Fast Way to Create a Web Service from an EJB3 Entity

Normally I would create an EJB session bean to expose my Entity queries from my Entity beans, but I thought it would be easier to just create a Java Service Facade and expose that as a web service as shown below.

1. In my project create an "Entity from table" using the new object gallery item in the EJB node. In this example we use the classic DEPT table.
2. Then edit your Dept entity to create another named query as shown below, as well as a toString method to display the bean.

....

@Entity
@NamedQueries({
@NamedQuery(name = "Dept.findAll", query = "select o from Dept o"),
@NamedQuery(name = "Dept.findByDeptno", query = "select o from Dept o where o.deptno = :deptno")
})
public class Dept
implements Serializable

...

@Override
public String toString()
{
return "Dept [" + deptno + ", " + dname + ", " + loc + "]";
}

3. From the EJB new object gallery select "Java Service Facade", in the wizard I only exposed these methods as well as a main method to test it with.

• public List getDeptFindAll() public
• public List getDeptFindByDeptno(Long deptno)

4. Add code to the main as follows to ensure the Java Service Facade works.

public static void main(String [] args)
{
final JavaServiceFacade javaServiceFacade = new JavaServiceFacade();
//  TODO:  Call methods on javaServiceFacade here...
List<Dept> deps = javaServiceFacade.getDeptFindAll();
for (Dept d: deps)
{
System.out.println(d);
}
}

5. Run it to verify it works well. Inside the persistence.xml I edited the following property (eclipselink.logging.level=INFO) to reduce the amount of output we get at runtime.

<persistence-unit name="Model-Test" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<class>model.Dept</class>
<properties>
<property name="eclipselink.jdbc.driver"
         value="oracle.jdbc.OracleDriver"/>
<property name="eclipselink.jdbc.url"
         value="jdbc:oracle:thin:@//beast.au.oracle.com:1523/linux11gr2"/>
<property name="eclipselink.jdbc.user" value="scott"/>
<property name="eclipselink.jdbc.password"
         value="3E20F8982C53F4ABA825E30206EC8ADE"/>
<property name="eclipselink.logging.level" value="INFO"/>
<property name="eclipselink.target-server" value="WebLogic_10"/>
</properties>
</persistence-unit>

Output:

... [EL Warning]: 2009-12-24 11:48:40.203--Failed to get InitialContext for MBean registration: javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file: java.naming.factory.initial
Dept [10, ACCOUNTING, NEW YORK]
Dept [20, RESEARCH, DALLAS]
Dept [30, SALES, CHICAGO]
Dept [40, OPERATIONS, BOSTON]

6. Now finally create a web service from the "JavaServiceFacade.java". To do this I simply invoked the "Create Java Web Service" from the object gallery or even easier use it's context menu option "Create Web Service".

Now you can test it using the "Test Web Service Wizard" option from the web service itself as now it is a Web Service as per step #6.

JDeveloper 11g R1 and PLSQL Web Services

Good to see PLSQL Web Services make it back into JDeveloper 11g R1 and I quickly gave it a test run today on some old but useful PLSQL code I previously used. By chance I stumbled upon the ability to test the web service in a browser once you have a running web service.

1. Right click on your created PLSQL Web Service and select Run
2. Wait for output as follows indicating the WS is running.

Warning: JMS queue 'weblogic.wsee.DefaultQueue' is not found, as a result, Web Service async responses via jms transport is not supported. If the target service uses JMS transport, the responses will not be able to come back. Run startup time: 6406 ms.
[Application WebServices deployed to Server Instance DefaultServer]

Target URL -- http://localhost:7101/WebServices-PLSQLWebServices-context-root/PLSQLWSPort
09/08/10 14:11:18 Web service PLSQLWS has been started on the embedded server

3. Copy and paste the URL into a browser and there is your web client.
4. Click on "Test Page"

REF CURSOR parameters in PLSQL Web Services

If you have ever tried to publish a PLSQL package as a Web Service that has a method signature as follows JDeveloper 10.1.3.x doesn't allow you.

procedure test1 (pRefCursor1 out sys_refcursor, prefCursor2 out sys_refcursor);

However the following does work for a function returning a refcursor.

function retrieve_emps return sys_refcursor;

If you press the "Why Not" button in the PLSQL Web Service dialog you get this message.

"Ref cursor type arguments are unsupported due to a JDBC limitation. Ref cursor types are only supported for use as the return type".

Due to this limitation if you have the luxury of developing the PLSQL from scratch you can simple use PLSQL tables to overcome this. So lets assume we have a collection defined as follows.

DROP TYPE employee_list;
DROP TYPE employee_obj;

CREATE OR REPLACE TYPE employee_obj AS OBJECT
( empno  NUMBER(4)
, ename  VARCHAR2(10)
, job    VARCHAR2(9)
, sal    NUMBER(7,2)
, deptno NUMBER(2)
);
/

create or replace TYPE employee_list AS TABLE OF employee_obj;

So now we can use a method signature as follows and this will work fine.

procedure copy_emps (pInEmps in employee_list, pOutEmps out employee_list);