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1.Session and cookiesThe main difference between cookies and sessions is that cookies are stored in the user's browser, and sessions are not. This difference determines what each is best used for.

A cookie can keep information in the user's browser until deleted. If a person has a login and password, this can be set as a cookie in their browser so they do not have to re-login to your website every time they visit. You can store almost anything in a browser cookie. The trouble is that a user can block cookies or delete them at any time. If, for example, your website's shop-ping cart utilized cookies, and a person had their browser set to block them, then they could not shop at your website.

Sessions are not reliant on the user allowing a cookie. They work instead like a token allowing access and passing information while the user has their browser open. The problem with ses-sions is that when you close your browser you also lose the session. So, if you had a site re-quiring a login, this couldn't be saved as a session like it could as a cookie, and the user would be forced to re-login every time they visit.

2.HTTP headers Public

Content-Length Content-Type Content-Transfer-Encoding Allowed Date Expires Last-Modified Message-Id URI Version Derived-From Content-Language Cost Link Title

4.mysql join queries5.include and requireAll three are used to an include file into the current page. It is faster than include().If the file is not present, require(), calls a fatal error, while in include() does not.The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. It des not call a fatal error if file not exists. require_once() does the same as include_once(), but it calls a fatal error if file not exists.

6.Associated arry.Associate any key or index for tat array

7.Explain print_r8.MYSQl,php,apache versions.7.uploading in server8.Oops concept

9.explain abt PHP .ini. File

Modifying PHP Configuration File ( php.ini )

PHP stores all kinds of configuration in a file called php.ini.You can find this file in the directory where you installed PHP. Sometimes you will need to modify this file for example to use a PHP

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extension. I won't explain each and every configuration available just the ones that often need modification or special attention.

Some of the configurations are : register_globals

1. error_reporting and display_errors 2. extension and extension_path 3. session.save_path 4. max_execution_time

register_globals

Before PHP 4.2.0 the default value for this configuration is On and after 4.2.0 the default value is Off. The reason for this change is because it is so easy to write insecure code with this value on. So make sure that this value is Off in php.ini.

error_reporting and display_errors

Set the value to error_reporting = E_ALL during development but after production set the value to error_reporting = E_NONE .

The reason to use E_ALL during development is so you can catch most of the nasty bugs in your code. PHP will complain just about any errors you make and spit out all kinds of warning ( for example if you're trying to use an uninitialized variable ).

However, after production you should change the value to E_NONE so PHP will keep quiet even if there's an error in your code. This way the user won't have to see all kinds of PHP error message when running the script.

One important thing to note is that you will also need to set the value of display_erros to On. Even if you set error_reporting = E_ALL you will not get any error message ( no matter how buggy our script is ) unless display_errors is set to On.

extension and extension_path

PHP4 comes with about 51 extensions such as GD library ( for graphics creation and manipulation ), CURL, PostgreSQL support etc. These extensions are not turned on automatically. If you need to use the extension, first you need to specify the location of the extensions and then uncomment the extension you want.

The value of extension_path must be set to the directory where the extension is installed which is PHP_INSTALL_DIR/extensions, with PHP_INSTALL_DIR is the directory where you install PHP. For example I installed PHP in C:\Program Files\Apache Group\Apache2\php so the extensions path is :

extension_path = C:/Program Files/Apache Group/Apache2/php/extensions/

Don't forget to add that last slash or it won't work

After specifying the extension_path you will need to uncomment the extension you want to use. In php.ini a comment is started using a semicolon (;). As an example if you want to use GD library then you must remove the semicolon at the beginning of ;extension=php_gd2.dll to extension=php_gd2.dll

session.save_path

This configuration tells PHP where to save the session data. You will need to set this value to an existing directory or you will not be able to use session. In Windows you can set this value as session.save_path = c:/windows/temp/

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max_execution_time

The default value for max_execution_time is 30 ( seconds ). But for some scripts 30 seconds is just not enough to complete it's task. For example a database backup script may need more time to save a huge database.

If you think your script will need extra time to finish the job you can set this to a higher value. For example to set the maximun script execution time to 15 minutes ( 900 seconds ) you can modify the configuration as max_execution_time = 900

PHP have a convenient function to modify PHP configuration in runtime, ini_set(). Setting PHP configuration using this function will not make the effect permanent. It last only until the script ends.

11.cookie parameters ,size,maximum time limit.1) name - cookie name

    2) value - Optional parameter. Describes a value for cookie.     3) age - Optional parameter. Describes an age for cookie (in seconds). Default value is -1 (not persistent cookie)     3) path - Optional parameter: cookie path.     3) domain - Optional parameter: cookie domain

2) According to the draft specification issued by Netscape Communications, the limits regarding the size of cookie and space occupied by all cookies is:

4 KB per cookie maximum 300 total cookies, for a total of 1.2 Mbytes maximum 20 cookies accepted from a particular server or domain

12.to kill session,to kill variable1.seesion_destroy,unset.

