Sun Certified Enterprise Architect for J2EE 5

1.What are the three primary roles in a web service interaction? (Choose three.)
A.Broker
B.Facade
C.Provider
D.Decorator
E.Requestor
F.Interceptor
Correct:A C E
2.A stock trading company is writing a new application for stock market forecasting. A significant portion of the work required by the business logic involves navigating through the persistent object model. As lead architect on this project, you have chosen JPA over EJB2 entity beans to implement these persistent objects. You have done this to maximize performance when navigating through the model. Why does JPA offer better performance for this task?
A.JPA guarantees referential integrity at the object level.
B.JPA allows the application to specify lazy or eager retrievals.
C.JPA simplifies the source code that implements the object model.
D.The guaranteed referential integrity in EJB2 entity beans is expensive.
Correct:B
3.A developer creates a Java web service to be used by consumers in an SOA. This SOA uses a UDDI service registry. How can the developer make the new service available to consumers?
A.deploy to the registry using JAXR
B.publish to the registry using JAXR
C.query the registry using JAX-RPC
D.target the registry using JAX-RPC
Correct:B
4.With the release of a new product line, there has been a significant increase in the volume of transactions on your web site. You need to scale your application and manage session failover. What is the best option for scalability?
A.add additional web servers and application servers
B.introduce a High Availability pair and utilize sticky sessions
C.add additional application servers and implement DNS round robin
D.add additional application servers and use clustered HttpSession
Correct:D
5.You are asked to architect an SOA solution that leverages Java web services. The architecture needs to be flexible and allow for the SOAP 1.1, SOAP 1.2, and REST implementations. Which Java EE technology should you use?
A.JAXP
B.JAXB
C.JAX-WS
D.JAX-RPC
Correct:C
6.You are architecting an online ordering application with these requirements: Users access the system over the Internet using HTML. An email message is sent to the user confirming the order. Users must log in and are validated using LDAP. The product catalog is stored in a relational database. All orders are logged to the internal fulfillment system. Orders must not be lost. Which Java EE technology should be used to send orders to the fulfillment system?
A.JNDI
B.JMS
C.JAX-WS
D.RMI-IIOP
Correct:B
7.An online sporting goods store's web application uses HTTPSession to store shopping carts. When the application is initially deployed, the business plan predicts only a few customers will access the site. Over time, the store projects a steady increase in volume. The deployment plan calls for a single web container in the initial deployment. As demand increases, the plan calls for multiple web containers on separate hardware with clustered HTTPSession objects. Which two principles will help the application meet the requirements and optimize performance? (Choose two.)
A.The application should store as much as possible in HTTPSession objects.
B.The application should NOT make frequent updates to HTTPSession objects.
C.The application should make coarse-grained updates to HTTPSession objects.
D.The application should create new HTTPSession objects instead of updating existing objects.
Correct:B C
8.You are writing a utility that searches for existing web services provided by large companies through UDDI. Your web site allows the user to input search criteria using event-driven, state-managed GUI screens, performs the search, and displays them in a formatted HTML page. Which technologies would you use for this application?
A.JSP and JAXB
B.JSF and JAXR
C.JSF and JAX-WS
D.JSP and JAX-WS
Correct:B
9.A company has a web service that provides the most recent price for stocks, mutual funds, and commodities. The company has the only web service that allows a person to check prices on all three financial assets with one call. Its system does not store this information but sends individual calls to each of the primary vendors for an asset and then aggregates the response to the requester. The company has committed to support a non-functional requirement (NFR) for performance that states it must process all requests within three seconds and each of the three vendors is obligated to support the NFR as dictated by the company. Where, in the message flow, is it appropriate to measure whether all the NFRs are met?
A.when a request is received and a response is sent to the requester
B.when a request is received, first call to vendor, last response from vendors, response is sent to a requester
C.when a requester sends a request, the request is received, each call to vendor, each response from vendor, requester receives response
D.when a request is received, each call to vendor, each response from a vendor, a response is sent to a requester
Correct:D
10.A Java web component, EJB component, or another web service can be a client to a web service. Which Java API can the client use to access the web service through a Service Endpoint Interface?
