I am preparing for the SCJEA examination and about to take the exam in 2 days times, I have read all the news in the JavaRanch and have consolidated all the mock questions from the site. I have try on all mock exam available in other sites but somehow I'm not so sure of the answer.
Almost all the questions are posted on JavaRanch, I pick them up and try on them but I do not know whether my answer is right. I would like to know of your answer so that I can figure if it make sense.
To those who have taken the exam, I will like your second opinions on these answers since most of the question is ambigous... thank ======================================================================
The following is the set of questions that I have try on
Q1: What is new feature in Java 2 security? (select one) 1. protection domain 2. Access Control List 3. digital signature 4. message digests
Q2: Normal lifecycle of a java application are 1) Problem Statement 2) OO Desgin 3) implementation 4) java app architecture 5) OO analysis
in what order? (select two) 1. 12345 2. 45213 3. 51423 4. 15423 5. 15243
ans: 4, 5
Q3: What is EJB's primary purpose? (select one) 1. Middleware independence 2. Platform independence 3. Language independence 4. Allow user to build middleware
Q4: What most accuratly describes the feature that JAVA 2 security provides? (select one) 1)Browers admins and users can grant access to websites and individuals to have system privileges browsers grant access to websites and individuals to have system privileges 2) Browser admins and users can grant access to individual classes to have system privileges
Q5: How do you find the origin of an applet (in JDK 1.0, 1.1 and 1.2)? 1) digital signatures. 2) Host name IP
Q6: How can hierachical databases be accessed? 1) JDBC 2) JNI 3) JTAPI 4) Object/relational mapping 5) JavaBlend
Q8: How does applet printing in 1.2 differ over 1.1 With 1.2 a applet trusted and signed can print to the client. ?
Q9: What does a good software architecture increase? (Choose the best answer) 1) robustness 2) scalability 3) complexity 4) maintenance
Q10: You are asked to convert an existing two-tier client-server application interacting with Oracle database to java. What input is most needed to study feasibilty of that project in java? any one. 1) er diagram (Entity-Relationship diagram) 2) application design 3) application code 4) list of gui objects
Ans: 2 (common sense?)
Q11: SSL. what does it encrypt? (choose one) 1) all tcp data but not TCP, IP or physical headers 2) physical data but not headers 3) ip data and not header 4) specific application fields but not protocol messages
Q12: What is OQL? 1) ad-hoc query standards for ODMBS. 2) Proprietary language to query ODBMS
Q13: How can an EJB component access a mainframe transaction processing system? (choose one) 1) Container that provides transaction processing 2) Container that provides database access
Q14: What is logging used for? (choose one) 1) tracking the activity of an individual 2) identifies an individual 3) determine the identity of an individual
Q15: How does a client locate an EJB instances? (choose one) 1) through JNDI 2) through RMI 3) through a home interface 4) through a remote interface
Q17: What two must be taken care of to ensure successful transition from development to production? (choose two) 1) Test on all web browsers and users 2) Use latest JDK 3) async communication between tiers
Ans: 1, 2
Q18: When would you use synchronous communication between Java architecture layers? 1) When the client needs to wait for an response 2) When the client doesn't need to wait for a response 3) When the network is not available
Ans : 1
Q19: What protocol will an applet use to communicate with a servlet? 1) sockets 2) RMI 3) HTTP 4) IIOP
Ans : 3
Q20: What must be taken care of during testing an Internet application from dev to depl on Intranet? (Choose two) 1) Test thru firewall 2) test with the slowest part of the n/w 3) load compatible jvms on client platforms 4) test in an isolated subnet
Ans: 1, 3
Q21: What does EJB propose to solve? (choose one) 1) Middleware independence 2) Platform independence 3) Language independence 4) Enables client to write Java middleware
Q22: When must you use async comm.? (choose one) 1) in a publish subscribe arch 2) when the network is reliable 3) when the network must be available 4) When you are developing transaction processing application
Ans : 1
Q23: What is the function of subscribe in publish/subscribe arch.? (choose one) 1) registers interest in an event 2) publishes to the arch. 3) subscribes to the architecture
Q24: Two advantages of publish/subscribe arch. (choose two) 1) it is scalable 2) allows decoupling of publishers and subscribers 3) it is fully object oriented 4) it is reusable
Ans: 1,2 since location independent.