13.urlencode,explode,implodereturn alphanumeric strings.Split a array by string,split ,Join array elements with a string ,

14.orderby,groupby.15.truncate,drop,delete diff

16.types of errors.E_PARSE—The script has a syntactic error and could not be parsed. This is a fatal

error.

E_COMPILE_ERROR—A fatal error occurred in the engine while compiling the script.

E_COMPILE_WARNING—A nonfatal error occurred in the engine while parsing the script.

E_CORE_ERROR—A fatal runtime error occurred in the engine.

E_CORE_WARNING—A nonfatal runtime error occurred in the engine.

E_ALL17.post and get difference18.subitting form without post,get

19.query for second largest no.Select Age From age E1 Where 3=(Select Count(*) From age E2 Where E1.Age<=E2.Age)

20.diff str &stristr

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string strstr ( string str1, string str2) this function search the string str1 for the first occurrence of the string str2 and returns the part of the string str1 from the first occurrence of the string str2. This function is case-sensitive and for case-insensitive search use stristr() function.

Who is the father of PHP and explain the changes in PHP versions? Rasmus Lerdorf is the father of PHP

How can we submit a form without a submit button? I can submit a form in many ways, for e.g.1. When user click on checkbox, or drop down2. When user click on radio button3. At the end of the form I will type “Click hereto submit” & link text to the processing file

What is the difference between mysql_fetch_object and mysql_fetch_array? mysql_fetch_array — Fetch a result row as an associative ARRAY, a numeric array, or bothmysql_fetch_object — Fetch a result row as an OBJECT

What is the difference between $message and $$message? A variable variable allows us to change the name of a variable dynamically.

How can we extract string ‘abc.com ‘ from a string ‘http://info@abc.com’ using regular expression of PHP? echo substr(”http://info@abc.com”,12,19);

How can we create a database using PHP and mysql? Functions in IMAP, POP3 AND LDAP? imap_body — Read the message bodyimap_check — Check current mailboximap_delete — Mark a message for deletion from current mailboximap_mail — Send an email message

How can I execute a PHP script using command line? Php -f <filename>

What is meant by nl2br()? Returns string with after inserting HTML line breaks before all newlines in a string

How can we encrypt and decrypt a data present in a mysql table using mysql? AES_ENCRYPT () and AES_DECRYPT ()

How can we encrypt the username and password using PHP? You can encrypt a password with the following Mysql>SET PASSWORD=PASSWORD("Password");We can encode data using base64_encode($string) and can decode using base64_decode($string);

What are the features and advantages of object-oriented programming? ne of the main advantages of OO programming is its ease of modification; objects can easily be modified and added to a system there by reducing maintenance costs. OO programming is also considered to be better at modeling the real world than is procedural programming. It allows for more complicated and flexible interactions. OO systems are also easier for non-technical personnel to understand and easier for them to participate in the maintenance and enhancement of a system because it appeals to natural human cognition patterns.For some systems, an OO approach can speed development time since many objects are standard across systems and can be reused. Components that manage dates, shipping, shopping carts, etc. can be purchased and easily modified for a specific system. What is the use of friend function?

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Friend functions Sometimes a function is best shared among a number of different classes. Such functions can be declared either as member functions of one class or as global functions. In either case they can be set to be friends of other classes, by using a friend specifier in the class that is admitting them. Such functions can use all attributes of the class whichnames them as a friend, as if they were themselves members of that class.A friend declaration is essentially a prototype for a member function, but instead of requiring an implementation with the name of that class attached by the double colon syntax, a global function or member function of another class provides the match.

What are the differences between public, private, protected, static, transient, final and volatile? Public: Public declared items can be accessed everywhere.Protected: Protected limits access to inherited and parent classes (and to the class that defines the item).Private: Private limits visibility only to the class that defines the item.Static: A static variable exists only in a local function scope, but it does not lose its value when program execution leaves this scope.Final: Final keyword prevents child classes from overriding a method by prefixing the definition with final. If the class itself is being defined final then it cannot be extended.

What is the functionality of the function htmlentities? This function is identical to htmlspecialchars() in all ways, except with htmlentities(), all characters which have HTML character entity equivalents are translated into these entities.

How can we get second of the current time using date function? $second = date("s");

What is meant by urlencode and urldocode? urlencode() returns the URL encoded version of the given string. URL coding converts special characters into % signs followed by two hex digits. For example: urlencode("10.00%") will return "10%2E00%25?. URL encoded strings are safe to be used as part of URLs.urldecode() returns the URL decoded version of the given string.