A.JAXB
B.JAXR
C.JDBC
D.JAX-WS
Correct:D
11.Which three are parts of a SOAP message? (Choose three.)
A.SOAP body
B.SOAP endpoint
C.SOAP headers
D.SOAP handlers
E.SOAP attachments
Correct:A C E
12.You are integrating with a single legacy Enterprise Information System. You are interested in the transaction management capabilities of the Java Connector Architecture. This new system needs the capability to invoke multiple operations against this single legacy system. These operations succeed together or fail together as a group. To which minimum level of transaction management are you going to set your resource adapter?
A.No transaction
B.Local transaction
C.Distributed transaction
D.Container Managed transaction
Correct:B
13.What is an advantage of XML over HTTP, as compared to SOAP over HTTP, for web services?
A.guaranteed delivery
B.more security options
C.smaller message size
D.strongly typed parameters
Correct:C
14.An application needs to invoke a service on a remote system over a low latency connection, and then wait for a response. Which two are best for this type of invocation? (Choose two.)
A.JMS topic
B.JMS queue
C.RMI over IIOP
D.synchronous web service
E.asynchronous web service
Correct:C D
15.Your new architecture needs to access the business logic of an Enterprise Information Solution (EIS). What are three benefits of using the Java Connector Architecture to connect to EIS instead of implementing a proprietary solution? (Choose three.)
A.security
B.performance
C.loose coupling
D.connection pooling
E.Common Client Interface
Correct:A D E
16.Your web application requires access to several different services, so you created a Service Locator class to be used by the UI developers on the team. New services with different interfaces are occasionally added. Unfortunately, the caching benefits of the Service Locator class are NOT being realized because a new instance of this class is being created in every backing bean method that requires a service. Which pattern should you apply to eliminate this problem?
A.Bridge
B.Singleton
C.Prototype
D.Factory Method
E.Business Delegate
Correct:B
17.What are two benefits of using the Value List Handler pattern? (Choose two.)
A.improves network performance
B.facilitates exposing existing services
C.provides an alternative to potentially inefficient EJB finders
D.facilitates post-processing across heterogeneous requests
E.provides a mechanism to support shared elements of composite views
Correct:A C
18.What are two capabilities of the Abstract Factory pattern? (Choose two.)
A.creates whole-part hierarchies
B.creates families of related objects
C.enforces dependencies between concrete classes
D.specifies the types of objects to create using a sample instance
E.separates the construction of a complex object from its representation
Correct:B C
19.A teenage fashion web site, includes a set of pages for displaying and browsing their catalog, as well as pages for making fashion suggestions that also display tables of catalog entries. Currently, the JSP code uses scriptlets that perform database SELECT statements and format the results in HTML tables. You have been hired to help reduce the maintenance overhead when either the look is modified or the database schema changes. Which two patterns, used together, do you apply to reduce this maintenance overhead? (Choose two.)
A.View Helper
B.Front Controller
C.Composite View
D.Data Access Object
Correct:A D
20.A new security feature has been requested for an existing web application with the following requirements: All requests must be logged to a secure database. Each request must be time-stamped with the start and completion times. Each request must contain the IP address of the client that made the request. Which pattern is most applicable for this new feature?
A.Strategy
B.Front Controller
C.Abstract Factory
D.Intercepting Filter
E.Model View Controller
Correct:D
21.Which two are benefits of using the Intercepting Filter pattern? (Choose two.)
A.allows the recombination of filters
B.provides efficient data sharing between filters
C.facilitates creating a generic command interface
D.facilitates common processing across heterogeneous requests
E.helps to minimize coupling between the presentation and business tiers
Correct:A D
22.You are building a subsystem that has several complex components, but you want to hide that complexity from the client code. Which pattern can you apply to hide this complexity?