Q25: When should you use HTTP with java. (choose one) 1) When using only object references. 2) Through a firewall
Q26: What is DMZ? (choose one) 1) A secure buffer between the the internet and intranet. 2) A semi-secure buffer between the internet and intranet. 3) A unsecure buffer between the internet and intranet.
Q27: In a 2-tier scenario with client talking SQL to Oracle database given the customer requirements, what additional information is required to decide the feasibility of whether app can be migrated to java or a new application written: 1) Application design 2) ER diagram of database schema
Q28: Given a UML notation representation: a rectangle with var rder (underlined) inside it? 1) an active "Order" object 2) instance of "Order" object 3) package containing "Order" object 4) node containing "Order" object
Q29: In both CORBA and RMI, a cause for large network traffic might be? (select most suitable answer) 1) NV lists 2) App data 3) Object wrappers 4) Object references
Ans: 4 since NVList can only apply to Corba not rmi.
Q30: Given a scenario of an existing application with 2 tier fat client accessing Oracle db through SQL, It may be less feasible to migrate to java if? (Choose the most suitable answer) 1) Volatile client app 2) Multiple client platforms 3) Experience in 4GL 4) Experience Database design 5) Experience in Smalltalk
Ans: 5 since have relearn Java language. Volatile means keep changing.
Q31: What are two advantages of publisher/subscribe? 1) scaleable 2) reusable 3) object-oriented
Q32: With respect to servlet which of the following are true? 1) Servlet can not access other Java objects on the server in which it resides 2) Servlet resides in the client 3) Servlet is multithreaded by default 4) Servlet is a request/response mechanism
Ans: 3, 4
Q34: A entity EJBObject class of an EJB implements 1) SessionBean 2) EntityBean 3) EJBHome 4) EJBObject
Ans: 2 since Entity beans implemention not referring to remote interface.
Q35: Facade pattern is best described as 1) The complex logic underlying is hidden in the (published) interface 2) To execute a chain of command in any order 4) To log the client interactions
Q36: What duties are performed by a Java Architect? (choose three) 1) Take an existing system to production 2) Define requirements for a new system 3) Develop a project plan which might include recommendations for training and mentoring the customer's staff. 4) Write stubs. 5) Evaluate a proposed architect put forward by a client.
Ans: 2, 3, 5 (Take an existing system to production ? What it means ?)
Q38: On whathat port number will you find HTTPS 1) 80 2) 81 3) 443 4) HTTPS uses named pipes
Q39: What happens when a business method is invoked on a bean that has timed out? 1.A new bean instance is created and the method is executed on it. 2.Remote exception is thrown 3.EJB Exception is thrown 4.ObjectNotFoundException is thrown 5.The implementation is vendor specific
Q40: Your J2EE solution that you implemented has been a huge success. The number of customers is almost 5 times what has been anticipated and performance is becoming an issue (select the best two) 1) Add more RAM to the 4 processor 4GB RAM Appserver 2) Add another AppServer set the webconnector to round-robin 3) Add a second network (LAN) card to the web server 4) Upgrade the database hardware
Ans: 2, 4
Q41: Two programs are there- and running concurrently. Both will select multiple rows from the table. No table updates can occur while the 2 programs are running. Which isolation can provide BEST performance while preventing conflicts? a) TRANSACTION-NO b) TRANSACTION-READ-UNCOMMITTED c) TRANSACTION-READ-COMMITTED d) TRANSACTION-REPEATABLE-READ e) TRANSACTION-SERIALIZABLE
Q42: What are the two features of JRMP A. It is Secure B. It is Connectionless C. It is Connectionbased D. It is used for Load balancing E. It is used for remote object communication
Ans: b, e
Q43: An UML diagram has a rectangle representing class A is connected by a solid line and a solid (dark) diamond near class A from class B. In Java implementation a.Class B will have a reference to Class A b.Class A will have a reference to Class B c.Class B has an aggregation relationship with Class A d.Class A has an composition relationship with Class B
Q44: In EJB for managing data consistency, Which database mechanisms provides data concurrency by preventing "lost updates?