What is the difference between the functions unlink and unset? unlink() deletes the given file from the file system.unset() makes a variable undefined.

How can we register the variables into a session? We can use the session_register ($ur_session_var) function.

What is the maximum size of a file that can be uploaded using PHP and how can we change this? You can change maximum size of a file set upload_max_filesize variable in php.ini file

How can we increase the execution time of a PHP script? Set max_execution_time variable in php.ini file to your desired time in second.

How many ways can we get the value of current session id? session_id() returns the session id for the current session

How can we destroy the cookie? Set the cookie in past

What is the difference between ereg_replace() and eregi_replace()? eregi_replace() function is identical to ereg_replace() except that this ignores case distinction when matching alphabetic characters.eregi_replace() function is identical to ereg_replace() except that this ignores case distinction when matching alphabetic characters.

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What are the different functions in sorting an array? Asort,rsort,ksortHow can we know the count/number of elements of an array? Size,count

What is the PHP predefined variable that tells the What types of images that PHP supports? DirectorystdClass__PHP_Incomplete_Classexceptionphp_user_filter

How can we send mail using JavaScript?llocation=”mailto:mailid@domain.com?subject=”+tdata+”/MYFORM”;

What are the advantages of stored procedures, triggers, indexes? A stored procedure is a set of SQL commands that can be compiled and stored in the server. Once this has been done, clients don't need to keep re-issuing the entire query but can refer to the stored procedure. This provides better overall performance because the query has to be parsed only once, and less information needs to be sent between the server and the client. You can also raise the conceptual level by having libraries of functions in the server. However, stored procedures of course do increase the load on the database server system, as more of the work is done on the server side and less on the client (application) side.Triggers will also be implemented. A trigger is effectively a type of stored procedure, one that is invoked when a particular event occurs. For example, you can install a stored procedure that is triggered each time a record is deleted from a transaction table and that stored procedure automatically deletes the corresponding customer from a customer table when all his transactions are deleted.Indexes are used to find rows with specific column values quickly. Without an index, MySQL must begin with the first row and then read through the entire table to find the relevant rows. The larger the table, the more this costs. If the table has an index for the columns in question, MySQL can quickly determine the position to seek to in the middle of the data file without having to look at all the data. If a table has 1,000 rows, this is at least 100 times faster than reading sequentially. If you need to access most of the rows, it is faster to read sequentially, because this minimizes disk seeks.

What is the maximum length of a table name, database name, and fieldname in MySQL?

Database name- 64Table name -64Fieldname-64

What are the advantages/disadvantages of MySQL and PHP?

What is MIME? Multipurpose Internet Mail Extensions.WWW's ability to recognise and handle files of different types is largely dependent on the use of the MIME (Multipurpose Internet Mail Extensions) standard. The standard provides for a system of registration of file types with information about the applications needed to process them. This information is incorporated into Web server and browser software, and enables the automatic recognition and display of registered file types. …

What is PEAR in PHP? PEAR is short for "PHP Extension and Application Repository" and is pronounced just like the fruit. The purpose of PEAR is to provide:A structured library of open-sourced code for PHP usersA system for code distribution and package maintenanceA standard style for code written in PHPThe PHP Foundation Classes (PFC),

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The PHP Extension Community Library (PECL),A web site, mailing lists and download mirrors to support the PHP/PEAR communityPEAR is a community-driven project with the PEAR Group as the governing body. The project has been founded by Stig S. Bakken in 1999 and quite a lot of people have joined the project since then.

What is the default session time in PHP and how can I change it? The default session time in php is until closing of browser

What changes I have to done in PHP.ini file for file uploading? ; Whether to allow HTTP file uploads.file_uploads = On; Temporary directory for HTTP uploaded files (will use system default if not; specified).upload_tmp_dir = C:\apache2triad\temp; Maximum allowed size for uploaded files.upload_max_filesize = 2M

What are the differences between MySQL_fetch_array(), MySQL_fetch_object(), MySQL_fetch_row()? mysql_fetch_array — Fetch a result row as an associative array, a numeric array, or both.mysql_fetch_object ( resource result )Returns an object with properties that correspond to the fetched row and moves the internal data pointer ahead. Returns an object with properties that correspond to the fetched row, or FALSE if there are no more rowsmysql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.

