Jdeveloper 12c - EJB with Rest WebService and Filtering Data Collection

In Jdeveloper 12c there is a support for Rest WebService based on EJB and its only for Java Service Facade not for Session Facade. You can create Rest WebService just right click on the Java Service Facade and in context menu click on Create RESTful Service.

In this blog entry I'm interested in constructing dynamic data collection based on the URI, query-string parameters and send Rest WebService response. Having sensible resource names or paths (e.g., /departments/10 instead of /api?type=departments&id=10) improves the clarity of what a given request does. Using URL query-string parameters is fantastic for filtering, sorting, limit, pagination or dynamic fields. Here HTTP GET method is used to retrieve (or read) a representation of a resource. Read more on Rest Webservice.

The resources are based on EJB Java Service Facade. I tried adding GET parameters (PathParam/QueryParam) to a collection in order to add functionality such as filtering, sorting, filetering fields, limit. I have written logic in Java Service Facade for few resources that looks as below:

HTTP Verb	Resource Naming (URI)	Entire Collection (e.g. departments)
GET	RestApplication/resources/model/departments	Return list of departments.
GET	RestApplication/resources/model/departments?offset=1	Return individual department object.
GET	RestApplication/resources/model/departments?limit=4&childValue=false	Return list of departments based on limit, if childValue passed as false response will not contains employeeList object.
GET	RestApplication/resources/model/departments?limit=4&childValue=false&orderBy=departmentId &orderType=DESC	Return list of departments based on ascending/descending order.
GET	RestApplication/resources/model/departments?limit=4&childValue=false &fields=departmentId,departmentName	Return list of departments with selected departments fields dynamically.
GET	RestApplication/resources/model/departments/20	Return department object by departementId.

You can download the sample workspace from here
[Runs with Oracle JDeveloper 12.1.2.0.0]

JDeveloper provides WADL supports to run the REST WebService, below are the examples.

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments - Return list of departments

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments?offset=1 - Return department object.

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments?limit=4&childValue=false - Return list of departments based on limit, if childValue passed as false response will not contains employeeList object.

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments?limit=4&childValue=false&orderBy=departmentId&orderType=DESC - Return list of departments based on ascending/descending order.

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments?limit=4&childValue=false&fields=departmentId,departmentName - Return list of departments with dynamic departments fields.

• GET http://127.0.0.1:7101/RestApplication/resources/model/departments/20 - Return department object by departementId.

Below Java Service Facade code explains how to create resources and filter the data collection for above scenarios.

@Path("model")
public class JavaServiceFacade {
    private final EntityManager em;
    private String XMLResponse;
    private String fields = null;
    private boolean childValue;

    public JavaServiceFacade() {
        final EntityManagerFactory emf = Persistence.createEntityManagerFactory("Model-1");
        em = emf.createEntityManager();
    }

    /**
     * @param childValue
     * @param offset
     * @param limit
     * @param fields
     * @param orderBy
     * @param orderType
     * @return
     */
    @GET
    @Produces("application/xml")
    @Path("/departments")
    public String getDepartmentsFindAll(@DefaultValue("true") @QueryParam("childValue") boolean childValue,
                                        @DefaultValue("0") @QueryParam("offset") int offset,
                                        @DefaultValue("0") @QueryParam("limit") int limit,
                                        @QueryParam("fields") String fields, @QueryParam("orderBy") String orderBy,
                                        @QueryParam("orderType") String orderType) {
        this.childValue = childValue;
        this.fields = fields;

        Query query = null;
        if (offset > 0) {
            query =
                em.createNamedQuery("Departments.findAll", Departments.class).setFirstResult(offset).setMaxResults(1);
            this.generateXMlResponse(query, false);
        } else if (orderBy != null) {
            String qlString = "select o from Departments o order by o." + orderBy;
            if (orderType != null)
                qlString += " " + orderType;
            query = em.createQuery(qlString, Departments.class).setMaxResults(limit);
            this.generateXMlResponse(query, false);
        } else {
            query = em.createNamedQuery("Departments.findAll", Departments.class).setMaxResults(limit);
            this.generateXMlResponse(query, false);
        }
        return this.XMLResponse;
    }

