Which file defines all users on your system?Choose one:a. /etc/passwdb. /etc/usersc. /etc/passwordd. /etc/user.conf

Answer: aThe /etc/passwd file contains all the information on users who may log into your system. If a user account is not contained in this file, then the user cannot log in.Which two commands can you use to delete directories?A)rmB)rm-rfC)rmdirD)rdE)rd-rf

Answer(s): B, C - You can use rmdir or rm -rf to delete a directory. Answer a is incorrect, because the rm command without any specific flags will not delete a directory, it will only delete files. Answers d and e point to a non-existent command.Which partitioning tool is available in all distributions?A) Disk DruidB) fdiskC) Partition MagicD) FAT32E) System Commander

Answer(s): B - The fdisk partitioning tool is available in all Linux distributions. Answers a, c, and e all handle partitioning, but do not come with all distributions. Disk Druid is made by Red Hat and used in its distribution along with some derivatives. Partition Magic and System Commander are tools made by third-party companies. Answer d is not a tool, but a file system type. Specifically, FAT32 is the file system type used in Windows 98.Which partitions might you create on the mail server's hard drive(s) other than the root, swap, and boot partitions?[Choose all correct answers]A) /var/spool

B) /tmpC) /procD) /binE) /home

Answer(s): A, B, E - Separating /var/spool onto its own partition helps to ensure that if something goes wrong with the mail server or spool, the output cannot overrun the file system. Putting /tmp on its own partition prevents either software or user items in the /tmp directory from overrunning the file system. Placing /home off on its own is mostly useful for system re-installs or upgrades, allowing you to not have to wipe the /home hierarchy along with other areas. Answers c and d are not possible, as the /proc portion of the file system is virtual-held in RAM-not placed on the hard drives, and the /bin hierarchy is necessary for basic system functionality and, therefore, not one that you can place on a different partition.When planning your backup strategy you need to consider how often you will perform a backup, how much time the backup takes and what media you will use. What other factor must you consider when planning your backup strategy? _________

what to backupChoosing which files to backup is the first step in planning your backup strategy.What utility can you use to automate rotation of logs?Answer: logrotateThe logrotate command can be used to automate the rotation of various logs.In order to display the last five commands you have entered using the history command, you would type ___________ .

Answer: history 5The history command displays the commands you have previously entered. By passing it an argument of 5, only the last five commands will be displayed.What command can you use to review boot messages?Answer: dmesgThe dmesg command displays the system messages contained in the kernel ring buffer. By using this command immediately after booting

your computer, you will see the boot messages.What is the minimum number of partitions you need to install Linux?Answer: 2Linux can be installed on two partitions, one as / which will contain all files and a swap partition.What is the name and path of the main system log?Answer: /var/log/messagesBy default, the main system log is /var/log/messages.Of the following technologies, which is considered a client-side script?A) JavaScriptB) JavaC) ASPD) C++

Answer: A - JavaScript is the only client-side script listed. Java and C++ are complete programming languages. Active Server Pages are parsed on the server with the results being sent to the client in HTML

You need to see the last fifteen lines of the files dog, cat and horse. What command should you use?tail -15 dog cat horse

The tail utility displays the end of a file. The -15 tells tail to display the last fifteen lines of each specified file.Who owns the data dictionary?The SYS user owns the data dictionary. The SYS and SYSTEM users are created when the database is created.You routinely compress old log files. You now need to examine a log from two months ago. In order to view its contents without first having to decompress it, use the _________ utility.zcat

The zcat utility allows you to examine the contents of a compressed file much the same way that cat displays a file.You suspect that you have two commands with the same name

as the command is not producing the expected results. What command can you use to determine the location of the command being run?which

The which command searches your path until it finds a command that matches the command you are looking for and displays its full path.You locate a command in the /bin directory but do not know what it does. What command can you use to determine its purpose.whatis

The whatis command displays a summary line from the man page for the specified command.You wish to create a link to the /data directory in bob's home directory so you issue the command ln /data /home/bob/datalink but the command fails. What option should you use in this command line to be successful.Use the -F option

In order to create a link to a directory you must use the -F option.When you issue the command ls -l, the first character of the resulting display represents the file's ___________.type