Steps for the payment gateway processing? An online payment gateway is the interface between your merchant account and your Web site. The online payment gateway allows you to immediately verify credit card transactions and authorize funds on a customer’s credit card directly from your Web site. It then passes the transaction off to your merchant bank for processing, commonly referred to as transaction batching

List out different arguments in PHP header function?

void header ( string string [, bool replace [, int http_response_code]]) Explain MySQL optimization? First, one thing that affects all queries: The more complex permission system setup you have, the more overhead you get.If you do not have any GRANT statements done, MySQL will optimise the permission checking somewhat. So if you have a very high volume it may be worth the time to avoid grants. Otherwise, more permission check results in a larger overhead.

How can I get the only name of the current executing file?

$file = $_SERVER["SCRIPT_NAME"];echo $file;

Difference between Connect and Pconnect?Which should be closed explicitly?Difference between Session and Cookie?What is Mysql_Ping?Difference between set_cookie and Set_raw_cookie?Versions Of PHP/Mysql/Apache?Difference between PHP 4 and PHP 4?

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Difference between Get and Post?File Operations?How do use Payment Gateway in Projects? (5 to 6 questions related to payment gateway)

n commons, header() being used for page redirection, whereby a specific location being define. However header() can be use more than just that.

You can crate a virtual domain by using .htaccess file and you need to set some little things in control panel.

by using .htaccess file you can crate like as a under mention example.

.htaccess files are configuration files of Apache Server which provide a way to make configuration changes on a per-directory basis. A file, containing one or more configuration directives, is placed in a particular document directory, and the directives apply to that directory, and all subdirectories thereof.

1. On a fresh install, why does Apache have three config files - srm.conf, ac-cess.conf and httpd.conf? - The first two are remnants from the NCSA times, and generally you should be ok if you delete the first two, and stick with httpd.conf.

2. What’s the command to stop Apache? - kill the specific process that httpd is run-ning under, or killall httpd. If you have apachectl installed, use apachectl stop.

3. What does apachectl graceful do? - It sends a SIGUSR1 for a restart, and starts the apache server if it’s not running.

4. How do you check for the httpd.conf consistency and any errors in it? - apachectl configtest

5. When I do ps -aux, why do I have one copy of httpd running as root and the rest as nouser? - You need to be a root to attach yourself to any Unix port below 1024, and we need 80.

6. But I thought that running apache as a root is a security risk? - That one root process opens port 80, but never listens to it, so no user will actually enter the site with root rights. If you kill the root process, you will see the other kids disappear as well.

7. Why do I get the message "… no listening sockets available, shutting down"? - In Apache 2 you need to have a listen directive. Just put Listen 80 in httpd.conf.

8. How do you set up a virtual host in Apache? <VirtualHost www.techinterviews.com>    ServerAdmin admin@techinterviews.com    DocumentRoot /home/apache/share/htdocs/hostedsites    ServerName www.techinterviews.com    ErrorLog /home/apache/logs/error/hostedsites/error_log    TransferLog /home/apache/logs/access/hostedsites/access_log</VirtualHost>

9. What is ServerType directive? - It defines whether Apache should spawn itself as a child process (standalone) or keep everything in a single process (inetd). Keeping it in-etd conserves resources. This is deprecated, however.

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10. What is mod_vhost_alias? - It allows hosting multiple sites on the same server via simpler configurations.

11. What does htpasswd do? - It creates a new user in a specified group, and asks to specify a password for that user.

12. If you specify both deny from all and allow from all, what will be the default action of Apache? - In case of ambiguity deny always takes precedence over allow.

. List few features of object oriented programming.Object oriented programming features: Follows bottom up approach.Emphasis is on data.Programs are divided into objects.Functions and data are bound together.Communication is done through objects.Data is hidden.

2. List features of procedure oriented programming.Procedure oriented programming features:Follows top down approach.Emphasis is on procedure.Programs are divided into functions.Data moves around freely.

3. What are the basic concepts of OOPs?The following are the basic concepts of OOPs:Classes, Objects, Data abstraction and encapsulation, Polymorphism, Inheritance, Message Passing, and Dynamic Binding.

4. What is a class?Class is an entity which consists of member data and member functions which operate on the member data bound together.

5. What is an object?Objects are instances of classes. Class is a collection of similar kind of objects. When a class is created it doesn’t occupy any memory, but when instances of class is created i.e., when objects are created they occupy memory space.

6. What is data encapsulation?Wrapping up of member data and member functions together in a class is called data encapsulation.

7. What is data abstraction?Data abstraction refers to the act of providing only required features and hiding all the non-essential details for usage.

8. What are ADTs?ADTs stand for abstract data types. Classes which provide data abstraction are referred to as ADTs.

9. What is inheritance?The process of inheriting the properties of one object by another object is called inheritance.

10. What is polymorphism?The feature of exhibiting many forms is called polymorphism.

11. What are the steps involved in message passing?The following are the steps involved in message passing:Creating classes, creating objects, and creating communication between objects.