    /**
     * @param departmentId
     * @param fields
     * @param childValue
     * @return
     */
    @GET
    @Produces("application/xml")
    @Path("/departments/{departmentId}")
    public String getDepartmentById(@PathParam("departmentId") int departmentId, @QueryParam("fields") String fields,
                                    @DefaultValue("true") @QueryParam("childValue") boolean childValue) {
        this.childValue = childValue;
        this.fields = fields;
        Query query =
            em.createNamedQuery("Departments.ByDeptId", Departments.class).setParameter("bind_departmentId",
                                                                                        departmentId);
        this.generateXMlResponse(query, true);
        return this.XMLResponse;
    }

    /**
     * @param query
     * @param singleResult
     */
    public void generateXMlResponse(Query query, boolean singleResult) {
        if (singleResult == true) {
            List deptResultList = query.getResultList();
            if (deptResultList.size() > 0) {
                this.XMLResponse = "";
                Iterator deptListIterator = deptResultList.iterator();
                while (deptListIterator.hasNext()) {
                    this.XMLResponse += "";
                    Departments dept = (Departments) deptListIterator.next();
                    this.constructXML(dept.getClass(), dept, false);
                    if (this.childValue == true) {
                        List empList = dept.getEmployeesList1();
                        for (int j = 0; j < empList.size(); j++) {
                            Employees emp = empList.get(j);
                            this.XMLResponse += "";
                            this.constructXML(emp.getClass(), emp, true);
                            this.XMLResponse += "";
                        }
                    }
                    this.XMLResponse += "";
                }
                this.XMLResponse += "";
            }
        } else {
            Vector resultList = (Vector) query.getResultList();
            int deptSize = resultList.size();
            if (deptSize > 0) {
                this.XMLResponse = "";
                for (int i = 0; i < deptSize; i++) {
                    //  Object obj = resultList.elementAt(i);
                    this.XMLResponse += "";
                    Departments dept = (Departments) resultList.elementAt(i);
                    this.constructXML(dept.getClass(), dept, false);
                    if (this.childValue == true) {
                        List empList = dept.getEmployeesList1();
                        for (int j = 0; j < empList.size(); j++) {
                            Employees emp = empList.get(j);
                            this.XMLResponse += "";
                            this.constructXML(emp.getClass(), emp, true);
                            this.XMLResponse += "";
                        }
                    }
                    this.XMLResponse += "";
                }
                this.XMLResponse += "";
            }
        }
    }

    /**
     * @param clazz
     * @param obj
     * @param childValue
     */
    public void constructXML(Class clazz, Object obj, boolean childValue) {
        Class noparams[] = { };
        try {
            Field[] field = clazz.getDeclaredFields();
            for (int i = 0; i < field.length; i++) {
                String fieldName = field[i].getName();
                if (field[i].isAnnotationPresent(Column.class)) {
                    String methodName =
                        "get" + field[i].getName().toString().substring(0, 1).toUpperCase() +
                        field[i].getName().toString().substring(1);
                    Method method = clazz.getDeclaredMethod(methodName, noparams);
                    Object fieldValue = method.invoke(obj, null);

                    if (this.fields == null || childValue == true) {
                        this.XMLResponse += "<" + fieldName + ">" + fieldValue + "</" + fieldName + ">";
                    } else {
                        String columnNames[] = this.fields.split(",");
                        for (int j = 0; j < columnNames.length; j++) {
                            if (columnNames[j] != null) {
                                boolean colNamesExist = this.findFieldExists(Departments.class, columnNames[j]);
                                if (colNamesExist == true && columnNames[j].equals(fieldName))
                                    this.XMLResponse += "<" + fieldName + ">" + fieldValue + "</" + fieldName + ">";
                            }
                        }
                    }
                }
            }
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }

