perfect for experimenting with this technology

63
Invoke web services across the Internet

• Click on the web service called Currency
  Exchange Rate
• This screen describes all the details of this web
  service, including the URN, the router endpoint
  and a description of each method available

64
Invoke web services across the Internet

• This Web service at XMethods provides the same
  methods as the one you just built
• To invoke the XMethods service
• Modify the URL to http//services.xmethods.net/soa
  p
• URN to urnmethods-CurrentExchange
• Run the client again

65
Running the Currency Exchange Rate Web Service
66
SOAP moves in mysterious ways or not?

• Q Where can I find SOAP in these examples?
• A you can see the SOAP messages exchanged
  between client and server via TCP tunneling GUI
• TCP tunneling GUI you can see TCP messages move
  between client and server

67
Sniffing SOAP

• With TCP tunneling GUI you can sniff SOAP
  messages by acting as a TCP router
• To see it in action
• Start Tomcat (starts up on port 8080 (default))
• Start (in a separate window) the TCP tunneler
  java org.apache.soap.util.net.TcpTunnelGui 8070
  localhost 8080This starts a TCP server on port
  8070 that acts as an intermediary between any
  client and port 8080 on the local host (serviced
  by Tomcat)

68
Sniffing SOAP
69
Sniffing SOAP

• Edit Client.java and change the web service URL
  to use port 8070 instead of 8080
• Compile and run it
• The result is

70
Sniffing SOAP
71
Sniffing SOAP

• On the left-hand outgoing SOAP request
• On the right-hand response
• This is almost self-describing

72
Anatomy of a SOAP request

• Protocol use to deliver soap messages is in this
  case HTTP
• But you can also use SMTP (see later, if mail
  server is not down -) )
• Headers differ from protocol to protocol, but the
  XML payload stays the same

73
SOAP/Http request

• POST /soap/servlet/rpcrouter HTTP/1.0 Host
  localhost8070 Content-Type text/xml
  Content-Length 461 SOAPAction ""
  ltSOAP-ENVEnvelope xmlnsSOAP-ENV"http//sche
  mas.xmlsoap.org/soap/envelope/
  xmlnsxsi"http//www.w3.org/1999/XMLSchema-instan
  ce xmlnsxsd"http//www.w3.org/1999/XMLSchema"
  gt ltSOAP-ENVBodygt ltns1getRate
  xmlnsns1"urndemo1exchange"
  SOAP-ENVencodingStyle"http//schemas.xmlsoap.org
  /soap/encoding/"gt ltcountry1
  xsitype"xsdstring"gtUSAlt/country1gt
  ltcountry2 xsitype"xsdstring"gtjapanlt/country2gt
  lt/ns1getRategt lt/SOAP-ENVBodygtlt/SOAP-ENVEn
  velopegt

74
SOAP request

• A SOAP request is sent as an HTTP POST with
  content type set to text/xml and field called
  SOAPAction set to either an empty string or the
  name of the SOAP method
• SOAPAction field allows a receiving web server to
  detect that its an incoming SOAP message and
  potentially route or filter it

75
SOAP request

• XML part of the SOAP request consists of 3
  portions
• Envelope defines the different namespaces
  (xmlnsSOAP-ENV, xmlnsxsi and xmlnsxsd)
• Header optional element. If a Header is present
  is must be the 1st child of the Envelope
• Body main payload of the message. When SOAP is
  used to perform RPC call, Body contains a single
  element that contains the method name, arguments
  and web service target address

76
SOAP request

• If a Header is present, Body must be its
  immediate sibling, otherwise it must be the first
  child of the Envelope

77
Anatomy of a SOAP response

• A SOAP/HTTP response is returned as an XML
  document within a standard HTTP reply whose
  content type is set to text/xml
• XML document is structured just like the request,
  except that Body contains the encoded method
  result

