<\/p>\n
In this article I want to show you how to build a SOAP JAX-WS<\/strong> (Java API for XML Web Services) client using the Liferay infrastructure. Let's start with a concrete example. The entire development project for this article is available on my GitHub liferay-72-soap-client-examples repository<\/strong><\/a>.<\/div>\n1. Overview<\/h2>\n
<\/p>\n
1. Overview<\/h2>\nLet's consider the SOAP Calculator service whose WSDL<\/a> (Web Services Description Language) descriptor is available at the following address http:\/\/www.dneonline.com\/calculator.asmx<\/a> which exposes the four arithmetic operations between two integers.<\/div>\n <\/p>\n
\nThe goal is to make this service available to any application installed on our Liferay instance. We then structure our Liferay project in this way:<\/div>\n <\/p>\n
\n- \nImplementation of the calculator-api<\/strong> module. This module defines the APIs that each application can invoke to use the services of arithmetic operations (addition, subtraction, division and multiplication);<\/div>\n<\/li>\n
- \nImplementation of the calculator-service<\/strong> module. This module implements the APIs defined by the calculator-api module and acts as a client to the SOAP Calculator service;<\/div>\n<\/li>\n
- \nImplementation of the calculator-gogo-shell <\/strong>module. This module implements the Gogo Shell commands that use the APIs defined by the calculator-api module to perform the arithmetic operations;<\/div>\n<\/li>\n
- \nImplementation of the calculator-web<\/strong> module. This module implements a standard MVC portlet that uses the APIs defined by the calculator-api module to perform the arithmetic operations.<\/div>\n<\/li>\n<\/ol>\n
<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/ModuleRelationshipDiagram.png\" "\\"Figure")
<\/a>Figure 1 - Diagram of the relationships between the modules<\/p><\/div>\n<\/div>\n
<\/div>\nThe figure below shows the class diagram of the main classes of the various modules. In detail:<\/div>\n <\/p>\n
\n- \ncalculator-api<\/strong><\/div>\n
\n- \n<\/b>Calculator<\/em> is the interface that defines the arithmetic operations between two integers;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \ncalculator-service<\/strong><\/div>\n
\n- \nCalculatorClientImpl<\/em> implements the APIs defined by the Calculator interface and acts as a client to the SOAP Calculator service;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \ncalculator-web<\/strong><\/div>\n
\n- \nAddOperationMVCActionCommand<\/em>:\u00a0MVC Action Command of the Calculator Web Module for the request of the addition operation;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \ncalculator-gogo-shell<\/strong><\/div>\n
\n- \nCalculatorCommand<\/em>: Gogo Shell Commands of the Calculator Gogo Shell Module.<\/div>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/ClassDiagram_2-1024x366.png\")
<\/a>Figure 2 - Class diagram<\/p><\/div>\n
<\/p>\n
1 -\u00a0Implementation of the SOAP client<\/h2>\nIn order to call the SOAP service we need to create the stubs that will be our interface that will allow us to interact with the remote service through the SOAP protocol.<\/div>\n <\/p>\n
To create all the java code we need, starting from the WSDL document, we usually use the wsimport<\/strong><\/a> tool.\u00a0Instead of using the command-line tool directly, we'll set up the project to use a Gradle task that does everything for us.<\/div>\n<\/div>\n <\/p>\n
The one shown below is the build.gradle file of the calculator-service module. The parts highlighted make it possible to use the Gradle gradle-jaxws-plugin<\/b> plugin.<\/div>\n <\/p>\n
