PESIT Bangalore South Campus Hosur road, 1km before Electronic City, Bengaluru -100 Department of Computer Science And Engineering

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1 INTERNAL ASSESSMENT TEST 2 : SOLUTION MANUAL Date : 03/10/17 Max Marks : 50 Subject & Code : Programming the Web / 10CS73 Section : A,B & C Name of Faculty : Ms. Ciji K R, Ms. Kanthimathi S Time : 8:30 to 10:00am What is a DTD? Explain the approach to declare elements, entities and attributes with examples. A Document Type Definition (DTD) is a set of structural rules called declarations, which specify a set of elements that can appear in the document as well as how and where these elements may appear DTDs also provide entity definitions Not all XML documents need a DTD, use of a DTD is related to the use of an external style sheet for XHTML documents A DTD can be embedded in the XML document whose syntax rules it describes, in which case it is called an internal DTD The alternative is to have the DTD stored in a separate file, in which case it is called an external DTD Syntactically, a DTD is a sequence of declarations. Each declaration has the form of a markup declaration: <!keyword > Four possible keywords can be used in a declaration: ELEMENT used to define tags; ATTLIST used to define tag attributes; ENTITY used to define entities; and NOTATION used to define data type notations. Element Declarations: Each element declaration in a DTD specifies the structure of one category of elements The declaration provides the name of the element whose structure is being defined, along with the specification of the structure of that element The form of an element declaration for elements that contain elements is as follows: <!ELEMENT element_name (list of names of child elements)> For ex., consider the following: <!ELEMENT memo (from, to, date, re, body)> 10

2 It is necessary to specify the number of times that a child element may appear This can be done by adding a modifier to the child element specification Child element specification modifiers Modifier Meaning + One or more occurrences * Zero or more occurrences? Zero or one occurrence Consider the following DTD declaration: <!ELEMENT person(parent+, age, spouse?, sibling*)> In this, the person element is specified to have the following children elements: one or more parent elements, one age element, possibly a spouse element, and zero or more sibling elements The form of leaf element declaration is: <!ELEMENT element_name (#PCDATA) Attribute Declarations: An attribute declaration must include the name of the element to which the attribute belongs, the attribute s name, and its type It may also include a default value The general form of an attribute declaration is as follows: <!ATTLIST element-name attribute-name attribute- type [default-value]> If more than one attribute is declared for a given element, the declarations can be combined, as follows: <!ATTLIST element_name attribute_name_1 attribute_type default_value_1 attribute_name_2 attribute_type default_value_2 attribute_name_n attribute_type default_value_n > Possible default values for attributes

3 Value Meaning 2. A value #FIXED value #REQUIRED #IMPLIED Entity Declarations: The quoted value, which is used if none is specified in an element The quoted value, which every element will have And which cannot be changed No default value is given; every instance of the element must specify a value No default value is given Entities can be defined so that they can be referenced anywhere in the content of an XML document, in which case they are called general entities The predefined entities are all general entities Entities can also be defined so that they can be referenced only in DTDs, in which case they are called parameter entities The form of an entity declaration is: <!ENTITY *%+ entity_name entity_value > When the optional % sign is present in an entity declaration, it specifies that the entity is a parameter entity rather than a general entity Ex. If a document has a large no of references to the full name of President Kennedy, an entity can be defined to represent his complete name as: <!ENTITY jfk John Fitzgerald Kennedy > AN XML document that uses a DTD that includes this declaration can specify the complete name with just the reference &jfk; When an entity is longer than a few words, such as the section of technical article, its text is defined outside the DTD. In such cases, the entity is called an external text entity The form of declaration of an external text entity is: <!ENTITY entity_name SYSTEM file_location > The keyword SYSTEM specifies that the definition of the entity is in a different file, which is specified as the string following SYSTEM 2. Explain the JavaScript screen output and keyboard input functions with examples. Standard output for JavaScript embedded in XHTML is the window displaying the page in which the JavaScript is embedded The Window object include two properties, document and window. document.write( The result is,result, </br> ); 10

4 The write method of the Document object write its parameters to the browser window The parameters to write can include any XHTML tags and contents. The window objects: The Window object is the JavaScript model for the browser window It includes 3 methods that create dialogue boxes for 3 specific kinds of user interactions. The alert method opens a dialog box with a message The output of the alert is not XHTML, so use new lines rather than <br/> alert("the sum is:" + sum + "\n"); The confirm methods displays a message provided as a parameter The confirm dialog has two buttons: OK and Cancel If the user presses OK, true is returned by the method If the user presses Cancel, false is returned var qstn =confirm("do you want to continue this download?"); The prompt method: This method displays its string argument in a dialog box The dialog box has an area for the user to enter text The method returns a String with the text entered by the user name = prompt("what is your name?", );

5 3. a Illustrate XSLT processing with the help of a diagram. XSLT is a functional-style programming language XSLT includes functions, parameters, names to which values can be bound, selection constructs, and conditional expressions for multiple selection The syntactic structure of XSLT is XML, so each statement is specified with an element XSLT processors take as input an XML doc and an XSLT doc The XSLT doc is the program to be executed; the XML doc is the input data to the program. Parts of the XML doc are selected, possibly modified, and merged with parts of the XSLT doc to form a new doc, which is sometimes called an XSL doc The XSL doc is also an XML doc, which could be again the input to an XSLT processor The output doc can be stored for future use, or it may be immediately displayed by an application, often by a browser Neither the XSLT doc nor the input XML doc is changed by the XSLT processor The transformation process by XSLT is shown below: 5 If a template matches an element, the element is not processed until the closing tag is found. When a template matches an element, the child elements of that element may or may not be processed