78
Anatomy of a SOAP response

• HTTP/1.0 200 OK Content-Type text/xml
  charsetUTF-8 Content-Length 425 Set-Cookie2
  JSESSIONID4x1b3dqoc1Version1DiscardPath"/soa
  p" Set-Cookie JSESSIONID4x1b3dqoc1Path/soap
  Servlet-Engine Tomcat Web Server/3.2.3 (JSP
  1.1 Servlet 2.2 Java 1.3.0 Windows 2000 5.0
  x86 java.vendorSun Microsystems Inc.)
• ltSOAP-ENVEnvelope xmlnsSOAP-ENV"http//schem
  as.xmlsoap.org/soap/envelope/
  xmlnsxsi"http//www.w3.org/1999/XMLSchema-instan
  ce xmlnsxsd"http//www.w3.org/1999/XMLSchema"
  gtltSOAP-ENVBodygtltns1getRateResponse
  xmlnsns1"urndemo1exchange"
  SOAP-ENVencodingStyle"http//schemas.xmlsoap.org
  /soap/encoding/"gt ltreturn xsitype"xsdfloat"gt144
  .52lt/returngtlt/ns1getRateResponsegtlt/SOAP-ENVBod
  ygtlt/SOAP-ENVEnvelopegt

79
SOAP Exceptions

• If an exception occurs at any time during the
  processing of a message, a SOAP exception is
  thrown
• SOAP exceptions are encoded similar to regular
  SOAP responses
• Body is used to contain info about the exception
• Illustration

80
SOAP Exceptions

• public class Exchange implements IExchange
• public float getRate( String country1, String
  country2 )
• throw new RuntimeException( "cannot calculate
  rate" )
• /
• System.out.println( "getRate( " country1
  ", " country2 " )" )
• return 144.52F // always return the same
  value for now
• /

81
SOAP Exceptions

• Shutdown and restart Tomcat (to use the new
  version of the web service)
• Invoke the Service using the Client program

82
SOAP Exceptions
83
SOAP Exceptions clarification

• http reply header indicates an exception by using
  status code 500
• XML payload contains an Envelope and Body (like a
  regular response) except that the content of the
  Body is a fault structure whose fields are
  defined as follows
• Faultcode SOAP-ENVClient, SOAP-ENVServer,
  SOAP-ENVVersionMismatch, SOAP-ENVMustUnderstand
• Faultstring description of the fault

84
SOAP Exceptions clarification

• Faultactor optional field that indicates the URI
  of the source of the fault
• Detail application-specific XML that contains
  detailed info about the fault

85
Exercise

• Adapt the example in such a way that you create a
  web service that is able to calculate the sum of
  two numbers
• Write also the corresponding client

86
Java SOAP
87
SOAP Implementations in Java

• Best known are
• Apache SOAP
• GLUE (http//www.themindelectric.com) can handle
  WSDL (download GLUE!)
• Implementators invented their own SOAP API
• Now standards for SOAP-based messaging RPC
  APIs
• JAXM
• JAX-RPC
• Standards implemented by Axis (next generation
  Apache SOAP implementation)

88
SOAP Data Encoding

• Data encoding encoding data in such a way that
  sender receiver understand its the meaning
• Serialisation of data (like in Java)
• Use of namespaces schemas
• Schemas not used for validation but as
  references to definitions of data elements

89
SOAP Data Encoding

• Namespace kind of dictionary that describes
  meaning
• Encoding style is defined in http//schemas.xmlsoa
  p.org/encoding
• Following namespaces are commonly found
• xmlnsSOAP-ENChttp//schemas.xmlsoap.org/encodin
  g
• xmlnsxsihttp//www.w3.org/2001/XMLSchema/instan
  ce/
• xmlnsxsdhttp//www.w3.org/2001/XMLSchema
• ltxyz xsitypexsdfloatgt3.14159lt/xyzgt

90
SOAP Data Encoding

• SOAP distinction between simple compound
  values
• simple simple piece of data (ex. strings,
  integers, floats,)