The second block highlighted, sets the directory of WSDL documents<\/em> and the directory that will contain the java files generated from the WSDL document.\u00a0The WSDL document can be downloaded from the address http:\/\/www.dneonline.com\/calculator.asmx?WSDL<\/a> and saved in the directory indicated.<\/div>\n<\/div>\n\nbuildscript {\r\n repositories {\r\n maven {\r\n url \"https:\/\/plugins.gradle.org\/m2\/\"\r\n }\r\n }\r\n dependencies {\r\n classpath \"gradle.plugin.cz.swsamuraj:gradle-jaxws-plugin:0.6.1\"\r\n }\r\n}\r\n\r\napply plugin: \"cz.swsamuraj.jaxws\"\r\n\r\n\r\ndependencies {\r\n compileOnly group: \"com.liferay.portal\", name: \"com.liferay.portal.kernel\", version: \"4.4.0\"\r\n compileOnly group: \"org.osgi\", name: \"org.osgi.service.component.annotations\", version: \"1.3.0\"\r\n compileOnly project(\":modules:calculator:calculator-api\")\r\n}\r\n\r\n\r\njaxws {\r\n wsdlDir = 'src\/main\/resources\/META-INF\/wsdl'\r\n generatedSources = 'generatedsources\/src\/main\/java'\r\n}<\/pre>\n<\/div>\nAfter editing the build.gradle file you should (and after a refresh gradle project) the new Gradle tasks and in particular: wsImport<\/strong><\/div>\n<\/div>\n<\/div>\n\n![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/WebServiceGradleTask.png\" "\\"Figure")
<\/a>Figure 3 - New Gradle tasks added after configuring the gradle-jaxws-plugin plugin<\/p><\/div>\n<\/div>\n
<\/div>\nAt this point all that remains is to run the wsImport<\/em> task whose output will be the generation of the Java classes (stub). Now we have everything we need to be able to implement the SOAP client.<\/div>\n<\/div>\n\n![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/GenerateStubJavaClass.png\" "\\"Figure")
<\/a>Figure 4 - Java classes generated by the Gradle wsImport task starting from the WSDL of the SOAP Calculator service.<\/p><\/div>\n
<\/div>\nThe code shown below is the implementation of the CalculatorClientImpl<\/strong> class that implements the Calculator interface and uses the stub classes to get the interface to SOAP services.<\/div>\n <\/p>\n
The _getService()<\/strong> method gets the reference to the CalculatorSOAP<\/strong> interface, the latter is used within all the methods that implement arithmetic operations.<\/div>\n <\/p>\n
Note that CalculatorClientImpl is a DS component<\/strong><\/a>, this will allow us to use the services of the Calculator interface with the simple @Reference<\/strong> annotation.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.webservice.calculator.client.soap;\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(immediate = true, property = {}, service = Calculator.class)\r\npublic class CalculatorClientImpl implements Calculator {\r\n\r\n\r\n @Override\r\n public int add(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().add(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int divide(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().divide(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int multiply(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().multiply(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int subtract(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().subtract(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n private CalculatorSoap _getService() throws CalculatorServiceException {\r\n if (Validator.isNull(_calculatorSoap)) {\r\n try {\r\n org.tempuri.Calculator calculator =\r\n new org.tempuri.Calculator();\r\n _calculatorSoap = calculator.getCalculatorSoap();\r\n }\r\n catch (WebServiceException wse) {\r\n throw new CalculatorServiceException(wse.getMessage(), wse);\r\n }\r\n return _calculatorSoap;\r\n }\r\n else {\r\n return _calculatorSoap;\r\n }\r\n }\r\n\r\n private CalculatorSoap _calculatorSoap;\r\n}<\/pre>\nFrom this moment we can use the Calculator service on any module. Who uses the service is absolutely abstract from the fact that the implementation uses external SOAP services.<\/p>\n