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12. What is dynamic binding?The feature that the associated code of a given function is not known till run time is called dynamic binding.

13. What are the advantages of OOP?Data hiding helps create secure programs.Redundant code can be avoided by using inheritance.Multiple instances of objects can be created.Work can be divided easily based on objects.Inheritance helps to save time and cost.Easy upgrading of systems is possible using object oriented systems.

14. Give an example for object based programming language.Ada is an example for object based programming language.

15. Write the features of object based programming language.Data hiding, data encapsulation, operator overloading and automatic initialization and clear up of objects are the important features exhibited by object based programming languages.

What is the difference between Information Hiding and Encapsulation?

Generally Encapsulation is often referred to as information hiding. Though the two terms are often used interchangeably, Information Hiding is really the result of Encapsulation, not a synonym for it. Both are distinct concepts.

Encapsulation makes it possible to separate an object’s implementation from its behavior - to restrict access to its internal data. This restriction allows certain details of an object’s behavior to be hidden. It allows us to create a “black box” and protects an object’s internal state from corruption by its user.

What is an Interface?

An interface is a contract & defines the requisite behavior of generalization of types.

An interface mandates a set of behavior, but not the implementation. Interface must be inherited. We can't create an instance of an interface.

An interface is an array of related function that must be implemented in derived type. Members of an interface are implicitly public & abstract.

An interface can inherit from another interface.

What is Sealed modifiers?

Sealed types cannot be inherited & are concrete.

Sealed modifiers can also be applied to instance methods, properties, events & indexes. It can't be applied to static members.

Sealed members are allowed in sealed and non-sealed classes.

What is Abstract Class?

Abstract class exists extensively for inheritance. We can't create an instance of an abstract class. Abstract type must be inherited.

Static, Value Types & interface doesn't support abstract modifiers.

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Static members cannot be abstract. Classes with abstract member must also be abstract.

What is New modifiers?

The new modifiers hides a member of the base class. C# supports only hide by signature.

What is Virtual keyword?

This keyword indicates that a member can be overridden in a child class. It can be applied to methods, properties, indexes and events.

What is Inheritance?

It provides a convenient way to reuse existing fully tested code in different context thereby saving lot of coding.

Inheritance of classes in C# is always implementation Inheritance.

What is Static Method?

It is possible to declare a method as Static provided that they don't attempt to access any instance data or other instance methods.What is Static field?

To indicate that a field should only be stored once no matter how many instance of the class we create.What is Class?

A Class is the generic definition of what an object is a template.

The keyword class in C# indicates that we are going to define a new class (type of object)

What is Object?

Object is anything that is identifiable as a single material item.

Can Struct be inherited?

No, Struct can't be inherited as this is implicitly sealed.

What is Virtual method?

Virtual Method has implementation & provide the derived class with the option to override it.

What is Abstract method?

Abstract method doesn't provide the implementation & forces the derived class to override the method.

What is Polymorphisms?

Polymorphism means one interface and many forms. Polymorphism is a characteristics of being able to assign a different meaning or usage to something in different contexts specifically to allow an entity such as a variable, a function or an object to have more than one

form.

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What's AJAX?

AJAX (Asynchronous JavaScript and XML) is a newly coined term for two powerful browser fea-tures that have been around for years, but were overlooked by many web developers until re-cently when applications such as Gmail, Google Suggest, and Google Maps hit the streets.

Asynchronous JavaScript and XML, or Ajax (pronounced "Aye-Jacks"), is a web development technique for creating interactive web applications using a combination of  XHTML (or HTML) and CSS for marking up and styling information.

(XML is commonly used, although any format will work, including preformatted HTML, plain text, JSON and even EBML).

The Document Object Model manipulated through JavaScript to dynamically display and inter-act with the information presentedThe XMLHttpRequest object to exchange data asynchronously with the web server.

In some Ajax frameworks and in some situations, an IFrame object is used instead of the XML-HttpRequest object to exchange data with the web server.

Like DHTML, LAMP, or SPA, Ajax is not a technology in itself, but a term that refers to the use of a group of technologies together. In fact, derivative/composite technologies based substan-tially upon Ajax, such as AFLAX, are already appearing.

Ajax applications are mostly executed on the user's computer; they can perform a number of tasks without their performance being limited by the network.

This permits the development of interactive applications, in particular reactive and rich graphic user interfaces.

Ajax applications target a well-documented platform, implemented by all major browsers on most existing platforms.

While it is uncertain that this compatibility will resist the advent of the next generations of browsers (in particular, Firefox), at the moment, Ajax applications are effectively cross-plat-form.