91
SOAP Data Encoding

• Compound value multiple pieces of data, with
  some relation to each other. Way to distinguish
  specific data value mechanism is referred as an
  accessor

92
SOAP Data Encoding
93
RPC

• Required for representing an RPC method call in
  SOAP
• Target object URI or resource address of the
  service
• Method name name of the method to be invoked
• Method parameters
• SOAP header data

94
RPC Service Activation

• Service activation or scope lifetime of an
  object
• In SOAP systems based on HTTP, 3 service
  activation models
• Request-level activation for each request, new
  instance of object is created, deleted when
  request is complete
• Application-level activation single instance of
  service object handles every method invocation
  for the entire lifetime of service application
• Session-level activation single instance of
  service object is used for all method invocations
  for the lifetime of the session

95
Simple service to illustrate different service
activation models

• Design service called CallCounterService
• Keeps track of number of method calls
• Code
• public class MethodCounter
• int _counter
• public MethodCounter()
• _counter 0
• public int getCount()
• return _counter
• public boolean doSomething()
• _counter 1 return true

96
Some remarks

• Methods are named according to JavaBeans naming
  convention!
• Our service class uses a no-argument constructor
• Java SOAP implementations load service classes
  dynamically Class.newInstance()
• Requires constructor with no arguments

97
Deploying the service in Apache SOAP

• Deployment no part of the SOAP specifications
• 2 different ways to deploy service in Apache
  SOAP
• Write manually a deployment descriptor
• Or using the SOAP Admin tool

98
Deployment descriptor

• ltisdservice xmlnsisdhttp//xml.apache.org/xml
  -soap/deployment idurnCallCounterServicegt
• ltisdprovider typejava scopeApplication
  methodsdoSomething getCountgt
• ltisdjava ClassMethodCounter
  staticfalse/gt
• lt/isdprovidergt
• ltisdfaultListenergt
• org.apache.soap.server.DOMFaultListener
• lt/isdfaultListenergt
• ltisdmappingsgtlt/isdmappingsgt
• lt/isdservicegt

99
Deployment descriptor

• Save this ex. CallCounterService.dd
• Deploy the service
• java org.apache.soap.server.ServiceManagerClient
  http//localhost8080/soap/sevlet/rpcrouter
  deploy CallCounterService.dd

100
Using the SOAP Admin tool

• Open browser with URL http//localhost8080/soap/
  
• Click Run the Admin Client
• Deploy service via the web interface

101
Next step writing a service client

• import java.net.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class GetCountApp
• public GetCountApp()
• public void callGetCountApp() throws Exception
• URL url new URL("http//localhost80
  80/soap/servlet/rpcrouter")
• Call call new Call()
• call.setTargetObjectURI("urnCallCounterService"
  )
• call.setMethodName("getCount")
• try
• Response resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object value ret.getValue()

102
Next step writing a service client

• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
  e.getFaultCode()")"e.getMessage())
• public static void main(String args) throws
  Exception
• GetCountApp GCA new GetCountApp()
• GCA.callGetCountApp()

103
Making it more spectacular

• import java.net.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class GetCountApp2
• public GetCountApp2()
• public void callGetCountApp() throws Exception
• URL url new URL("http//localhost8080/soap/s
  ervlet/rpcrouter")
• Call call new Call()
• call.setTargetObjectURI("urnCallCounterService"
  )

104
Making it more spectacular

• try
• call.setMethodName("doSomething")
• Response resp call.invoke(url,"")
• resp call.invoke(url,"")
• resp call.invoke(url,"")
• call.setMethodName("getCount")
• resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object value ret.getValue()
• System.out.println("Result is " value)
• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
  e.getFaultCode()")"e.getMessage())

105
Making it more spectacular

• public static void main(String args) throws
  Exception
• GetCountApp2 GCA new GetCountApp2()
• GCA.callGetCountApp()

106
Changing the service activation

• .. to requestlevel
• New instance is created for each method
  invocation object is destroyed when invocation
  is complete
• Change Scope in Admin tool to request!
• Run the examples again!