2 -\u00a0Implementation of Gogo Shell commands<\/h2>\nNow let's see how to use the service to create a series of Gogo Shell commands that allow us to perform arithmetic operations.<\/div>\n <\/p>\n
The following code shows the class CalculatorCommand which uses the Calculator service referenced by the @Reference annotation and implement the arithmetic operations we defined in the Calculator interface.<\/div>\n <\/p>\n
I have reported only the most significant parts of the code that are highlighted.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.webservice.calculator.gogoshell;\r\n\r\nimport it.dontesta.labs.liferay.webservice.calculator.api.Calculator;\r\n\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(\r\n property = {\r\n \"osgi.command.function=add\",\r\n \"osgi.command.function=divide\",\r\n \"osgi.command.function=multiply\",\r\n \"osgi.command.function=subtract\",\r\n \"osgi.command.scope=calculator\"\r\n },\r\n service = Object.class\r\n)\r\npublic class CalculatorCommand implements Calculator {\r\n public int add(int number1, int number2)\r\n throws CalculatorOperationException {\r\n return getCalculatorService().add(number1, number2);\r\n }\r\n\r\n ...\r\n\r\n @Reference(policyOption = ReferencePolicyOption.GREEDY)\r\n private volatile Calculator _calculator;\r\n}<\/pre>\nOnce the module has been deployed, we have the commands to make the arithmetic operations available. Just connect to the Gogo Shell and try.<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/GogoShellCalculatorCommands_1-1024x84.png\")
<\/a>Figure 5 - Division by zero!<\/p><\/div>\n
<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/GogoShellCalculatorCommands_2-1024x62.png\")
<\/a>Figure 6 - Error in case of connectivity problems<\/p><\/div>\n
<\/h2>\n3 -\u00a0Implementation of Calculator Web<\/h2>\nWe have seen how to use the Calculator service for Gogo Shell commands, why not implement a simple very basic web calculator?<\/div>\n <\/p>\n
In the class diagram of figure 2 we have seen that there are four MVC Command, one for each operation.<\/div>\n <\/p>\n
Following is the MVC Command code responsible for performing the addition operation and making the result available to the view.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.web.calculator.portlet.action;\r\n\r\nimport it.dontesta.labs.liferay.webservice.calculator.api.Calculator;\r\n\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(\r\n immediate = true,\r\n property = {\r\n \"javax.portlet.name=\" + CalculatorAppPortletKeys.CALCULATOR_SOAP_APP,\r\n \"mvc.command.name=\/calculator\/add-operation\"\r\n },\r\n service = MVCActionCommand.class\r\n)\r\npublic class AddOperationMVCActionCommand extends BaseMVCActionCommand {\r\n\r\n\r\n @Override\r\n protected void doProcessAction(\r\n ActionRequest actionRequest, ActionResponse actionResponse)\r\n throws Exception {\r\n\r\n\r\n _handleActionCommand(actionRequest);\r\n }\r\n\r\n\r\n private void _handleActionCommand(ActionRequest actionRequest) {\r\n try {\r\n int term1 = ParamUtil.getInteger(\r\n actionRequest, CalculatorAppWebKeys.ADD_OPERATION_TERM_1);\r\n\r\n\r\n int term2 = ParamUtil.getInteger(\r\n actionRequest, CalculatorAppWebKeys.ADD_OPERATION_TERM_2);\r\n\r\n\r\n int result = _calculator.add(term1, term2);\r\n\r\n\r\n actionRequest.setAttribute(\r\n CalculatorAppWebKeys.ADD_OPERATION_RESULT, result);\r\n }\r\n catch (SOAPFaultException soapfe) {\r\n SessionErrors.add(actionRequest, soapfe.getClass(), soapfe);\r\n }\r\n catch (WebServiceException wse) {\r\n SessionErrors.add(actionRequest, wse.getClass(), wse);\r\n }\r\n catch (Exception e) {\r\n SessionErrors.add(\r\n actionRequest, \"calculatorOperationError\", e.getMessage());\r\n }\r\n }\r\n\r\n @Reference(policyOption = ReferencePolicyOption.GREEDY)\r\n private Calculator _calculator;\r\n}<\/pre>\n<\/div>\nThe following figures show the simple calculator in action.<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/WebCalculatorSOAPInAction_1-1024x481.png\" "\\"Figure")