The first character of the permission block designates the type of file that is being displayed.What utility can you use to show a dynamic listing of running processes? __________top

The top utility shows a listing of all running processes that is dynamically updated.Where is standard output usually directed?to the screen or display

By default, your shell directs standard output to your screen or display.You wish to restore the file memo.ben which was backed up in

the tarfile MyBackup.tar. What command should you type?tar xf MyBackup.tar memo.ben

This command uses the x switch to extract a file. Here the file memo.ben will be restored from the tarfile MyBackup.tar.You need to view the contents of the tarfile called MyBackup.tar. What command would you use?tar tf MyBackup.tar

The t switch tells tar to display the contents and the f modifier specifies which file to examine.You want to create a compressed backup of the users' home directories. What utility should you use?tar

You can use the z modifier with tar to compress your archive at the same time as creating it.What daemon is responsible for tracking events on your system?syslogd

The syslogd daemon is responsible for tracking system information and saving it to specified log files.You have a file called phonenos that is almost 4,000 lines long. What text filter can you use to split it into four pieces each 1,000 lines long?split

The split text filter will divide files into equally sized pieces. The default length of each piece is 1,000 lines.You would like to temporarily change your command line editor to be vi. What command should you type to change it?set -o vi

The set command is used to assign environment variables. In this case, you are instructing your shell to assign vi as your command line editor. However, once you log off and log back in you will return to the previously defined command line editor.What account is created when you install Linux?

root

Whenever you install Linux, only one user account is created. This is the superuser account also known as root.What command should you use to check the number of files and disk space used and each user's defined quotas?

repquota

The repquota command is used to get a report on the status of the quotas you have set including the amount of allocated space and amount of used space.In order to run fsck on the root partition, the root partition must be mounted asreadonly

You cannot run fsck on a partition that is mounted as read-write.In order to improve your system's security you decide to implement shadow passwords. What command should you use?pwconv

The pwconv command creates the file /etc/shadow and changes all passwords to 'x' in the /etc/passwd file.Bob Armstrong, who has a username of boba, calls to tell you he forgot his password. What command should you use to reset his command?passwd boba

The passwd command is used to change your password. If you do not specify a username, your password will be changed.The top utility can be used to change the priority of a running process? Another utility that can also be used to change priority is ___________?nice

Both the top and nice utilities provide the capability to change the priority of a running process.What command should you type to see all the files with an

extension of 'mem' listed in reverse alphabetical order in the /home/ben/memos directory.ls -r /home/ben/memos/*.mem

The -c option used with ls results in the files being listed in chronological order. You can use wildcards with the ls command to specify a pattern of filenames.

What key combination can you press to suspend a running job and place it in the background?ctrl-z

Using ctrl-z will suspend a job and put it in the background.The easiest, most basic form of backing up a file is to _____ it to another location.copy

The easiest most basic form of backing up a file is to make a copy of that file to another location such as a floppy disk.What type of server is used to remotely assign IP addresses to machines during the installation process?A) SMBB) NFSC) DHCPD) FTE) HTTP

C - You can use a DHCP server to assign IP addresses to individual machines during the installation process. Answers a, b, d, and e list legitimate Linux servers, but these servers do not provide IP addresses. The SMB, or Samba, tool is used for file and print sharing across multi-OS networks. An NFS server is for file sharing across Linux net-works. FTP is a file storage server that allows people to browse and retrieve information by logging in to it, and HTTP is for the Web.Which password package should you install to ensure that the central password file couldn't be stolen easily?A) PAMB) tcp_wrappers

C) shadowD) securepassE) ssh

C - The shadow password package moves the central password file to a more secure location. Answers a, b, and e all point to valid packages, but none of these places the password file in a more secure location. Answer d points to an invalid package.When using useradd to create a new user account, which of the following tasks is not done automatically.Choose one:a. Assign a UID.b. Assign a default shell.c. Create the user's home directory.d. Define the user's home directory.

c

The useradd command will use the system default for the user's home directory. The home directory is not created, however, unless you use the -m option.You want to enter a series of commands from the command-line. What would be the quickest way to do this?Choose Onea. Press enter after entering each command and its argumentsb. Put them in a script and execute the scriptc. Separate each command with a semi-colon (;) and press enter after the last commandd. Separate each command with a / and press enter after the last command

c

The semi-colon may be used to tell the shell that you are entering multiple commands that should be executed serially. If these were commands that you would frequently want to run, then a script might be more efficient. However, to run these commands only once, enter the commands directly at the command line.You attempt to use shadow passwords but are unsuccessful.