    /**
     *
     * @param clazz
     * @param fieldName
     * @return boolean
     */
    public boolean findFieldExists(Class clazz, String fieldName) {
        try {
            Field field = clazz.getDeclaredField(fieldName);
            if (field != null)
                return true;
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }
        return false;
    }
 
  /**
     * All changes that have been made to the managed entities in the
     * persistence context are applied to the database and committed.
     */
    private void commitTransaction() {
        final EntityTransaction entityTransaction = em.getTransaction();
        if (!entityTransaction.isActive()) {
            entityTransaction.begin();
        }
        entityTransaction.commit();
    }

    public Object queryByRange(String jpqlStmt, int firstResult, int maxResults) {
        Query query = em.createQuery(jpqlStmt);
        if (firstResult > 0) {
            query = query.setFirstResult(firstResult);
        }
        if (maxResults > 0) {
            query = query.setMaxResults(maxResults);
        }
        return query.getResultList();
    }

    public  T persistEntity(T entity) {
        em.persist(entity);
        commitTransaction();
        return entity;
    }

    public  T mergeEntity(T entity) {
        entity = em.merge(entity);
        commitTransaction();
        return entity;
    }
}

ADF Mobile - Programmatically call RestServiceAdapter for POST Request

In my previous blog entry we saw how to get Rest WebService based form values in managed bean programmatically. In this entry will see how RestServiceAdapter interface lets you trigger execution of web service operations without the need to create a web service data control or interact with it directly.

Below code will explain how to get REST WebService based form values in managed bean and programmatically call the RestServiceAdapter for the POST request . Already there is a documentation on this, but here I'm trying to explain the end to end scenario as mentioned in below steps.

1. Get the form values from departmentsIterator programmatically. 
2. Dynamically construct the response xml based on departmentsIterator.
3. Set the Rest WebService Connection with POST request option.

Take an example with mobile application having two screen. First screen consists of departments list and in second screen you can add new department for the Save button I have created the managed bean with actionListener method as below. 

public class DeptBean {
    public DeptBean() {
    }

    public void addDeptAction(ActionEvent actionEvent) {
        RestServiceAdapter restServiceAdapter = Model.createRestServiceAdapter();
        // Clear any previously set request properties, if any
        restServiceAdapter.clearRequestProperties();
        // Set the connection name
        restServiceAdapter.setConnectionName("RestServerEndpoint");
        restServiceAdapter.setRequestType(RestServiceAdapter.REQUEST_TYPE_POST);
        // Specify the type of request
        restServiceAdapter.addRequestProperty("Content-Type", "application/xml");
        restServiceAdapter.addRequestProperty("Accept", "application/xml; charset=UTF-8");
        // Specify the number of retries
        restServiceAdapter.setRetryLimit(0);
        // Set the URI which is defined after the endpoint in the connections.xml.
        // The request is the endpoint + the URI being set
        restServiceAdapter.setRequestURI("/EJBRestServiceDemo/jersey/EJBRestServiceDemo");

        ValueExpression ve =
            AdfmfJavaUtilities.getValueExpression("#{bindings.departmentsIterator.currentRow.dataProvider}",
                                                  Object.class);
        Object obj = ve.getValue(AdfmfJavaUtilities.getAdfELContext());
        if (obj instanceof VirtualJavaBeanObject) {
            try {
                VirtualJavaBeanObject vjbo = (VirtualJavaBeanObject)obj;
                String postData = this.constructXMlResponse(vjbo);
                response = restServiceAdapter.send(postData);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * Construct the XMLResponse based on the VirtualJavaBeanObject dynamically
     * @param vjbo
     * @return
     */
    public static String constructXMlResponse(VirtualJavaBeanObject vjbo) {
        String XMLResponse = "";
        if (vjbo.getAttributeInfoCount() > 0) {
            String xmlRootTag = getClassName(vjbo.getName());
            XMLResponse += "<" + xmlRootTag + ">";
            int count = vjbo.getAttributeInfoCount();
            for (int i = 0; i < count; i++) {
                AttributeInfo fieldName = vjbo.getAttributeInfo(i);
                XMLResponse +=
                        "<" + fieldName.name + ">" + vjbo.getAttribute(fieldName.name).toString() + "</" + fieldName.name +
                        ">";
            }
            XMLResponse += "</" + xmlRootTag + ">";
        }
        return XMLResponse;
    }