<\/a>Figure 7 - Example of the GUI for the division operation<\/p><\/div>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/WebCalculatorSOAPInAction_2-1024x657.png\" "\\"Figure")
<\/a>Figure 8 - Still division by zero! Example of the GUI in case of error obtained from the execution of the operation<\/p><\/div>\n
4 - Configuration of the JAX-WS API and CXF EndPoints<\/h2>\nEverything we have seen so far could not work until these two components are configured on the Liferay system:<\/div>\n<\/div>\n\n- CXF EndPoints<\/li>\n
- JAX-WS API<\/li>\n<\/ul>\n
<\/p>\n
This configuration should only be necessary if we decide to develop and publish SOAP services on our Liferay instance.<\/div>\n <\/p>\n
Even if we act as a SOAP client we must configure these two components so that the JAX-WS provider is correctly configured<\/strong> and we can use the JAX-WS API without incurring any error<\/span>.<\/div>\n <\/p>\n
The one shown in the figure is the error we would see if we did not configure the two components from the Liferay control panel.<\/div>\n<\/div>\n\n![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/GogoShellErrorJAX-WS-1024x199.png\" "\\"Figure")
<\/a>Figure 9 - Error shown when the JAX-WS API bridge has not been configured.<\/p><\/div>\n<\/div>\n
<\/div>\nThe following figures show the configurations for CXF and JAX-WS and in particular the Context Path<\/strong> (for more info you can see this https:\/\/portal.liferay.dev\/docs\/7-0\/tutorials\/-\/knowledge_base\/t\/jax-ws-and-jax-rs<\/a>).<\/div>\n<\/div>\n\n![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/ConfiguringCXFEndPoints-1024x283.png\" "\\"Figure")
<\/a>Figure 10 - CXF Endpoint configuration<\/p><\/div>\n
<\/p>\n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/ConfiguringJAX-WS-API-1024x442.png\" "\\"Figure")
<\/a>Figure 11 - JAX-WS API configuration<\/p><\/div>\n
<\/p>\n
If we want to be picky, we could run the services \"(objectClass=javax.xml.ws.spi.Provider)\"<\/em> command from Gogo Shell to verify the JAX-WS API bridge<\/strong> has been properly configured. You should get it in output when shown in the figure below.<\/p>\n <\/p>\n
<\/p>\n
\n
The goal is to make this service available to any application installed on our Liferay instance. We then structure our Liferay project in this way:<\/div>\n
<\/p>\n
- \n
- \nImplementation of the calculator-api<\/strong> module. This module defines the APIs that each application can invoke to use the services of arithmetic operations (addition, subtraction, division and multiplication);<\/div>\n<\/li>\n
- \n
Implementation of the calculator-service<\/strong> module. This module implements the APIs defined by the calculator-api module and acts as a client to the SOAP Calculator service;<\/div>\n<\/li>\n- \n
Implementation of the calculator-gogo-shell <\/strong>module. This module implements the Gogo Shell commands that use the APIs defined by the calculator-api module to perform the arithmetic operations;<\/div>\n<\/li>\n- \n
Implementation of the calculator-web<\/strong> module. This module implements a standard MVC portlet that uses the APIs defined by the calculator-api module to perform the arithmetic operations.<\/div>\n<\/li>\n<\/ol>\n<\/p>\n
<\/a>Figure 1 - Diagram of the relationships between the modules<\/p><\/div>\n<\/div>\n
<\/div>\nThe figure below shows the class diagram of the main classes of the various modules. In detail:<\/div>\n<\/p>\n