What characteristic of the /etc/passwd file may cause this?Choose one:a. The login command is missing.b. The username is too long.c. The password field is blank.d. The password field is prefaced by an asterisk.

c

The password field must not be blank before converting to shadow passwords.When you install a new application, documentation on that application is also usually installed. Where would you look for the documentation after installing an application called MyApp?Choose one:a. /usr/MyAppb. /lib/doc/MyAppc. /usr/doc/MyAppd. In the same directory where the application is installed.

c

The default location for application documentation is in a directory named for the application in the /usr/doc directory.What file would you edit in your home directory to change which window manager you want to use?A) XinitB) .xinitrcC) XF86SetupD) xstartE) xf86init

Answer: B - The ~/.xinitrc file allows you to set which window man-ager you want to use when logging in to X from that account.Answers a, d, and e are all invalid files. Answer c is the main X server configuration file.What command allows you to set a processor-intensive job to use less CPU time?A) ps

B) niceC) chpsD) lessE) more

Answer: B - The nice command is used to change a job's priority level, so that it runs slower or faster. Answers a, d, and e are valid commands but are not used to change process information. Answer c is an invalid command.While logged on as a regular user, your boss calls up and wants you to create a new user account immediately. How can you do this without first having to close your work, log off and logon as root?Choose one:a. Issue the command rootlog.b. Issue the command su and type exit when finished.c. Issue the command su and type logoff when finished.d. Issue the command logon root and type exit when finished.

Answer: bYou can use the su command to imitate any user including root. You will be prompted for the password for the root account. Once you have provided it you are logged in as root and can do any administrative duties.

There are seven fields in the /etc/passwd file. Which of the following lists all the fields in the correct order?Choose one:a. username, UID, GID, home directory, command, commentb. username, UID, GID, comment, home directory, commandc. UID, username, GID, home directory, comment, commandd. username, UID, group name, GID, home directory, commentAnswer: bThe seven fields required for each line in the /etc/passwd file are username, UID, GID, comment, home directory, command. Each of these fields must be separated by a colon even if they are empty.Which of the following commands will show a list of the files in your home directory including hidden files and the contents of all subdirectories?

Choose one:a. ls -c homeb. ls -aR /home/usernamec. ls -aF /home/usernamed. ls -l /home/username

Answer: bThe ls command is used to display a listing of files. The -a option will cause hidden files to be displayed as well. The -R option causes ls to recurse down the directory tree. All of this starts at your home directory.In order to prevent a user from logging in, you can add a(n) ________at the beginning of the password field.Answer: asterick

If you add an asterick at the beginning of the password field in the /etc/passwd file, that user will not be able to log in.You have a directory called /home/ben/memos and want to move it to /home/bob/memos so you issue the command mv /home/ben/memos /home/bob. What is the results of this action?Choose one:a. The files contained in /home/ben/memos are moved to the directory /home/bob/memos/memos.b. The files contained in /home/ben/memos are moved to the directory /home/bob/memos.c. The files contained in /home/ben/memos are moved to the directory /home/bob/.d. The command fails since a directory called memos already exists in the target directory.

Answer: aWhen using the mv command to move a directory, if a directory of the same name exists then a subdirectory is created for the files to be moved.Which of the following tasks is not necessary when creating a new user by editing the /etc/passwd file?Choose one:a. Create a link from the user's home directory to the shell the user will use.

b. Create the user's home directoryc. Use the passwd command to assign a password to the account.d. Add the user to the specified group.