107
Changing the service activation

• session-level scope
• Run the examples again!
• Common use for this? Online shopping

108
Passing parameters

• Using Apache SOAP

109
Passing parameters

• Create a StockPrice class that allows passing of
  parameters
• public class StockPrice
• public float getPrice(String stock, String
  currency)
• float result
• result (float)75.33
• System.out.println("Price is "result)
• return result

110
Passing parameters

• Deploy this service with scope application
• Client program (in Apache SOAP) to access the
  service

111
Passing parameters (Apache SOAP)

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class StockPriceApp
• public StockPriceApp()
• public void callStockPrice() throws Exception
• try
• URL url new
  URL("http//localhost8080/soap/servlet/rpcrouter"
  )
• Call call new Call()
• call.setTargetObjectURI("urnStockPriceServic
  e")
• call.setEncodingStyleURI(Constants.NS_URI_SOA
  P_ENC)

112
Passing parameters (Apache SOAP)

• String stock KAHOSL"
• String currency "Euro"
• Vector params new Vector()
• params.addElement(new Parameter("stock",
  String.class, stock, null))
• params.addElement(new Parameter("currency",
  String.class, currency, null))
• call.setParams(params)
• call.setMethodName("getPrice")
• Response resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object value ret.getValue()
  System.out.println("Price is " value)

113
Passing parameters (Apache SOAP)

• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
• e.getFaultCode() ")" e.getMessage())
• public static void main(String args) throws
  Exception
• StockPriceApp SPA new StockPriceApp()
• SPA.callStockPrice()

114
Passing parameters

• For setting up parameters, call the
  setEncodingStyleURI of the Call object
• Each parameter is held in instance of
  org.apache.soap.rpc.Parameter
• Constructor of this class takes
• Parameters name
• Class of the object that contains parameter value
• Object that contains the parameter value
• Encoding style URI for the parameter

115
Complex data types passing arrays as parameters

• Write a service that return information about a
  collection of stock symbols
• For the moment service that returns the total
  number of shares
• Service is called urnBasicTradingService and
  associated method is getTotalVolume

116
Passing arrays as parameters service

• public class BasicTradingService
• public BasicTradingService()
• public int getTotalVolume(String stocks)
• //get the volumes for each stock from some
• //data feed and return the total
• int total 123456
• return total

• Deploy this service (scope application)

117
Passing arrays as parameters client

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class VolumeClient
• public VolumeClient()
• public void callVolumeClient() throws Exception
• URL url new URL("http//localhost8080/soap
  /servlet/rpcrouter")
• Call call new Call()
• call.setTargetObjectURI("urnBasicTradingService
  ")
• call.setEncodingStyleURI(Constants.NS_URI_SOAP_E
  NC)
• String stocks "KAHO", "VAKIT", "SUN"
• Vector params new Vector()
• params.addElement(new Parameter("stocks",
  String.class, stocks, null))
• call.setParams(params)

118
Passing arrays as parameters client

• try
• call.setMethodName("getTotalVolume")
• Response resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object value ret.getValue()
• System.out.println("Total Volume is "
  value)
• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
• e.getFaultCode() ")" e.getMessage())
• public static void main(String args) throws
  Exception
• VolumeClient VC new VolumeClient()
• VC.callVolumeClient()

119
Heterogeneous arrays

• Adapt the service
• public class BasicTradingService2
• public BasicTradingService2()
• public int getTotalVolume(String stocks)
• //get the volumes for each stock from some
• //data feed and return the total
• int total 123456
• return total