While the Ajax platform is more restricted than the Java platform, current Ajax applications ef-fectively fill part of the one-time niche of

Java applets: extending the browser with portable, lightweight mini-applications.

Ajax isn’t a technology. It’s really several technologies, each flourishing in its own right, com-ing together in powerful new ways. Ajax incorporates:

* standards-based presentation using XHTML and CSS;

* dynamic display and interaction using the Document Object Model;

* data interchange and manipulation using XML and XSLT; * asynchronous data retrieval using XMLHttpRequest;

* and JavaScript binding everything together.

Who’s Using Ajax ?

Google is making a huge investment in developing the Ajax approach.

All of the major products Google has introduced over the last year — Orkut, Gmail, the latest

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beta version of Google Groups, Google Suggest, and Google Maps — are Ajax applications.

(For more on the technical nuts and bolts of these Ajax implementations, check out these ex-cellent analyses of Gmail, Google Suggest, and Google Maps.) Others are following suit: many of the features that people love in Flickr depend on Ajax, and Amazon’s A9.com search engine applies similar techniques.

These projects demonstrate that Ajax is not only technically sound, but also practical for real-world applications. This isn’t another technology that only works in a laboratory. And Ajax ap-plications can be any size, from the very simple, single-function Google Suggest to the very complex and sophisticated Google Maps.

Who’s Using Ajax ?

Google is making a huge investment in developing the Ajax approach.

All of the major products Google has introduced over the last year — Orkut, Gmail, the latest beta version of Google Groups, Google Suggest, and Google Maps — are Ajax applications. (For more on the technical nuts and bolts of these Ajax implementations, check out these excellent analyses of Gmail, Google Suggest, and Google Maps.)

Others are following suit: many of the features that people love in Flickr depend on Ajax, and Amazon’s A9.com search engine applies similar techniques.

These projects demonstrate that Ajax is not only technically sound, but also practical for real-world applications. This isn’t another technology that only works in a laboratory. And Ajax ap-plications can be any size, from the very simple, single-function Google Suggest to the very complex and sophisticated Google Maps.

At Adaptive Path, we’ve been doing our own work with Ajax over the last several months, and we’re realizing we’ve only scratched the surface of the rich interaction and responsiveness that Ajax applications can provide.

Ajax is an important development for Web applications, and its importance is only going to grow. And because there are so many developers out there who already know how to use these technologies, we expect to see many more organizations following Google’s lead in reap-ing the competitive advantage Ajax provides.

The biggest challenges in creating Ajax applications are not technical.

The core Ajax technologies are mature, stable, and well understood. Instead, the challenges are for the designers of these applications: to forget what we think we know about the limita-tions of the Web, and begin to imagine a wider, richer range of possibilities

Should I consider AJAX?

AJAX definitely has the buzz right now, but it might not be the right thing for you. AJAX is lim-ited to the latest browsers, exposes browser compatibility issues, and requires new skill-sets for many.

There is a good blog entry by Alex Bosworth on AJAX Mistakes which is a good read before you jump full force into AJAX.

On the other hand you can achieve highly interactive rich web applications that are responsive and appear really fast.

While it is debatable as to whether an AJAX based application is really faster, the user feels a sense of immediacy because they are given active feedback while data is exchanged in the background.

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If you are an early adopter and can handle the browser compatibility issues, and are willing to learn some more skills, then AJAX is for you.

It may be prudent to start off AJAX-ifying a small portion or component of your application first. We all love technology, but just remember the purpose of AJAX is to enhance your user's expe-rience and not hinder it.

Does AJAX work with Java?

Absolutely. Java is a great fit for AJAX! You can use Java Enterprise Edition servers to generate AJAX client pages and to serve incoming AJAX requests, manage server side state for AJAX clients, and connect AJAX clients to your enterprise resources.

The JavaServer Faces component model is a great fit for defining and using AJAX components.

Won't my server-side framework provide me with AJAX?

You may be benefiting from AJAX already. Many existing Java based frameworks already have some level of AJAX interactions and new frameworks and component libraries are being devel-oped to provide better AJAX support.

I won't list all the Java frameworks that use AJAX here, out of fear of missing someone, but you can find a good list at www.ajaxpatterns.org/Java_Ajax_Frameworks.

If you have not chosen a framework yet it is recommended you consider using JavaServer Faces or a JavaServer Faces based framework.

 JavaServer Faces components can be created and used to abstract many of the details of gen-erating JavaScript, AJAX interactions, and DHTML processing and thus enable simple AJAX used by JSF application developer and as plug-ins in JSF compatible IDE's, such as Sun Java Studio Creator.