Answer: aThere is no need to link the user's home directory to the shell command. Rather, the specified shell must be present on your system.You issue the following command useradd -m bobm But the user cannot logon. What is the problem?Choose one:a. You need to assign a password to bobm's account using the passwd command.b. You need to create bobm's home directory and set the appropriate permissions.c. You need to edit the /etc/passwd file and assign a shell for bobm's account.d. The username must be at least five characters long.

Answer: aThe useradd command does not assign a password to newly created accounts. You will still need to use the passwd command to assign a password.You wish to print the file vacations with 60 lines to a page. Which of the following commands will accomplish this? Choose one:a. pr -l60 vacations | lprb. pr -f vacations | lprc. pr -m vacations | lprd. pr -l vacations | lpr

Answer: aThe default page length when using pr is 66 lines. The -l option is used to specify a different l_________________________________________---

J2ee

What is J2EE?J2EE is an environment for developing and deploying enterprise applications. The J2EE platform consists of a set of services, application programming interfaces (APIs), and protocols that provide the functionality for developing multitier, web-based applications.What is the J2EE module?A J2EE module consists of one or more J2EE components for the same container type and one component deployment descriptor of that type.What are the components of J2EE application?A J2EE component is a self-contained functional software unit that is assembled into a J2EE application with its related classes and files and communicates with other components. The J2EE specification defines the following J2EE components:   Application clients and applets are client components.   Java Servlet and JavaServer PagesTM (JSPTM) technology components are web components.   Enterprise JavaBeansTM (EJBTM) components (enterprise beans) are business components.   Resource adapter components provided by EIS and tool vendors.What are the four types of J2EE modules?1. Application client module2. Web module3. Enterprise JavaBeans module4. Resource adapter moduleWhat does application client module contain?The application client module contains:--class files,--an application client deployment descriptor.Application client modules are packaged as JAR files with a .jar extension.What does web module contain?The web module contains:--JSP files,--class files for servlets,--GIF and HTML files, and--a Web deployment descriptor.Web modules are packaged as JAR files with a .war (Web ARchive) extension.

What is the difference between Session bean and Entity bean ?The Session bean and Entity bean are two main parts of EJB container.Session Bean--represents a workflow on behalf of a client--one-to-one logical mapping to a client.--created and destroyed by a client--not permanent objects--lives its EJB container(generally) does not survive system shut down--two types: stateless and stateful beansEntity Bean--represents persistent data and behavior of this data--can be shared among multiple clients--persists across multiple invocations--findable permanent objects--outlives its EJB container, survives system shutdown--two types: container managed persistence(CMP) and bean managed persistence(BMP)What is "applet"  ?A J2EE component that typically executes in a Web browser but can execute in a variety of other applications or devices that support the applet programming model.What is "applet container"  ?A container that includes support for the applet programming model.What is "application assembler" ?A person who combines J2EE components and modules into deployable application unitsWhat is "application client" ?A first-tier J2EE client component that executes in its own Java virtual machine. Application clients have access to some J2EE platform APIs.What is "application client container" ?A container that supports application client components.What is "application client module" ?A software unit that consists of one or more classes and an application client deployment descriptor.What is "application component provider" ?A vendor that provides the Java classes that implement components' methods, JSP page definitions, and any required deployment descriptors.

What is "application configuration resource file" ?An XML file used to configure resources for a Java Server Faces application, to define navigation rules for the application, and to register converters, Validator, listeners, renders, and components with the application.What is "archiving" ?The process of saving the state of an object and restoring it.What is "asant" ?A Java-based build tool that can be extended using Java classes. The configuration files are XML-based, calling out a target tree where various tasks get executed.What is "attribute"?A qualifier on an XML tag that provides additional information.What is authentication ?The process that verifies the identity of a user, device, or other entity in a computer system, usually as a prerequisite to allowing access to resources in a system. The Java servlet specification requires three types of authentication-basic, form-based, and mutual-and supports digest authentication.What is authorization ?The process by which access to a method or resource is determined. Authorization depends on the determination of whether the principal associated with a request through authentication is in a given security role. A security role is a logical grouping of users defined by the person who assembles the application. A deployer maps security roles to security identities. Security identities may be principals or groups in the operational environment.