120
Heterogeneous arrays

• public String executeTrade(Object params)
• String result
• try String stock (String)params0
• Integer numShares (Integer)params1
• Boolean buy (Boolean)params2
• String orderType "Buy"
• if (false buy.booleanValue())
• orderType "Sell"
• result (orderType " " numShares " of "
  stock)
• catch(ClassCastException e)
• result "Bad Parameter Type Encountered"
• return result

121
Corresponding Client

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class TradingClient
• public TradingClient()
• public void callTradingClient() throws
  Exception
• URL url new URL("http//localhost8080/soap/s
  ervlet/rpcrouter")
• Call call new Call()
• call.setTargetObjectURI("urnBasicTradingService
  2")
• call.setEncodingStyleURI(Constants.NS_URI_SOAP_E
  NC)
• Object multiParams "MS", new Integer(200),
  new Boolean(true)
• Vector params new Vector()

122
Corresponding Client

• params.addElement(new Parameter("params",
  Object.class, multiParams, null))
• call.setParams(params)
• try
• call.setMethodName("executeTrade")
• Response resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object value ret.getValue()
• System.out.println("Trade description "
  value)
• catch(SOAPException e)
• System.err.println("Caught SOAPException
  (" e.getFaultCode() ")" e.getMessage())

123
Corresponding Client

• public static void main(String args) throws
  Exception
• TradingClient TC new TradingClient()
• TC.callTradingClient()

124
Returning arrays

• Add method to our service, that returns String
  that contains the symbols for the most actively
  traded stocks
• public String getMostActive()
• //get the most actively traded stocks of the
  day
• String actives "QD", "FB", "LD", "TM"
• return actives

125
Client application

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• public class MostActiveClient
• public MostActiveClient()
• public void callMostActiveClient() throws
  Exception
• URL url new URL("http//localhost8080/soap
  /servlet/rpcrouter")
• Call call new Call()
• call.setTargetObjectURI("urnBasicTradingService
  3")
• call.setMethodName("getMostActive")
• Response resp

126
Client application

• try
• resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• String value (String)ret.getValue()
• int cnt value.length
• for (int i 0 iltcnt i)
• System.out.println(valuei)
• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
• e.getFaultCode() ") e.getMessage())

127
Client application

• public static void main(String args) throws
  Exception
• MostActiveClient MAC new MostActiveClient()
• MAC.callMostActiveClient()

128
Passing custom types as parameters

• Suppose a Java class that contains all data
  necessary to specify a stock trade
• Common way to express properties of Java class is
  using JavaBeans design pattern
• Pattern specify naming convention for the classs
  access methods

129
Passing custom types as parameters JavaBeans
pattern

• public void setltPropertyNamegt(ltPropertyTypegt
  value)
• public ltPropertyTypegt getltPropertyNamegt()
• If ltPropertyTypegt is boolean, get Method can be
  replaced by
• public boolean isltPropertyNamegt()
• Following this naming convention for accessors,
  the accessor methods can be determined at runtime
  (using Javas reflection mechanism)
• Convenient way for SOAP implementations to access
  data values of a Java class instance in order to
  serialize the data in a SOAP message

130
Passing custom types as parameters data?

• Define stock in terms of data it has to contain
• Stock symbol (String)
• Buy or sell? (boolean)
• Number of shares (integer)
• ltelement nameStockTrade typeStockTrade/gt
• ltcomplexType nameStockTradegt
• ltelement namesymbol typexsdstring/gt
  ltelement namebuy typexsdboolean/gt
• ltelement namenumshares typexsdint/gt
• lt/complexTypegt

131
Create a custom Java class StockTrade_ClientSide

• public class StockTrade_ClientSide
• String _symbol
• boolean _buy
• int _numShares
• public StockTrade_ClientSide()
• public StockTrade_ClientSide(String symbol,
  boolean buy, int numShares)
• _symbol symbol
• _buy buy
• _numShares numShares
• public String getSymbol()
• return _symbol
• public void setSymbol(String symbol)
• _symbol symbol

