Departamento de Engenharia Informática. Systems Integration. Web Services and BPEL Tutorial

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1 Departamento de Engenharia Informática Systems Integration Web Services and BPEL Tutorial IE 2016 In this tutorial, we shall create a Web service in Java that validates a credit card number. In addition, we shall create a BPEL process that implements a process for validating credit cards. 1. Open JDeveloper and use the Default Role. 2. Create an application and project by following these steps: In the menu, select File -> New... In the Categories pane, select General. Click on Generic Application and on the OK button. In the Create Generic Application window, change the Application Name to WebServiceExample and click on Next. IST/DEI Pág. 1 de 17

2 In Step 2 of the Create Generic Application window, change the Project Name to CreditCardWS. Click on Finish. Creating a Web service with Java 3. In the Application Navigator, right-click on the project name (CreditCardWS) and select New. 4. In the New Gallery window, select General -> Java in the Categories pane. Then, select Java Class in the Items pane. Click on OK. IST/DEI Pág. 2 de 17

3 5. In the Create Java Class window, change the Name of the class to CreditCardService. Click on OK. 6. Add the following method to the CreditCardService class; this method implements an algorithm for validating credit card numbers (also known as the Luhn algorithm): public boolean validatenumber(string number) { // number must be validated as 0..9 numeric first!! int digits = number.length(); int oddoreven = digits & 1; long sum = 0; for (int count = 0; count < digits; count++) { int digit = 0; try { digit = Integer.parseInt(number.charAt(count) + ""); } catch(numberformatexception e) { return false; } // The bitwise & operator performs a bitwise AND operation. // The bitwise ^ operator performs a bitwise exclusive OR operation. // The bitwise operator performs a bitwise inclusive OR operation. } if (((count & 1) ^ oddoreven) == 0) { // not digit *= 2; if (digit > 9) { digit -= 9; } } sum += digit; } return (sum == 0)? false : (sum % 10 == 0); IST/DEI Pág. 3 de 17

4 7. Click on Save All to save your work. 8. Any Java method can be published as Web service. In order to create a Web service in JDeveloper from a Java class, right-click on CreditCardService.java and select Create Web Service. This will start a wizard for creating the Web service. 9. In the Create Java Web Service Step 2 of 11 window, select Java EE 1.5, with support for JAX-WS Annotations as the deployment platform. Click on Next. 10. In the Create Java Web Service Step 3 of 11 window, you could change the Web service name and port name. We will use the default values, thus click on Next. IST/DEI Pág. 4 de 17

5 11. In the Create Java Web Service Step 4 of 11 window, check the option SOAP 1.2 Binding as the message format. Click on Next. 12. In the Create Java Web Service Step 5 of 11, the window presents all the possible methods in the Class that can be published. Since we created only one method in this class, it should be selected by default. The remaining pages are for including any additional classes the service may need, configuring policies for the service, and providing the handler details. Since we are not going to change any of the default values, just click on Finish. The class is updated with the annotation needed for publishing a Web service to an application server. IST/DEI Pág. 5 de 17

6 Deploying a Web service to the Oracle WebLogic Server 13. In order to deploy the Web service to the application server, right-click on the project name (CreditCardWS) in the Application Navigator and select Deploy -> Web Services. This will start a wizard. 14. In the Deploy WebServices window, select the action Deploy to Application Server. Click on Next. 15. Select the application server connection that we have created in the previous tutorial (VM_SOA_AppSrv). IST/DEI Pág. 6 de 17

7 16. In order to deploy the Web service to a server instance, select Deploy to selected instances in the domain and AdminServer. Click on Next. 17. Click on Finish. Testing the Web service with JDeveloper 11g 18. In the menu, select Tools -> HTTP Analyzer. 19. Click on the Create New Request. IST/DEI Pág. 7 de 17

8 20. Click on the Open WSDL and specify the URL of the WSDL. For example: 21. Test the Web service. IST/DEI Pág. 8 de 17