authorization rule that determines who is permitted to access a Web resource collection.What is B2B ?B2B stands for Business-to-business.What is backing bean ?A JavaBeans component that corresponds to a JSP page that includes JavaServer Faces components. The backing bean defines properties for the components on the page and methods that perform processing

for the component. This processing includes event handling, validation, and processing associated with navigation.What is basic authentication ?An authentication mechanism in which a Web server authenticates an entity via a user name and password obtained using the Web application's built-in authentication mechanism.What is bean-managed persistence ?The mechanism whereby data transfer between an entity bean's variables and a resource manager is managed by the entity bean.What is bean-managed transaction ?A transaction whose boundaries are defined by an enterprise bean.What is binding (XML) ?Generating the code needed to process a well-defined portion of XML dataWhat is binding (JavaServer Faces technology) ?Wiring UI components to back-end data sources such as backing bean properties.What is build file ?The XML file that contains one or more asant targets. A target is a set of tasks you want to be executed. When starting asant, you can select which targets you want to have executed. When no target is given, the project's default target is executed.What is business logic ?The code that implements the functionality of an application. In the Enterprise JavaBeans architecture, this logic is implemented by the methods of an enterprise bean.What is business method ?A method of an enterprise bean that implements the business logic or rules of an application.What is callback methods ?Component methods called by the container to notify the component of important events in its life cycle.What is caller ?Same as caller principal.What is caller principal ?The principal that identifies the invoker of the enterprise bean method.

What is cascade delete ?A deletion that triggers another deletion. A cascade delete can be specified for an entity bean that has container-managed persistence.What is CDATA ?A predefined XML tag for character data that means "don't interpret these characters," as opposed to parsed character data (PCDATA), in which the normal rules of XML syntax apply. CDATA sections are typically used to show examples of XML syntax.What is certificate authority ?A trusted organization that issues public key certificates and provides identification to the bearer.What is client-certificate authentication ?An authentication mechanism that uses HTTP over SSL, in which the server and, optionally, the client authenticate each other with a public key certificate that conforms to a standard that is defined by X.509 Public Key Infrastructure.What is comment ?In an XML document, text that is ignored unless the parser is specifically told to recognize it.What is commit ?The point in a transaction when all updates to any resources involved in the transaction are made permanent.What is component contract ?The contract between a J2EE component and its container. The contract includes life-cycle management of the component, a context interface that the instance uses to obtain various information and services from its container, and a list of services that every container must provide for its components.What is component-managed sign-on ?A mechanism whereby security information needed for signing on to a resource is provided by an application component.What is connector ?A standard extension mechanism for containers that provides connectivity to enterprise information systems. A connector is specific to an enterprise information system and consists of a resource adapter and application development tools for enterprise information system connectivity. The resource adapter is plugged in to a container through its support for system-level contracts defined in the

Connector architecture.What is container-managed persistence ?The mechanism whereby data transfer between an entity bean's variables and a resource manager is managed by the entity bean's container.What is container-managed sign-on ?The mechanism whereby security information needed for signing on to a resource is supplied by the container.What is container-managed transaction ?A transaction whose boundaries are defined by an EJB container. An entity bean must use container-managed transactions.What is content ?In an XML document, the part that occurs after the prolog, including the root element and everything it contains.What is context attribute ?An object bound into the context associated with a servlet.What is context root ?A name that gets mapped to the document root of a Web application.

What is conversational state ?The field values of a session bean plus the transitive closure of the objects reachable from the bean's fields. The transitive closure of a bean is defined in terms of the serialization protocol for the Java programming language, that is, the fields that would be stored by serializing the bean instance.What is CORBA ?Common Object Request Broker Architecture. A language-independent distributed object model specified by the OMG.What is create method ?A method defined in the Interview Questions - Home interface and invoked by a client to create an enterprise bean.What is credentials ?The information describing the security attributes of a principal.What is CSS ?Cascading style sheet. A stylesheet used with HTML and XML documents to add a style to all elements marked with a particular tag,

