Chapter 7 Security

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Let's consider a Web service with an interface containing multiple methods,

such as the one shown in Code Example 7.9, where you want different access pol 

icies for each method. For a service endpoint interface such as this you might

want to permit the following: Any client can browse the catalog of items available

for sale, only authorized customers for example, those clients who have set up

accounts can place orders, and only administrators can alter the catalog data. If

you implement the service with a Web tier endpoint, then each method has the

same protection because access control is the same for all methods that are bound

to the port at the endpoint's URL. To handle a service with an interface containing

multiple methods and different access policies, consider creating separate Web

services where each service handles a different set of authorization requirements. 

You have more flexibility if you implement the same Web service that has an

interface containing multiple methods with an EJB endpoint. By using an EJB

endpoint, you can set different authorization requirements for each method. See

the next section,  Controlling Access to Web Tier Endpoints,  and  Controlling

Access to EJB Tier Endpoints  on page 323.

public interface OrderingService extends java.rmi.Remote {

public Details getCatalogInfo(ItemType someItem) 

throws java.rmi.RemoteException;

public Details submitOrder(purchaseOrder po) 

throws java.rmi.RemoteException;

public void updateCatalog(ItemType someItem) 

throws java.rmi.RemoteException;

}

Code Example 7.9

Interface Methods Requiring Different Access Control

Keep in mind, however, that both Web and EJB tier endpoints can use pro 

grammatic APIs for finer grained security. If you are willing to write code for

access control, then both types of endpoints can be designed to handle the same

security capabilities. However, it is generally discouraged to embed security code

and use the programmatic security APIs in a component. A better approach keeps

the security policy externalized form the application code and uses the declarative

services with deployment descriptors.

E

If you require finer grained control for your access control policy, consider us 

ing an EJB endpoint, since it utilizes method level control.