132
StockTrade_ClientSide

• public boolean isBuy()
• return _buy
• public void setBuy(boolean buy)
• _buy buy
• public int getNumShares()
• return _numShares
• public void setNumShares(int numShares)
• _numShares numShares

133
Create a custom Java class StockTrade_ServerSide

• public class StockTrade_ServerSide
• int _shares
• boolean _buyOrder
• String _stock
• public StockTrade_ServerSide()
• public String getSymbol()
• return _stock
• public void setSymbol(String stock)
• _stock stock

134
StockTrade_ServerSide

• public boolean isBuy()
• return _buyOrder
• public void setBuy(boolean buyOrder)
• _buyOrder buyOrder
• public int getNumShares()
• return _shares
• public void setNumShares(int shares)
• _shares shares

135
Passing custom types as parameters adapting the
service

• Add new method to urnBasicTradingService
  service, called executeStockTrade()
• public String executeStockTrade(StockTrade_Server
  Side trade)
• Object params new Object3
• params0 trade.getSymbol()
• params1 new Integer(trade.getNumShares())
• params2 new Boolean(trade.isBuy())
• return executeTrade(params)

136
Deploying the service

• Add
• encodingStyle http//schemas.xmlsoap.org/soap/en
  coding/,
• elementType urnBasicTradingService4StockTrade,
  
• javaTypeStockTrade_ServerSide,
• java2XMLClassName org.apache.soap.encoding.soape
  nc.BeanSerializer,
• xml2JavaClassName org.apache.soap.encoding.soape
  nc.BeanSerializer

137
Write new Client

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• import org.apache.soap.encoding.
• import org.apache.soap.encoding.soapenc.
• import org.apache.soap.util.xml.
• public class StockTradeClient
• public StockTradeClient()
• public void callStockTradeClient() throws
  Exception
• URL url new URL("http//localhost8080/soap
  /servlet/rpcrouter")
• Call call new Call()
• SOAPMappingRegistry smr new
  SOAPMappingRegistry()
• call.setSOAPMappingRegistry(smr)
• call.setEncodingStyleURI(Constants.NS_URI_SOAP_E
  NC)
• call.setTargetObjectURI("urnBasicTradingService
  4")

138
Write new Client

• call.setMethodName("executeStockTrade")
• BeanSerializer beanSer new BeanSerializer()
• //Map the Stock Trade type
• smr.mapTypes(Constants.NS_URI_SOAP_ENC,
• new QName("urnBasicTradingService4","StockT
  rade"),
• StockTrade_ClientSide.class, beanSer,
  beanSer)
• //create an instance of the stock trade
• StockTrade_ClientSide trade new
  StockTrade_ClientSide("QSD", false, 400) Vector
  params new Vector()
• params.addElement(new Parameter("trade",
  StockTrade_ClientSide.class, trade, null))
• call.setParams(params)
• Response resp
• try resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• Object desc ret.getValue()
• System.out.println("Trade description "
  desc)

139
Write new Client

• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
• e.getFaultCode() ")"e.getMessage())
• public static void main(String args) throws
  Exception
• StockTradeClient STC new StockTradeClient()
• STC.callStockTradeClient()

140
Returning custom types

• Enhance trading service by offering a method that
  takes a single stock symbol as parameter and
  returns its high and low prices for a day
• Create 2 new classes
• HighLow_ServerSide
• HighLow_ClientSide

141
HighLow_ServerSide

• public class HighLow_ServerSide
• public float _high
• public float _low
• public HighLow_ServerSide()
• public HighLow_ServerSide(float high, float
  low)
• setHigh(high)
• setLow(low)
• public float getHigh()
• return _high

142
HighLow_ServerSide

• public void setHigh(float high)
• _high high
• public float getLow()
• return _low
• public void setLow(float low)
• _low low