for the direction of browsers or other presentation mechanisms.What is CTS ?Compatibility test suite. A suite of compatibility tests for verifying that a J2EE product complies with the J2EE platform specification.What is data ?The contents of an element in an XML stream, generally used when the element does not contain any subelements. When it does, the term content is generally used. When the only text in an XML structure is contained in simple elements and when elements that have subelements have little or no data mixed in, then that structure is often thought of as XML data, as opposed to an XML document.What is DDP ?Document-driven programming. The use of XML to define applications.What is declaration ?The very first thing in an XML document, which declares it as XML. The minimal declaration is . The declaration is part of the document prolog.What is declarative security ?Mechanisms used in an application that are expressed in a declarative syntax in a deployment descriptor.What is delegation ?An act whereby one principal authorizes another principal to use its identity or privileges with some restrictions.What is deployer ?A person who installs J2EE modules and applications into an operational environment.What is deployment ?The process whereby software is installed into an operational environment.What is deployment descriptor ?An XML file provided with each module and J2EE application that describes how they should be deployed. The deployment descriptor directs a deployment tool to deploy a module or application with specific container options and describes specific configuration requirements that a deployer must resolve.What is destination ?A JMS administered object that encapsulates the identity of a JMS

queue or topic. See point-to-point messaging system, publish/subscribe messaging system.What is digest authentication ?An authentication mechanism in which a Web application authenticates itself to a Web server by sending the server a message digest along with its HTTP request message. The digest is computed by employing a one-way hash algorithm to a concatenation of the HTTP request message and the client's password. The digest is typically much smaller than the HTTP request and doesn't contain the password.What is distributed application ?An application made up of distinct components running in separate runtime environments, usually on different platforms connected via a network. Typical distributed applications are two-tier (client-server), three-tier (client-middleware-server), and multitier (client-multiple middleware-multiple servers).What is document ?In general, an XML structure in which one or more elements contains text intermixed with subelements.What is Document Object Model ?An API for accessing and manipulating XML documents as tree structures. DOM provides platform-neutral, language-neutral interfaces that enables programs and scripts to dynamically access and modify content and structure in XML documents.What is document root ?The top-level directory of a WAR. The document root is where JSP pages, client-side classes and archives, and static Web resources are stored.What is DTD ?Document type definition. An optional part of the XML document prolog, as specified by the XML standard. The DTD specifies constraints on the valid tags and tag sequences that can be in the document. The DTD has a number of shortcomings, however, and this has led to various schema proposals. For example, the DTD entry says that the XML element called username contains parsed character data-that is, text alone, with no other structural elements under it. The DTD includes both the local subset, defined in the current file, and the external subset, which consists of the definitions contained in external DTD files that are referenced in the local subset using a parameter

entity.What is durable subscription ?In a JMS publish/subscribe messaging system, a subscription that continues to exist whether or not there is a current active subscriber object. If there is no active subscriber, the JMS provider retains the subscription's messages until they are received by the subscription or until they expire.What is EAR file ?Enterprise Archive file. A JAR archive that contains a J2EE application.What is ebXML ?Electronic Business XML. A group of specifications designed to enable enterprises to conduct business through the exchange of XML-based messages. It is sponsored by OASIS and the United Nations Centre for the Facilitation of Procedures and Practices in Administration, Commerce and Transport (U.N./CEFACT).What is EJB ?Enterprise JavaBeans.What is EJB container ?A container that implements the EJB component contract of the J2EE architecture. This contract specifies a runtime environment for enterprise beans that includes security, concurrency, life-cycle management, transactions, deployment, naming, and other services. An EJB container is provided by an EJB or J2EE server.What is EJB container provider ?A vendor that supplies an EJB container.What is EJB context ?A vendor that supplies an EJB container. An object that allows an enterprise bean to invoke services provided by the container and to obtain the information about the caller of a client-invoked method.What is EJB Home object ?An object that provides the life-cycle operations (create, remove, find) for an enterprise bean. The class for the EJB Home object is generated by the container's deployment tools. The EJB Home object implements the enterprise bean's Home interface. The client references an EJB Home object to perform life-cycle operations on an EJB object. The client uses JNDI to locate an EJB Home object.What is EJB JAR file ?A JAR archive that contains an EJB module.

