WCS Persistence Layer

The Persistence Layer

The persistence layer within the WebSphere Commerce architecture is defined by EJB

Types of enterprise beans

Entity Beans

Session Beans

Types of Entity Beans

Container-managed persistence

Bean-managed persistence

The Access Beans

Access beans are wrappers over the entity beans

Finding data by primary key

UserProfileAccessBean abUserProfile = new UserProfileAccessBean();

// set the primary key

abUserProfile.setInitKey_UserId(getUserId().toString());

//call getter to get the DisplayName.  Populate the access bean with data.

String myDisplayName = abUserProfile.getDisplayName();

Using a refreshcopyhelper method

Do not need to use the refreshCopyHelper() if we are using a getter method to retrieve specific data from the access bean.

Need to use it to explicitly tell the access bean to populate itself

UserProfileAccessBean abUserProfile = new UserProfileAccessBean();

abUserProfile.setInitKey_UserId(getUserId().toString());

abUserProfile.refreshCopyHelper();

Finding data using a finder method

Access beans may also provide specific finder methods for commonly needed "find" operations.

Returns an Enumeration of access beans that match the find criteria.

Will throw javax.ejb.ObjectNotFoundException if no data matches with the finder criteria

OrderAttributeValueAccessBean orderAttribute = new OrderAttributeValueAccessBean();

orderAttribute.findByOrderIdAndAttrName(orderId, attribute);

Creating new data using constructor

To create new data, we can initialize access bean constructor with one or more arguments.

//Create a new fullment center record.

FulfillmentCenterAccessBean fcab = new FulfillmentCenterAccessBean(ownerId, fflname);

Then set any additional data on the bean using the provided setters, and call the commitCopyHelper() method.

fcab.setInventoryOperationFlags(flags);  fcab.commitCopyHelper();

It is not required to call commitCopyHelper() to create the record using only the constructor.

Deleting a record using remove

To delete a record in the database using Access Beans, remove() method defined on the access bean's

EJB remote interface.

// Delete record using an AccessBean

try {

myAccessBean.getEJBRef().remove();

}

catch( ObjectNotFoundException e) {

//Exception

}

The data beans

 Data beans implement one or all of the following Java interfaces:

com.ibm.commerce.SmartDataBean.

com.ibm.commerce.CommandDataBean

com.ibm.commerce.InputDataBean (optional)

Instantiating databean in JSP

<wcbase:useBean id="offersDatabean" classname="com.shc.ecom.offercenter.databean.OffersDataBean">

<c:set value=“${offerId}” property=”offerId”/>

</wcbase:useBean>

Instantiating databean in Java

DataBeanManager.activate(data_bean, request, response)

How to create an access bean ?