9 Creating a credit card validation process in BPEL 22. We will now create a new application and project; hence, close the Web service application if it is still open. 23. Now create an application and project by following these steps: In the menu, select File -> New... In the Categories pane, select General. Click on Generic Application and on the OK button. In the Create Generic Application window, change the Application Name to WebServiceBPELExample and click on Next. In Step 2 of the Create Generic Application window, change the Project Name to CreditCardValidatorPrj. Within the Project Technologies tab, click on SOA and on the right arrow button (i.e, > ). i. SOA should appear in the Selected pane as shown below. Click on Next. In Step 3, change the Composite Name to CreditCardValidator and select Empty Composite in the Composite Template pane. Click on Finish IST/DEI Pág. 9 de 17

10 Creating a SOA Composite Application with a BPEL Process for Validating Credit Cards 24. Select composite.xml in the Design view. This is the SOA Composite Editor which currently contains no service components. 25. Drag-and-drop the BPEL process to the Components lane. 26. The Create BPEL Process should open automatically. Change the following information: Select BPEL 2.0 Specification Name: CreditCardProcess Template: Synchronous BPEL Process The checkbox Expose as a SOAP service should be selected The composite application diagram should look like this: IST/DEI Pág. 10 de 17

11 27. Next, we have to add a partner service to the composite application, which is the Web service that we created for validating credit card numbers. Hence, drag-and-drop a Web Service binding component to the External References lane of the composite diagram. 28. The Create Web Service window opens. First, you should change the Name; for example, the external service could be called CreditCardNumberValidator. 29. Enter the WSDL URL and Port type of the Web service that we deployed in the previous section. Click on OK. IST/DEI Pág. 11 de 17

12 30. We now have to wire the external references to the BPEL process. Hence, drag a wire from the BPEL process service component (CreditCardProcess) to the external reference (CreditCardNumberValidator). The composite application diagram should look like this: 31. Open the CreditCardProcess.bpel in the Application Navigator (you can also open the CreditCardProcess.bpel by double-clicking the BPEL service component on the composite application diagram). 32. Add an Assign activity between the receiveinput and replyoutput. 33. Add an Invoke activity below the Assign activity. 34. Add an If activity below the Invoke activity. 35. In the If branch, add an Assign activity. 36. In the Else branch, add an Assign activity. Your diagram should look like this: IST/DEI Pág. 12 de 17

13 37. Note that a partner link has already been generated, because we wired the BPEL process to an external reference (the Web service for validating Credit Card numbers) on the composite diagram. We will now use the invoke activity to invoke this service by visually connecting it to the partner link. This will open Edit Invoke window. 38. In the Edit Invoke window, change the Name to InvokeCreditCardValidator. IST/DEI Pág. 13 de 17

14 39. In the Edit Invoke window, click on the Input tab (within the General tab) and create a variable for the input message of the web service by clicking on the + icon. 40. A Create Variable window should open. Use the default values and click on OK. 41. In the Edit Invoke window, click on the Output tab (within the General tab) and create a variable for the output message of the web service by clicking on the + icon. 42. A Create Variable window should open. Use the default values and click on OK. 43. Double-click Assign1 activity, visually connect the inputvariable to the InvokeCreditCardValidator_validateNumber_InputVariable (N.B., you should fully expand the variables and connect the leaf nodes) in order to copy the content of the input message of the BPEL process to the input message of the Web service that will be invoked. 44. Change the name of the Assign1 activity to AssignWSInput. 45. Double-click the If activity, change the Name to iscreditcardvalid and the following Condition (you may also use the XPath Expression Builder): IST/DEI Pág. 14 de 17

15 The condition above uses the content of the output message of the Web service to decide the branch that it should follow; in other words, the process will follow the left branch if the credit card number is valid and the right branch otherwise. 46. We will now set the output message of the BPEL process in the left branch; hence, double-click the Assign2 activity. Change the Name to AssignOutputTrue. Next, use the concat() function as below to create the content of the output message. Finally, drag the expression in order to assign it to the client:result of the outputvariable. IST/DEI Pág. 15 de 17

16 47. Similarly, set the output message of the BPEL process in the right branch; hence, double-click the Assign3 activity. Change the Name to AssignOutputFalse. Next, use the concat() function as below to create the content of the output message. Finally, drag the expression in order to assign it to the client:result of the outputvariable. IST/DEI Pág. 16 de 17

17 48. Save the application. 49. Deploy the application to the server. 50. Test the application with the Enterprise Manager 11g. IST/DEI Pág. 17 de 17