A.Proxy
B.Bridge
C.Adaptor
D.Facade
E.Decorator
Correct:D
23.Some media players use a virtual proxy for image loading. What is the benefit of using a virtual proxy?
A.It controls access to the original object.
B.It defers creation of expensive objects until necessary.
C.It provides a local representation for an object in a different address space.
D.It is a replacement for a bare pointer that performs additional actions when an object is accessed.
Correct:B
24.Your company's web site is supported with a cluster of load-balanced web servers and a database server. To reduce expenses, your company must replace your current cluster of web servers with a single web server. All servers under consideration have the same specification. Which three items will be negatively impacted by this re-architecture? (Choose three.)
A.security
B.reliability
C.scalability
D.availability
E.manageability
F.maintainability
Correct:B C D
25.A company manufactures widgets for sale to distributors. Distributors call this company when they want to order more widgets. The company wants the distributors to send orders using XML documents over the Internet to reduce the number of data entry personnel needed. It has no control over the distributor's technologies. The company does not want the orders to impact the performance of the other users. You have been assigned the task of designing the new API. Which approach do you take?
A.design the API as a JMS queue
B.design the API as an RMI interface
C.design the API as a synchronous web service
D.design the API as an asynchronous web service
Correct:D
26.You have been tasked with improving the availability of an existing three-tier application. What is your first step in evaluating what changes should be made to the architecture to achieve the goal?
A.monitor network traffic between tiers
B.separate presentation from business logic
C.identify and document all single points of failure
D.cluster the presentation tier without session replication
Correct:C
27.Which non-functional requirement is a disadvantage for a two-tier architecture?
A.security
B.reliability
C.availability
D.manageability
Correct:D
28.A travel company is designing an application to allow customers to browse for information on any flights operating domestically and to place new reservations on any of those flights. The company makes the following assumptions: significant read volume, in terms of operations the customers will perform significant overlap, in the search criteria of customers simple processing of each customer browse/update request What advice can you give this company?
A.use a two-tier architecture (rich client directly accessing the database) because running copies of the business logic in each client provides significant advantages in terms of processing time per request
B.use a three-tier architecture (thin client -> application server -> database) because executing business logic remotely on a central location results in better performance per request
C.use a three-tier architecture (thin client -> application server -> database) because the shared business server allows them to cache information with high likelihood of cache hits, which reduces the load on the database
D.use a two-tier architecture (rich client directly accessing the database) because each client can operate on its own business objects, independently of others, which provides significant advantages from reduced latency due to synchronization
Correct:C
29.A company provides call center support for corporations world-wide. Each agent in the call center can be assigned to multiple call center customers. All of the company's customers use Windows-based user interfaces and it has just signed a new customer that uses a Java EE backend and wants a rich interface. The company is developing a user interface for the new customer with the following requirements: Customer service representatives (CSRs) must be able to work with minimal training on the application. CSRs must be able to switch between call center systems quickly. Screens must have a Windows "look and feel." 2000 agents spread across four locations must be able to use the system. What advice would you give this company on the user interface (UI)?
A.write the UI using JSP and JSTL
B.write the UI using JSPs with embedded scriptlets
C.write the UI using Ajax, accessing servlets directly
D.write the UI using Java Swing and distribute using JNLP
Correct:D
30.A travel company decides to re-architect their two-tier application (where each client ran its own copy of the application against a shared database) and hires you as their lead architect. You suggest they re-architect their application as a browser-based, three-tier solution: presentation, business logic, and persistence. You also suggest they deploy each of the three tiers on its own computer. Why is the three-tier solution more scalable than the two-tier solution?
A.Every client runs its own GUI application. Clients do not compete for resources for presentation purposes.
B.Clients share the same business logic tier. Client-specific objects can be stored centrally, optimizing access.
C.Every client shares the same business logic tier. Each client competes with each other for resources on that JVM.
D.Clients share the same business logic tier. Duplicate effort can be avoided by sharing objects, reducing the load on the database.
Correct:D