143
HighLow_ClientSide

• public class HighLow_ClientSide
• public float _high
• public float _low
• public String toString()
• return "High " _high " Low " _low
• public HighLow_ClientSide()
• public float getHigh()
• return _high
• public void setHigh(float high)
• _high high

144
HighLow_ClientSide

• public float getLow()
• return _low
• public void setLow(float low)
• _low low

145
Returning custom types adapting service

• Add new method
• public HighLow_ServerSide getHighLow(String
  stock)
• //retrieve the high and low for the specified
  stock
• return new HighLow_ServerSide((float)110.375,(flo
  at)109.5)

146
Deploy the service

• Add 2 mappings
• Mapping 1
• encodingStyle http//schemas.xmlsoap.org/soap/en
  coding/,
• elementType urnBasicTradingService5StockTrade,
  
• javaType StockTrade_ServerSide,
• java2XMLClassName org.apache.soap.encoding.soape
  nc.BeanSerializer,
• xml2JavaClassName org.apache.soap.encoding.soape
  nc.BeanSerializer
• Mapping 2
• encodingStyle http//schemas.xmlsoap.org/soap/en
  coding/,
• elementType urnBasicTradingService5HighLow,
• javaType HighLow_ServerSide,
• java2XMLClassName org.apache.soap.encoding.soape
  nc.BeanSerializer,
• xml2JavaClassName org.apache.soap.encoding.soape
  nc.BeanSerializer

147
Write new client

• import java.net.
• import java.util.
• import org.apache.soap.
• import org.apache.soap.rpc.
• import org.apache.soap.encoding.
• import org.apache.soap.encoding.soapenc.
• import org.apache.soap.util.xml.
• public class HighLowClient
• public HighLowClient()
• public void callHighLowClient() throws
  Exception
• URL url new URL("http//localhost8080/soap/s
  ervlet/rpcrouter")
• Call call new Call()
• SOAPMappingRegistry smr new
  SOAPMappingRegistry()

148
Write new client

• call.setSOAPMappingRegistry(smr)
• call.setEncodingStyleURI(Constants.NS_URI_SOAP_E
  NC)
• call.setTargetObjectURI("urnBasicTradingService
  5")
• call.setMethodName("getHighLow")
• BeanSerializer beanSer new BeanSerializer()
• //Map the High/Low type
• smr.mapTypes(Constants.NS_URI_SOAP_ENC,
• new QName("urnBasicTradingService5","HighLow"),
  
• HighLow_ClientSide.class, beanSer, beanSer)
• String stock "XYZ"
• Vector params new Vector()
• params.addElement(new Parameter("stock",
  String.class, stock, null))
• call.setParams(params)
• Response resp

149
Write new client

• try
• resp call.invoke(url,"")
• Parameter ret resp.getReturnValue()
• HighLow_ClientSide hilo (HighLow_Client
  Side)ret.getValue()
• System.out.println(hilo)
• catch(SOAPException e)
• System.err.println("Caught SOAPException ("
• e.getFaultCode() ")"e.getMessage())
• public static void main(String args) throws
  Exception
• HighLowClient STC new HighLowClient()
• STC.callHighLowClient()

150
SOAP over SMTP

• http//ws.apache.org/soap/faq/faq_chawke_smtp.html
  

151
How about SOAP SMTP?

• Before starting make sure that SOAP over HTTP
  works
• SOAP is transport independent protocol
• Apache SOAP includes classes which permit SOAP
  messages using email
• A class named SMTP2HTTPBridge must be running on
  the server
• Kind of bridge mapping requests between HTTP and
  SMTP
• It converts e-mail SOAP messages to and from HTTP
  SOAP messages

152
Running the Apache SOAP SMTP Bridge on the Server

• Include pop3.jar and smtp.jar in your classpath
• Use a test email account (ex. mail1)
• Execute the following command
• java org.apache.soap.server.SMTP2HTTPBridge 2500
  pop.kahosl.be mail1 mail1x http//localhost8080/s
  oap/servlet/rpcrouter smtp.kahosl.be