1.  Why so JavaScript and Java have similar name? A.  JavaScript is a stripped-down version of JavaB.  JavaScript's syntax is loosely based on Java's C.  They both originated on the island of JavaD.  None of the above

 2.  When a user views a page containing a JavaScript program, which machine actually exe-

cutes the script? A.  The User's machine running a Web browser B.   The Web serverC.  A central machine deep within Netscape's corporate officesD.  None of the above

 3.  ______ JavaScript is also called client-side JavaScript.

A.  MicrosoftB.  NavigatorC.  LiveWireD.  Native

 4.  __________ JavaScript is also called server-side JavaScript.

A.  MicrosoftB.   NavigatorC.  LiveWireD.  Native 

5.  What are variables used for in JavaScript Programs?

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A.  Storing numbers, dates, or other values B.   Varying randomlyC.  Causing high-school algebra flashbacksD.  None of the above 

6.  _____ JavaScript statements embedded in an HTML page can respond to user events such as mouse-clicks, form input, and page navigation.

A.  Client-side B.   Server-sideC.  LocalD.  Native 

7.  What should appear at the very end of your JavaScript? The <script LANGUAGE="JavaScript">tag

A.   The </script>B.    The <script>C.  The END statement D.  None of the above  

8.  Which of the following can't be done with client-side JavaScript? A.  Validating a form B.   Sending a form's contents by email C.  Storing the form's contents to a database file on the server D.  None of the above  

9.  Which of the following are capabilities of functions in JavaScript? A.  Return a value B.   Accept parameters and Return a value C.  Accept parameters D.  None of the above

 10.  Which of the following is not a valid JavaScript variable name?

A.  2names B.   _first_and_last_names C.  FirstAndLastD.  None of the above

 11.  ______ tag is an extension to HTML that can enclose any number of JavaScript statements.

A.  <SCRIPT> B.   <BODY> C.  <HEAD>D.  <TITLE>

 12.  How does JavaScript store dates in a date object?

A.  The number of milliseconds since January 1st, 1970 B.   The number of days since January 1st, 1900 C.  The number of seconds since Netscape's public stock offering. D.  None of the above

 13.  Which of the following attribute can hold the JavaScript version?

A.  LANGUAGE B.   SCRIPTC.  VERSIOND.  None of the above

 14.  What is the correct JavaScript syntax to write "Hello World"?

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A.  System.out.println("Hello World")B.   println ("Hello World")C.  document.write("Hello World") D.  response.write("Hello World")

 15.  Which of the following way can be used to indicate the LANGUAGE attribute?

A.  <LANGUAGE="JavaScriptVersion"> B.   <SCRIPT LANGUAGE="JavaScriptVersion"> C.  <SCRIPT LANGUAGE="JavaScriptVersion">    JavaScript statements…</

SCRIPT>D.  <SCRIPT LANGUAGE="JavaScriptVersion"!>    JavaScript statements…</SCRIPT>

 16.  Inside which HTML element do we put the JavaScript?

A.  <js> B.   <scripting> C.  <script> D.  <javascript>

 17.  What is the correct syntax for referring to an external script called " abc.js"?

A.  <script href=" abc.js">B.   <script name=" abc.js">C.  <script src=" abc.js">D.  None of the above  

18.  Which types of image maps can be used with JavaScript? A.  Server-side image maps B.  Client-side image maps C.  Server-side image maps and Client-side image maps D.  None of the above  

19.  Which of the following navigator object properties is the same in both   Netscape and IE?A.  navigator.appCodeNameB.   navigator.appName C.  navigator.appVersion D.  None of the above

 20.  Which is the correct way to write a JavaScript array?

A.  var txt = new Array(1:"tim",2:"kim",3:"jim") B.   var txt = new Array:1=("tim")2=("kim")3=("jim") C.  var txt = new Array("tim","kim","jim") D.  var txt = new Array="tim","kim","jim"

 21.  What does the <noscript> tag do?

A.  Enclose text to be displayed by non-JavaScript browsers.B.   Prevents scripts on the page from executing. C.  Describes certain low-budget movies. D.  None of the above

 22. If para1 is the DOM object for a paragraph, what is the correct syntax to change the text

within the paragraph? A.  "New Text"? B.  para1.value="New Text"; C.  para1.firstChild.nodeValue= "New Text";D.  para1.nodeValue="New Text";

 23.  JavaScript entities start with _______ and end with _________.

A.  Semicolon, colon B.   Semicolon, Ampersand C.  Ampersand, colon

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D.  Ampersand, semicolon  24.  Which of the following best describes JavaScript?

A.  a low-level programming language. B.   a scripting language precompiled in the browser. C.  a compiled scripting language. D.  an object-oriented scripting language.