The given choices are a) User security b) Buffer cache c) Log files d) Locking facilities e) Rollback segments
Q45: Which statement is true? A. Classes loaded into a browser from the local network are trusted B. classes loaded into a browser from remote sources are trusted if they are signed C. classed loaded into a browser from remote sources are trusted if they are in a signed jar file D. classes loaded from a jar file on a remote source can sometimes be trusted even if the jarfile is unsigned. E. classes loaded from a signed jarfile are trusted if the public key associated with the jarfile's signature is m marked as trusted in the keystore.
Q46: 1) Which one of the following statements describes the design that BEST leverages the J2EE architecture? a) Clients view applets in web browsers, servlets service the client requests on the server and interact with backend services such as databases. b) Clients install Swing components on their system which interact via RMI with EJBs on the server, EJBs interact with backend services such as databases. c) Clients view HTML in web browsers, JSP pages service the client requests and interact with EJBs on the server, EJBs interact with backend services such as databases. d) Clients view HTML in web browsers, CGI scripts service the client requests on the server and interact with EJBs on the server, EJBs interact with backend services such as databases.
Q47: .A reference to an EJB can be stored by a client for later use by: a) serializing the EJBObject to disk b) Adding the object to the server's pooled objects c) implementing a find for the bean d) storing the Handle of the EJB for the bean object
Q48: On a class diagram, a dashed line that has an open triangle on one end represents which of the following? a) association b) generalization c) Refinement d) dependency e) composition
Q50: .Given the choices below, which of the following are true regarding the ResourceBundle (Choose 2) 1) A ResourceBundle contains resources for a particular locale. 2) A ResourceBundle can convert between Unicode and other character encodings. 3) A ResourceBundle is a package that contains classes and interfaces for handling text in a local-sensitive way 4) New ResourceBundles can be added to a system without affecting the code that uses them 5) A swing application MUST always have a resourcebundle associated with it
Ans: 1, 4
Q51: When designing a new JAVA application architecture, JAVA architect should consider a) Optimize towards specific problem/platform b) Integrate with other application architecture c) 3-Tier should be there d) Presentation Logic and application logic should be Separate
Q52: SSL is used to encrypt a) All data b) Data of IP layer, no header c) Data of Physical layer, no header d) Data TCP/IP physical Layer, no header
Q53: What is virtual private network? a) Secure path through unsecured network b) Authenticated path through unsecured network
Q54: What factors we should consider in EXTRANET environment a) Low bandwidth b) Web servers c) Application servers d) Access control for each individual resources of INTRANET
Q55: What are the potential interference of firewall on IIOP ****************************************************************** (choose 2) a. port filtering b. address filtering c. load balancing (wrong) d. Nework Address Translation (NAT)
Q56: A company currently has a webserver and an application currently accessed via vt100 terminals on a second unix machine. Both machines are behind the company firewall which allows HTTP and HTTPS traffic. The company wishes to make the application available over the internet for use by external clients. (select the best solution) 1) Rewrite the application to use CGI, basing the cliet on html forms. 2) Use a commercial vt100 java applet client, use HTTP tunnelling on the webserver to redirect 443 to port 23 on the second unix machine. 3) Use a commerical screen-scraper application on the webserver to access the second machine. 4) Rewrite the application using EJB, JSP and Servlets.
Q57: You have successfully implemented a J2EE solution for a client. The client has become concerned that it's databases may be vunerable to malicious attack (hacking) what do you suggest as a solution. (select the best solution) 1) Tell him you have tested the code and can see no way in which access can be compromised. 2) Suggest creating a DMZ for the Web and Application Servers. 3) Suggest creating a DBZ for the Web Server. 4) Suggest a secure solution is possible by switching to SSL and issuing X500 certificates to ech client.
Q58: A Car Exhaust company is currently using leased lines to each of it's 300 nationwide depots with a 3270 client at each depot. The company urgently needs more than 1 terminal at each depot. (select the best solution) 1) Start collecting requirements for a J2EE Solution 2) Switch to VPN to solve immediate problem 3) Implement a screen scraper based application
Verbal Questions ===================================== Does The ejb sever creates a unique instance of that entity EJB object when EjbHome create method is called or reuse from bean pool ?