153
Running the Apache SOAP SMTP Bridge on the Server

• Where
• 2500 is the poll delay
• pop.kahosl.be is the pop3 server
• mail1 is the login on the pop3 server
• mail1x is the password
• http//localhost8080/soap/servlet/rpcrouter
• smtp.kahosl.be is the SMTP server

154
Running the Apache SOAP SMTP Bridge on the Server

• The result should be
• See demo

155
Running an Apache Client using SMTP

• Find an existing SOAP client making invocations
  over HTTP
• Modify the code to use SMTP instead of HTTP

156
Running an Apache Client using SMTP

• URL url new URL( "mailtomail1_at_kahosl.be" )
• String urn "urndemo1exchange"
• String smtpserver "smtp.kahosl.be"
• String popserver "pop.kahosl.be"
• String poplogin "mail1"
• String poppasswd "mail1x"
• String replyaddr poplogin"_at_kahosl.be"
• SOAPTransport ss new SOAPSMTPConnection (
• replyaddr, "SOAP Request", smtpserver,
  3500, popserver, poplogin, poppasswd)
• Call call new Call()
• call.setSOAPTransport(ss)

157
SOAP and SSL

• http//ws.apache.org/soap/docs/install/FAQ_Tomcat_
  SOAP_SSL.html
• Note this website is rather obsolete

158
How can we make SOAP secure?

• Copy (hint look in Glue lib directory)
• jsse.jar
• jcert.jar
• jnet.jar
• to lib directory of Tomcat
• Generate client and server certificates
• Generate a server key and certificate
• keytool -genkey -alias tomcat-sv -dname
  "CNnewton.kahosl.be, OUVakgroepIT, OKaHo
  Sint-Lieven, LGent, SOost-Vlaanderen, CBE"
  -keyalg RSA -keypass changeit -storepass changeit
  -keystore server.keystore

159
How can we make SOAP secure?

• Export Server Certificate
• keytool export alias tomcat-sv storepass
  changeit file server.cer keystore
  server.keystore
• Generate client key and certificate
• keytool -genkey -alias tomcat-cl -dname
  "CNClient, OUVakgroepIT, OKaHo Sint-Lieven,
  LGent, SOost-Vlaanderen, CBE" -keyalg RSA
  -keypass changeit -storepass changeit -keystore
  client.keystore

160
How can we make SOAP secure?

• Export Client Certificate
• keytool export alias tomcat-cl storepass
  changeit file client.cer keystore
  client.keystore
• Import the certificates into Keystores
• Add client certificate to servers keystore
  servers certificate added to clients keystore
• keytool import v trustcacerts alias tomcat
  file server.cer keystore client.keystore
  keypass changeit storepass changeit
• keytool import v trustcacerts alias tomcat
  file client.cer keystore server.keystore
  keypass changeit storepass changeit

161
How can we make SOAP secure?

• Adapt server.xml in conf subdirectory of Tomcat
• Uncomment the part about SSL and add
• ltFactory className"org.apache.coyote.tomcat4.Co
  yoteServerSocketFactory" clientAuth"false"
  keystoreFile"c\javaxml2\voorbeelden\ssl\server.
  keystore" protocol"TLS"/gt

162
How can we make SOAP secure?

• Test your https server
• https//localhost8443
• Modify your SOAP client! Add
• import javax.net.ssl.SSLSocketFactory
• import java.security.Security
• System.setProperty("javax.net.ssl.trustStore",
  "c\\javaxml2\\voorbeelden\\ssl\\client.keystore")
  
• System.setProperty("javax.protocol.handler.pkgs",
  "com.sun.net.ssl.internal.www.protocol")
• Security.addProvider(new com.sun.net.ssl.internal.
  ssl.Provider())
• URL url new URL( "https//localhost8443/soap/se
  rvlet/rpcrouter" )