    /**
     * Get the class name with/without the package
     * @param className
     * @return
     */
    public static String getClassName(String className) {
        int firstChar = className.lastIndexOf('_') + 1;
        if (firstChar > 0) {
            className = className.substring(firstChar);
        }
        return className.toLowerCase();
    }
}

Note:- The GenericType is only exposed in SOAP data controls, so Rest Webservice data control can't be executed directly using AdfmfJavaUtilities.invokeDataControlMethod.

You can download the sample workspace from here.
[Runs with Oracle JDeveloper 11.1.2.4.0]

ADF Mobile - Get REST WebService based form values in managed bean

In my previous blog entry I went over "Get ADF Mobile Form values in managed bean using Accessor Iterator", In this entry we'll see how to get Rest WebService based form values in managed bean programmatically.

Below is one of the way to access Rest WebService based form values, here is the code below.

ValueExpression ve =
            AdfmfJavaUtilities.getValueExpression("#{bindings.editEmployeeIterator.currentRow.dataProvider}",
                                                  Object.class);
        Object obj = ve.getValue(AdfmfJavaUtilities.getAdfELContext());
  if (obj instanceof VirtualJavaBeanObject) {
            VirtualJavaBeanObject vjbo = (VirtualJavaBeanObject)obj;
            if (vjbo.getAttributeInfoCount() > 0) {
                int count = vjbo.getAttributeInfoCount();
                for (int i = 0; i > count; i++) {
                    AttributeInfo fieldName = vjbo.getAttributeInfo(i);
                    String fieldValue = vjbo.getAttribute(fieldName.name).toString();
                    System.out.println(fieldName.name + " :" + fieldValue);
                }
            }
        }

ADF Mobile With EJB Restful Web Service

This article is the continuation of my previous article on Configuring EJB with Restful Web Service in ADF. Here will see how to integrate EJB Restful Web Service with ADF mobile.

Application screen looks like below when it is deployed and run on the Android Device/Emulator. In the below screen Department list will be displayed.

Clicking on any department will take you to the selected Department details page, edit the details and click on the Save button to submit the data. Clicking on delete button will delete the current department.

From Department List screen, click on add button to add the new record. Enter the details and click on Save button to submit the data.

After the below actions, updated department result page will be displayed as shown below.

You can download the sample workspace from here
[Runs with Oracle JDeveloper 11.1.2.4.0 + HR Schema]

Implementation Steps

Create an ADF Mobile Application, the application consists of two projects. Application Controller project of Application LifeCycle, Listeners, Device Features DataControl and ViewController project contains mobile features content like AMX Files, Task Flows and DataControl.

In Application Controller project, create a Departments.java file and add the below code.

public class Departments {
    private BigDecimal departmentId;
    private String departmentName;
    private BigDecimal locationId;
    private BigDecimal managerId;

    public Departments() {
        super();
    }

    public Departments(BigDecimal departmentId, String departmentName, BigDecimal locationId, BigDecimal managerId) {
        this.departmentId = departmentId;
        this.departmentName = departmentName;
        this.locationId = locationId;
        this.managerId = managerId;
    }

    public void setDepartmentId(BigDecimal departmentId) {
        this.departmentId = departmentId;
    }

    public BigDecimal getDepartmentId() {
        return departmentId;
    }

    public void setDepartmentName(String departmentName) {
        this.departmentName = departmentName;
    }