What is EJB module ?A deployable unit that consists of one or more enterprise beans and an EJB deployment descriptor.What is EJB object ?An object whose class implements the enterprise bean's remote interface. A client never references an enterprise bean instance directly; a client always references an EJB object. The class of an EJB object is generated by a container's deployment tools.What is EJB server ?Software that provides services to an EJB container. For example, an EJB container typically relies on a transaction manager that is part of the EJB server to perform the two-phase commit across all the participating resource managers. The J2EE architecture assumes that an EJB container is hosted by an EJB server from the same vendor, so it does not specify the contract between these two entities. An EJB server can host one or more EJB containers.What is EJB server provider ?A vendor that supplies an EJB server.

What is element ?A unit of XML data, delimited by tags. An XML element can enclose other elements.What is empty tag ?A tag that does not enclose any content.What is enterprise bean ?A J2EE component that implements a business task or business entity and is hosted by an EJB container; either an entity bean, a session bean, or a message-driven bean.What is enterprise bean provider ?An application developer who produces enterprise bean classes, remote and Interview Questions - Home interfaces, and deployment descriptor files, and packages them in an EJB JAR file.What is enterprise information system ?The applications that constitute an enterprise's existing system for handling companywide information. These applications provide an information infrastructure for an enterprise. An enterprise information system offers a well-defined set of services to its clients. These services are exposed to clients as local or remote interfaces or both.

Examples of enterprise information systems include enterprise resource planning systems, mainframe transaction processing systems, and legacy database systems.What is enterprise information system resource ?An entity that provides enterprise information system-specific functionality to its clients. Examples are a record or set of records in a database system, a business object in an enterprise resource planning system, and a transaction program in a transaction processing system.What is Enterprise JavaBeans (EJB) ?A component architecture for the development and deployment of object-oriented, distributed, enterprise-level applications. Applications written using the Enterprise JavaBeans architecture are scalable, transactional, and secure.What is Enterprise JavaBeans Query Language (EJB QL) ?Defines the queries for the finder and select methods of an entity bean having container-managed persistence. A subset of SQL92, EJB QL has extensions that allow navigation over the relationships defined in an entity bean's abstract schema.What is an entity ?A distinct, individual item that can be included in an XML document by referencing it. Such an entity reference can name an entity as small as a character (for example, <, which references the less-than symbol or left angle bracket, <). An entity reference can also reference an entire document, an external entity, or a collection of DTD definitions.What is entity bean ?An enterprise bean that represents persistent data maintained in a database. An entity bean can manage its own persistence or can delegate this function to its container. An entity bean is identified by a primary key. If the container in which an entity bean is hosted crashes, the entity bean, its primary key, and any remote references survive the crash.What is entity reference ?A reference to an entity that is substituted for the reference when the XML document is parsed. It can reference a predefined entity such as < or reference one that is defined in the DTD. In the XML data, the reference could be to an entity that is defined in the local subset of the DTD or to an external XML file (an external entity). The DTD can also carve out a segment of DTD specifications and give it a name so

that it can be reused (included) at multiple points in the DTD by defining a parameter entity.What is error ?A SAX parsing error is generally a validation error; in other words, it occurs when an XML document is not valid, although it can also occur if the declaration specifies an XML version that the parser cannot handle. See also fatal error, warning.What is Extensible Markup Language ?XML.What is external entity ?An entity that exists as an external XML file, which is included in the XML document using an entity reference.What is external subset ?That part of a DTD that is defined by references to external DTD files.What is fatal error ?A fatal error occurs in the SAX parser when a document is not well formed or otherwise cannot be processed. See also error, warning.What is filter ?An object that can transform the header or content (or both) of a request or response. Filters differ from Web components in that they usually do not themselves create responses but rather modify or adapt the requests for a resource, and modify or adapt responses from a resource. A filter should not have any dependencies on a Web resource for which it is acting as a filter so that it can be composable with more than one type of Web resource.What is filter chain ?A concatenation of XSLT transformations in which the output of one transformation becomes the input of the next.What is finder method ?A method defined in the Interview Questions - Home interface and invoked by a client to locate an entity bean.What is form-based authentication ?An authentication mechanism in which a Web container provides an application-specific form for logging in. This form of authentication uses Base64 encoding and can expose user names and passwords