- \n
- \ncalculator-api<\/strong><\/div>\n
- \n
- \n<\/b>Calculator<\/em> is the interface that defines the arithmetic operations between two integers;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \n
calculator-service<\/strong><\/div>\n- \n
- \nCalculatorClientImpl<\/em> implements the APIs defined by the Calculator interface and acts as a client to the SOAP Calculator service;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \n
calculator-web<\/strong><\/div>\n- \n
- \nAddOperationMVCActionCommand<\/em>:\u00a0MVC Action Command of the Calculator Web Module for the request of the addition operation;<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
- \n
calculator-gogo-shell<\/strong><\/div>\n- \n
- \nCalculatorCommand<\/em>: Gogo Shell Commands of the Calculator Gogo Shell Module.<\/div>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
<\/p>\n
<\/a>Figure 2 - Class diagram<\/p><\/div>\n
<\/p>\n
1 -\u00a0Implementation of the SOAP client<\/h2>\n
In order to call the SOAP service we need to create the stubs that will be our interface that will allow us to interact with the remote service through the SOAP protocol.<\/div>\n<\/p>\n
To create all the java code we need, starting from the WSDL document, we usually use the wsimport<\/strong><\/a> tool.\u00a0Instead of using the command-line tool directly, we'll set up the project to use a Gradle task that does everything for us.<\/div>\n<\/div>\n<\/p>\n
The one shown below is the build.gradle file of the calculator-service module. The parts highlighted make it possible to use the Gradle gradle-jaxws-plugin<\/b> plugin.<\/div>\n<\/p>\n
The second block highlighted, sets the directory of WSDL documents<\/em> and the directory that will contain the java files generated from the WSDL document.\u00a0The WSDL document can be downloaded from the address http:\/\/www.dneonline.com\/calculator.asmx?WSDL<\/a> and saved in the directory indicated.<\/div>\n<\/div>\n\nbuildscript {\r\n repositories {\r\n maven {\r\n url \"https:\/\/plugins.gradle.org\/m2\/\"\r\n }\r\n }\r\n dependencies {\r\n classpath \"gradle.plugin.cz.swsamuraj:gradle-jaxws-plugin:0.6.1\"\r\n }\r\n}\r\n\r\napply plugin: \"cz.swsamuraj.jaxws\"\r\n\r\n\r\ndependencies {\r\n compileOnly group: \"com.liferay.portal\", name: \"com.liferay.portal.kernel\", version: \"4.4.0\"\r\n compileOnly group: \"org.osgi\", name: \"org.osgi.service.component.annotations\", version: \"1.3.0\"\r\n compileOnly project(\":modules:calculator:calculator-api\")\r\n}\r\n\r\n\r\njaxws {\r\n wsdlDir = 'src\/main\/resources\/META-INF\/wsdl'\r\n generatedSources = 'generatedsources\/src\/main\/java'\r\n}<\/pre>\n<\/div>\nAfter editing the build.gradle file you should (and after a refresh gradle project) the new Gradle tasks and in particular: wsImport<\/strong><\/div>\n<\/div>\n<\/div>\n\n<\/a>Figure 3 - New Gradle tasks added after configuring the gradle-jaxws-plugin plugin<\/p><\/div>\n<\/div>\n
<\/div>\nAt this point all that remains is to run the wsImport<\/em> task whose output will be the generation of the Java classes (stub). Now we have everything we need to be able to implement the SOAP client.<\/div>\n<\/div>\n\n<\/a>Figure 4 - Java classes generated by the Gradle wsImport task starting from the WSDL of the SOAP Calculator service.<\/p><\/div>\n
<\/div>\nThe code shown below is the implementation of the CalculatorClientImpl<\/strong> class that implements the Calculator interface and uses the stub classes to get the interface to SOAP services.<\/div>\n<\/p>\n
The _getService()<\/strong> method gets the reference to the CalculatorSOAP<\/strong> interface, the latter is used within all the methods that implement arithmetic operations.<\/div>\n<\/p>\n