 25.  Choose the server-side JavaScript object?

A.  FileUpLoad B.   FunctionC.  FileD.  Date

 26.  Choose the client-side JavaScript object?

A.  Database B.   CursorC.  ClientD.  FileUpLoad

 27.  Which of the following is not considered a JavaScript operator?

A.  new B.  thisC.  deleteD.  typeof 

28.  ______method evaluates a string of JavaScript code in the context of the specified object. A.  EvalB.   ParseIntC.  ParseFloatD.  Efloat

 29.  Which of the following event fires when the form element loses the focus: <button>, <in-

put>, <label>, <select>, <textarea>? A.  onfocus B.  onblur C.  onclickD.  ondblclick

 30.  The syntax of Eval is ________________

A.  [objectName.]eval(numeric) B.  [objectName.]eval(string) C.  [EvalName.]eval(string) D.  [EvalName.]eval(numeric)

 31.  JavaScript is interpreted by _________

A.  ClientB.   ServerC.  ObjectD.  None of the above

 32.  Using _______ statement is how you test for a specific condition.

A.  Select B.  IfC.  SwitchD.  For

 33.  Which of the following is the structure of an if statement?

A.  if (conditional expression is true) thenexecute this codeend if

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B.   if (conditional expression is true)execute this codeend if C.  if (conditional expression is true)   {then execute this code>->}D.  if (conditional expression is true) then {execute this code}

 34.  How to create a Date object in JavaScript?

A.  dateObjectName = new Date([parameters])B.   dateObjectName.new Date([parameters]) C.  dateObjectName := new Date([parameters]) D.  dateObjectName Date([parameters])

 35.  The _______ method of an Array object adds and/or removes elements from an array.

A.  Reverse B.   ShiftC.  SliceD.  Splice

 36.  To set up the window to capture all Click events, we use which of the following statement?

A.  window.captureEvents(Event.CLICK);B.   window.handleEvents (Event.CLICK);C.  window.routeEvents(Event.CLICK );D.  window.raiseEvents(Event.CLICK ); 

37.  Which tag(s) can handle mouse events in Netscape? A.  <IMG> B.  <A> C.  <BR>D.  None of the above

 38.  ____________ is the tainted property of a window object.

A.  Pathname B.   ProtocolC.  Defaultstatus D.  Host

 39.  To enable data tainting, the end user sets the _________ environment variable.

A.  ENABLE_TAINT B.   MS_ENABLE_TAINT C.  NS_ENABLE_TAINT D.  ENABLE_TAINT_NS

 40.  In JavaScript, _________ is an object of the target language data type that encloses an ob-

ject of the source language.A.  a wrapperB.   a linkC.  a cursorD.  a form

   41.  When a JavaScript object is sent to Java, the runtime engine creates a Java wrapper of

type ___________ A.  ScriptObject B.  JSObject C.  JavaObjectD.  Jobject

 42.  _______ class provides an interface for invoking JavaScript methods and examining

JavaScript properties. A.  ScriptObject

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B.  JSObject C.  JavaObjectD.  Jobject

 43.  _________ is a wrapped Java array, accessed from within JavaScript code.

A.  JavaArrayB.   JavaClassC.  JavaObjectD.  JavaPackage

                44. A ________ object is a reference to one of the classes in a Java package, such as netscape.-

javascript .A.  JavaArray B.  JavaClass C.  JavaObjectD.  JavaPackage

 45.  The JavaScript exception is available to the Java code as an instance of __________

A.  netscape.javascript.JSObject B.  netscape.javascript.JSException C.  netscape.plugin.JSException D.  None of the above

 46. To automatically open the console when a JavaScript error occurs which of the following is

added to prefs.js?A.  user_pref(" javascript.console.open_on_error", false);B.   user_pref("javascript.console.open_error ", true);C.  user_pref("javascript.console.open_error ", false);D.   user_pref("javascript.console.open_on_error", true);

 47.  To open a dialog box each time an error occurs, which of the following is added to prefs.js?

A.  user_pref("javascript.classic.error_alerts", true);B.   user_pref("javascript.classic.error_alerts ", false);C.  user_pref("javascript.console.open_on_error ", true);D.  user_pref("javascript.console.open_on_error ", false); 

48.  The syntax of a blur method in a button object is ______________ A.  Blur()B.   Blur(contrast) C.  Blur(value)D.  Blur(depth)

 49.  The syntax of capture events method for document object is ______________

A.  captureEvents() B.   captureEvents(args eventType) C.  captureEvents(eventType) D.  captureEvents(eventVal)

 50.  The syntax of close method for document object is ______________

A.  Close(doc) B.   Close(object) C.  Close(val)D.  Close()