    public String getDepartmentName() {
        return departmentName;
    }

    public void setLocationId(BigDecimal locationId) {
        this.locationId = locationId;
    }

    public BigDecimal getLocationId() {
        return locationId;
    }

    public void setManagerId(BigDecimal managerId) {
        this.managerId = managerId;
    }

    public BigDecimal getManagerId() {
        return managerId;
    }
}

Create DepartmentsDC.java file and add the below code, create DataControl based on DepartmentsDC file

public class DepartmentsDC {
    public DepartmentsDC() {
        super();
    }

    public Departments ediDepartment(BigDecimal departmentId, String departmentName, BigDecimal locationId,
                                     BigDecimal managerId) {
        return new Departments(departmentId, departmentName, locationId, managerId);
    }

    public Departments addDepartment() {
        BigDecimal defaultVal = new BigDecimal("0");
        return new Departments(defaultVal, "", defaultVal, defaultVal);
    }
}

In the New Gallery expand the General - XML nodes and select XML Schema and click OK, enter Departments.xsd in File Name field and the following attributes as shown in below image.

In the New Gallery expand the General - Connection nodes and select URL Connection and click OK, enter the URL Endpoint details, You can download Configuring EJB with Restful Web Service in ADF from my previous article.

Note: - Next create a URL Service Data Control from - http://IpAddress:7101/EJBRestService/jersey/EJBRESTService api with HTTP Methods: GET, PUT, POST, DELETE.

In the New Gallery expand the General - Data Control nodes and select URL Service Data Control and click OK and enter the details to create the GET method

In the New Gallery expand the General - Data Control nodes and select URL Service Data Control and click OK and enter the details to create the POST method.

In Create URL Service Data Control wizard - step 3 of 5, specify the XSD url which we created earlier.

In the New Gallery expand the General - Data Control nodes and select URL Service Data Control and click OK and enter the details to create the PUT method.

In Create URL Service Data Control wizard - step 3 of 5, specify the XSD url which we created earlier.

In the New Gallery expand the General - Data Control nodes and select URL Service Data Control and click OK and enter the details to create the DELETE method.

In Create URL Service Data Control wizard - step 3 of 5, enter the departmentId value as 0.

Next open the DataControls.dcx file and change the Definition id values to looks like below.

In ViewController project. Locate and expand the Application Sources folder, then expand the META-INF folder. You will see the adfmf-feature.xml file, click on the adfmf-feature.xml file to launch the Feature editor. Add a new feature by clicking the green plus sign on the Features table near top of the editor this will launch the new Create ADF Mobile Feature dialog, modify the values as shown below.

In the Features table, select the newly created feature Departments. Under the Features table, click the Content tab, and locate the Content table. Notice that the content item Departments.1 is created by default. Next add a new file by clicking the green plus sign and select taskflow option, this will launch the new Create ADF Mobile Task Flow dialog, modify the value as shown below.

Click on the DepartmentsTaskflow.xml to open the file in taskflow editor and follow the below steps.

• Create three views and name them as deptList, deptAdd and deptEdit respectively
• Draw the control flow case from deptList to addDept and Outcome as "add"
• Draw the control flow case from deptList to editDept and Outcome as "edit" 
• From DataControl palette drag and drop getDepartmentsFindAll and drop as method-call
• Draw the control flow case from getDepartmentsFindAll method-call to deptList and Outcome as "getDepartmentsFindAll"
• Draw the control flow case from addDept to getDepartmentsFindAll method-call and Outcome as "list"
• Draw the control flow case from editDept to getDepartmentsFindAll method-call and Outcome as "list"

DepartmentsTaskflow.xml will looks as shown below diagram.