Note that CalculatorClientImpl is a DS component<\/strong><\/a>, this will allow us to use the services of the Calculator interface with the simple @Reference<\/strong> annotation.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.webservice.calculator.client.soap;\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(immediate = true, property = {}, service = Calculator.class)\r\npublic class CalculatorClientImpl implements Calculator {\r\n\r\n\r\n @Override\r\n public int add(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().add(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int divide(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().divide(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int multiply(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().multiply(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n\r\n\r\n @Override\r\n public int subtract(int number1, int number2)\r\n throws CalculatorOperationException {\r\n try {\r\n return _getService().subtract(number1, number2);\r\n }\r\n catch (CalculatorServiceException cse) {\r\n throw new CalculatorOperationException(cse.getMessage(), cse);\r\n }\r\n }\r\n private CalculatorSoap _getService() throws CalculatorServiceException {\r\n if (Validator.isNull(_calculatorSoap)) {\r\n try {\r\n org.tempuri.Calculator calculator =\r\n new org.tempuri.Calculator();\r\n _calculatorSoap = calculator.getCalculatorSoap();\r\n }\r\n catch (WebServiceException wse) {\r\n throw new CalculatorServiceException(wse.getMessage(), wse);\r\n }\r\n return _calculatorSoap;\r\n }\r\n else {\r\n return _calculatorSoap;\r\n }\r\n }\r\n\r\n private CalculatorSoap _calculatorSoap;\r\n}<\/pre>\nFrom this moment we can use the Calculator service on any module. Who uses the service is absolutely abstract from the fact that the implementation uses external SOAP services.<\/p>\n
2 -\u00a0Implementation of Gogo Shell commands<\/h2>\n
Now let's see how to use the service to create a series of Gogo Shell commands that allow us to perform arithmetic operations.<\/div>\n<\/p>\n
The following code shows the class CalculatorCommand which uses the Calculator service referenced by the @Reference annotation and implement the arithmetic operations we defined in the Calculator interface.<\/div>\n<\/p>\n
I have reported only the most significant parts of the code that are highlighted.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.webservice.calculator.gogoshell;\r\n\r\nimport it.dontesta.labs.liferay.webservice.calculator.api.Calculator;\r\n\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(\r\n property = {\r\n \"osgi.command.function=add\",\r\n \"osgi.command.function=divide\",\r\n \"osgi.command.function=multiply\",\r\n \"osgi.command.function=subtract\",\r\n \"osgi.command.scope=calculator\"\r\n },\r\n service = Object.class\r\n)\r\npublic class CalculatorCommand implements Calculator {\r\n public int add(int number1, int number2)\r\n throws CalculatorOperationException {\r\n return getCalculatorService().add(number1, number2);\r\n }\r\n\r\n ...\r\n\r\n @Reference(policyOption = ReferencePolicyOption.GREEDY)\r\n private volatile Calculator _calculator;\r\n}<\/pre>\nOnce the module has been deployed, we have the commands to make the arithmetic operations available. Just connect to the Gogo Shell and try.<\/p>\n
<\/a>Figure 5 - Division by zero!<\/p><\/div>\n
<\/p>\n
<\/a>Figure 6 - Error in case of connectivity problems<\/p><\/div>\n
<\/h2>\n
3 -\u00a0Implementation of Calculator Web<\/h2>\n
We have seen how to use the Calculator service for Gogo Shell commands, why not implement a simple very basic web calculator?<\/div>\n<\/p>\n
In the class diagram of figure 2 we have seen that there are four MVC Command, one for each operation.<\/div>\n<\/p>\n
Following is the MVC Command code responsible for performing the addition operation and making the result available to the view.<\/div>\n<\/div>\n<\/div>\n\npackage it.dontesta.labs.liferay.web.calculator.portlet.action;\r\n\r\nimport it.dontesta.labs.liferay.webservice.calculator.api.Calculator;\r\n\r\n...\r\n\r\n\/**\r\n* @author Antonio Musarra\r\n*\/\r\n@Component(\r\n immediate = true,\r\n property = {\r\n \"javax.portlet.name=\" + CalculatorAppPortletKeys.CALCULATOR_SOAP_APP,\r\n \"mvc.command.name=\/calculator\/add-operation\"\r\n },\r\n service = MVCActionCommand.class\r\n)\r\npublic class AddOperationMVCActionCommand extends BaseMVCActionCommand {\r\n\r\n\r\n @Override\r\n protected void doProcessAction(\r\n ActionRequest actionRequest, ActionResponse actionResponse)\r\n throws Exception {\r\n\r\n\r\n _handleActionCommand(actionRequest);\r\n }\r\n\r\n\r\n private void _handleActionCommand(ActionRequest actionRequest) {\r\n try {\r\n int term1 = ParamUtil.getInteger(\r\n actionRequest, CalculatorAppWebKeys.ADD_OPERATION_TERM_1);\r\n\r\n\r\n int term2 = ParamUtil.getInteger(\r\n actionRequest, CalculatorAppWebKeys.ADD_OPERATION_TERM_2);\r\n\r\n\r\n int result = _calculator.add(term1, term2);\r\n\r\n\r\n actionRequest.setAttribute(\r\n CalculatorAppWebKeys.ADD_OPERATION_RESULT, result);\r\n }\r\n catch (SOAPFaultException soapfe) {\r\n SessionErrors.add(actionRequest, soapfe.getClass(), soapfe);\r\n }\r\n catch (WebServiceException wse) {\r\n SessionErrors.add(actionRequest, wse.getClass(), wse);\r\n }\r\n catch (Exception e) {\r\n SessionErrors.add(\r\n actionRequest, \"calculatorOperationError\", e.getMessage());\r\n }\r\n }\r\n\r\n @Reference(policyOption = ReferencePolicyOption.GREEDY)\r\n private Calculator _calculator;\r\n}<\/pre>\n<\/div>\nThe following figures show the simple calculator in action.<\/p>\n
<\/a>Figure 7 - Example of the GUI for the division operation<\/p><\/div>\n
<\/a>Figure 8 - Still division by zero! Example of the GUI in case of error obtained from the execution of the operation<\/p><\/div>\n
4 - Configuration of the JAX-WS API and CXF EndPoints<\/h2>\n
Everything we have seen so far could not work until these two components are configured on the Liferay system:<\/div>\n<\/div>\n- \n
- CXF EndPoints<\/li>\n
- JAX-WS API<\/li>\n<\/ul>\n
<\/p>\n
This configuration should only be necessary if we decide to develop and publish SOAP services on our Liferay instance.<\/div>\n<\/p>\n
Even if we act as a SOAP client we must configure these two components so that the JAX-WS provider is correctly configured<\/strong> and we can use the JAX-WS API without incurring any error<\/span>.<\/div>\n<\/p>\n
The one shown in the figure is the error we would see if we did not configure the two components from the Liferay control panel.<\/div>\n<\/div>\n\n<\/a>Figure 9 - Error shown when the JAX-WS API bridge has not been configured.<\/p><\/div>\n<\/div>\n
<\/div>\nThe following figures show the configurations for CXF and JAX-WS and in particular the Context Path<\/strong> (for more info you can see this https:\/\/portal.liferay.dev\/docs\/7-0\/tutorials\/-\/knowledge_base\/t\/jax-ws-and-jax-rs<\/a>).<\/div>\n<\/div>\n\n<\/a>Figure 10 - CXF Endpoint configuration<\/p><\/div>\n
<\/p>\n
<\/a>Figure 11 - JAX-WS API configuration<\/p><\/div>\n
<\/p>\n
If we want to be picky, we could run the services \"(objectClass=javax.xml.ws.spi.Provider)\"<\/em> command from Gogo Shell to verify the JAX-WS API bridge<\/strong> has been properly configured. You should get it in output when shown in the figure below.<\/p>\n
<\/p>\n
- \n
- \n
- \n
- \n
- \n
![\"Figure](\"https:\/\/www.dontesta.it\/wp-content\/uploads\/2019\/09\/GogoShellCheckJAX-WS-APIBridgeConfiguration-1024x191.png\")
<\/a>