Double click on deptList view will launch Create ADF Mobile AMX Page dialog, in page facets select Header and Secondary Action. Go to source tab and follow the below steps:

• In Header facet, amx:outputText set the value as "Dept List"
• In Secondary Action facet, for amx:commandButton modify the values text: Add, action: add
• From DC palette drag and drop EJBService->getDepartmentsFindAll()->Return->departmentss->departments->ADF Mobile List View and select the default options
• In amx:Item, set the action as "edit"
• Inside amx:Item set the setPropertyListener as shown below

Note:- Created the DataControl DepartmentsDC with addDepartment and editDepartment methods, so that the type casting the ADF form values to departments object will be easy.

Double click on deptAdd view will launch Create ADF Mobile AMX Page dialog, in page facets select Header, Primary Action. Go to source tab and follow the below steps:

• In Header facet, amx:outputText set the value as "Add Dept"
• In Primary Action facet, for amx:commandButton modify the values text: Back, action: __back
• From DC palette drag and drop DepartmentsDC->addDepartment->Departments->Form as ADF Mobile Form.
• Go to bindings and add the following attributesValues, departmentId, departmentName, locationId, managerId as shown below.

• From DC palette drag and drop postDepartments->Method as ADF Mobile Button, set name as "Save", action as "list" and set the setPropertyListener as shown below 

Double click on deptAdd view will launch Create ADF Mobile AMX Page dialog, in page facets select Header, Primary, Secondary Action. Go to source tab and follow the below steps:

• In Header facet, amx:outputText set the value as "Edit Dept"
• In Primary Action facet, for amx:commandButton modify the values text: Back, action: __back
• In Secondary Action facet,  from DC palette drag and drop EJBService->deleteDepartments->Method as ADF Mobile Button, set action as "list". In Edit Action Binding wizard mention the parameter for departmentId as #{pageFlowScope.departmentId}
• From DC palette drag and drop DepartmentsDC->editDepartment->Departments->Form as ADF Mobile Form and in edit action binding wizard mention the parameters as shown below

• Go to bindings and add the following attributesValues, departmentId, departmentName, locationId, managerId as shown below.

• From DC palette drag and drop putDepartments->Method as ADF Mobile Button, set name as "Save", action as "list" and set the setPropertyListener as shown below.

Configuring EJB with Restful Web Service in ADF

In current JDeveloper we can expose EJB's as Web Service, however this will be a SOAP based web service. In this article will discuss on configuring EJB with restful web service using jersey support. This article provides an example of building a complete RESTful API using the different HTTP methods:

• GET to retrieve data
• POST to add data
• PUT to update data
• DELETE to delete data

You can download the sample workspace from here
[Runs with Oracle JDeveloper 11.1.2.3.0 + HR Schema]

Implementation Steps:-

Create a EJB project, then create the DEPARTMENT JPA/EJB 3.0 Entity using the"Entities from tables" EJB wizard, create a Stateless Session bean and select Departments JPA Entity to generates façade methods.

Open the Departments entity and annotate with @XmlRootElement, when a top level class or an enum type is annotated with the @XmlRootElement annotation, then its value is represented as XML element in an XML document. Basically this allow ADF to convert this object directly to XML.JSON.

Add a new project ('REST Web Service Project') in the application and mention the name as WebService. Go to 'Project properties' > 'Dependencies' and add the Model project as a dependency.

Next add the supporting libraries to the Rest Web Service project, go to 'Project properties' > 'Libraries and Classpath'. Libraries are listed in the below screen shot, you can find the libraries in EJBRestService/libs folder.

Create and open EJBRestService java class, annotate with @Path("EJBRESTService") on class level. Click on the @Path notice on the left side yellow bulb will be appeared and click on the bulb to "Configure web.xml for jersey JAX-RS web services" as shown in below.

Now web.xml is created under WEB-INF folder. Open the file and replace with the below xml code.

<?xml version = '1.0' encoding = 'windows-1252'?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         version="2.5">
    <filter>
        <filter-name>JpsFilter</filter-name>
        <filter-class>oracle.security.jps.ee.http.JpsFilter</filter-class>
        <init-param>
            <param-name>enable.anonymous</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>JpsFilter</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>FORWARD</dispatcher>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
    </filter-mapping>
    <servlet>
        <servlet-name>jersey</servlet-name>
        <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
        <init-param>
            <param-name>com.sun.jersey.config.property.resourceConfigClass</param-name>
            <param-value>com.sun.jersey.api.core.PackagesResourceConfig</param-value>
        </init-param>
        <init-param>
            <param-name>com.sun.jersey.config.property.packages</param-name>
            <param-value>webservice</param-value>
        </init-param>
        <init-param>
            <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
            <param-value>true</param-value>
        </init-param>
        <!--load-on-startup>1</load-on-startup-->
    </servlet>
    <servlet-mapping>
        <servlet-name>jersey</servlet-name>
        <url-pattern>/jersey/*</url-pattern>
    </servlet-mapping>
    <ejb-local-ref>
        <ejb-ref-name>ejb/SessionEJBBean</ejb-ref-name>
        <ejb-ref-type>Session</ejb-ref-type>
        <local>model.SessionEJBLocal</local>
        <ejb-link>SessionEJB</ejb-link>
    </ejb-local-ref>
</web-app>

Points to be noticed from the above xml code are :

1. param-value under com.sun.jersey.config.property.packages tag - change the package name by your own package name used in the application.
2. Add the Ejb References 

Open the EJBRestService.java file and add the below code.

@Path("EJBRESTService")
public class EJBRestService {
    public EJBRestService() {
        super();
    }

    @GET
    @Produces(MediaType.APPLICATION_XML)
    public List getAllDepts() {
        List list = new ArrayList();
        try {
            Context ic = getInitialContext();
            SessionEJBLocal sessionEJB = (SessionEJBLocal)ic.lookup("java:comp/env/ejb/SessionEJBBean");
            for (Departments departments : (List)sessionEJB.getDepartmentsFindAll()) {
                list.add(departments);
            }
            ic.close();
        } catch (NamingException e) {
            e.printStackTrace();
        }
        return list;
    }

    @POST
    @Consumes(MediaType.APPLICATION_XML)
    public void persistDept(Departments departments) {
        try {
            Context ic = getInitialContext();
            SessionEJBLocal sessionEJB = (SessionEJBLocal)ic.lookup("java:comp/env/ejb/SessionEJBBean");
            sessionEJB.persistDepartments(departments);
            ic.close();
        } catch (NamingException e) {
            e.printStackTrace();
        }
    }

    @PUT
    @Consumes(MediaType.APPLICATION_XML)
    public void mergeDept(Departments departments) {
        try {
            Context ic = getInitialContext();
            SessionEJBLocal sessionEJB = (SessionEJBLocal)ic.lookup("java:comp/env/ejb/SessionEJBBean");
            sessionEJB.mergeDepartments(departments);
            ic.close();
        } catch (NamingException e) {
            e.printStackTrace();
        }
    }

    @DELETE
    @Path("{departmentId}")
    public void removeDept(@PathParam("departmentId")
        BigDecimal departmentId) {
        try {
            Context ic = getInitialContext();
            SessionEJBLocal sessionEJB = (SessionEJBLocal)ic.lookup("java:comp/env/ejb/SessionEJBBean");
            Departments departments = new Departments();
            departments.setDepartmentId(departmentId);
            sessionEJB.removeDepartments(departments);
            ic.close();
        } catch (NamingException e) {
            e.printStackTrace();
        }
    }

    private static Context getInitialContext() throws NamingException {
        InitialContext ic = new InitialContext(); // WebLogic Server 10.x connection details
        return ic;
    }
}

Now deploy/run the EJBRestService.java client in the Integrated Weblogic Server to test. Once client runs it will provide the Target Application WADL/Target URL in JDeveloper console, click on any link to run the service in HTTP Analyzer. Below screen shows the GET method accessed in HTTP Analyzer with result.

Note:- Put and Post method are not working with HTTP Analyzer, you might need to create java client/ADF application to test these methods.