6 b The XSLT model of processing XML data is called the template-driven model, which works well when the data consists of multiple instances of highly regular data collections, as with files of records. XSLT can also deal with irregular and recursive data, using template fragments, in the datadriven model. A single XSLT style sheet can include the mechanisms for both the template-and data-driven models. An XSLT doc consists primarily of one or more templates which use XPath to describe element/attribute patterns in the input XML doc Each template has associated with it a section of XSLT code which is executed when a match to the template is found in the XML doc Each template describes a function which is executed whenever the XSLT processor finds a match to the template s pattern An XSLT processor sequentially examines the XML input doc, searching or parts that match one of the templates in the XSLT doc XML docs consist of nodes, where nodes are elements, attributes, comments, text and processing instructions. 3b. Declare an XML document containing data of 3 employees(emp_id, Emp_Desig, Emp_Age, Emp_phone, Emp_Address)and display this XML data using a CSS with the following styles: Emp_ID in font size -28pts and colour - Red Emp_Name and Emp_desig in font size -18pts and colour Blue Emp_Age,Emp_phone and Emp_Address in font size -15pts and colour Black Employee.xml <?xml version="1.0" encoding="utf-8"?> <?xml-stylesheet type="text/css" href="employee.css"?> <employee>program <emp-info>employee Information</emp-info> <emp1> <emp_id>001</emp_id> <emp_name>sam</emp_name> <emp_desig>programmer</emp_desig> <emp_age>23</emp_age> <emp_ph> </emp_ph> <emp_addr>mandya </emp_addr> </emp1> <emp2> <emp_id>002</emp_id> <emp_name>ram</emp_name> 5

7 <emp_desig>programmer</emp_desig> <emp_age>24</emp_age> <emp_ph> </emp_ph> <emp_addr>mandya </emp_addr> </emp2> <emp3> <emp_id>003</emp_id> <emp_name>tom</emp_name> <emp_desig>teamlead</emp_desig> <emp_age>25</emp_age> <emp_ph> </emp_ph> <emp_addr>bangalore </emp_addr> </emp3> </employee> Employee.css employee-info { display:block; color:blue; font-style:italic; font-size:200%;} employee { display : block; background-color:aqua;font-size:100%; } emp_id { font-size:28pts; colour: Red;} emp_name,emp_desig{font-size:18pts;colour: Blue} emp_age, emp_ph, emp_addr{font-size:15pts;colour: Black} Write an XHTML document containing a JavaScript function to compute the median of an array of numbers using the sort method, with at least two different data sets. 10 //Function median function median(list) { list.sort(function (a,b){return a - b;}); var list_len = list.length; // Use the modulus operator to determine whether the array's length is odd or even // Use Math.floor to truncate numbers // Use Math.round to round numbers if ((list_len % 2) == 1) return list[math.floor(list_len / 2)]; else return Math.round((list[list_len / 2-1] + list[list_len / 2]) / 2); } // end of function median var my_list_1=[8,3,9,1,4,7]; var my_list_2=[10,-2,0,5,3,1,7];

8 var med=median(my_list_1); document.write( Median of [, my_list_1, ] is:, med, <br /> Var med=median(my_list_2); document.write( Median of [, my_list_2, ] is:, med, <br /> Output Median of[8,3,9,1,4,7] is: 6 Median of[10,-2,0,5,3,1,7] is: 3 5 a With respect to XML schemas, explain complex type with examples. Definition of a complex type can specify several categories including element-only elements, which can have elements in their content but no text. All complex types can have attributes. Complex types are defined with the complextype tag. The elements that are the content of the element-only-element must be contained in an ordered group, an unordered group, a choice, or a named group. The sequence element is used to contain an ordered group of elements. <xsd:complextype name= sports_car > <xsd:sequence> <xsd:element name= make type= xsd:string /> <xsd:element name= model type= xsd:string /> <xsd:element name= year type= xsd:decimal /> </xsd:sequence> </xsd:complextype> A complex type whose elements are an unordered group is defined in an all element. Elements and all and sequence groups can include attributes to specify the numbers of occurrences These attributes are minoccurs and maxoccurs The possible values of minoccurs are the non-negative integers, including zero. The possible values of maxoccurs are the non-negative integers plus the value unbounded, which has the obvious meaning. Ex: <xsd:element name = "planes"> <xsd:complextype> <xsd:all> <xsd:element name = "make" type = "xsd:string" minoccurs = "1" maxoccurs = "unbounded" /> </xsd:all> </xsd:complextype>

9 </xsd:element> b Explain XML namespaces with syntax and examples. XML namespace is a collection of element and attribute names used in XML Documents The name of the name space is usually in the form of a Uniform Resource Identifier (URI) A namespace can be declared for an element and its descendants by <element_name xmlns[:prefix]=uri> The square brackets indicate that what is within them is optional. The prefix if included, is the name that must be attached to he names in the declared namespace A prefix is used for 2 reasons First, the URI is too long to be typed on every occurrence of every name from the namespace Second, a URI includes characters that are illegal in XML The element for which a namespace is declared is usually the root of a doc Ex: <html xmlns= > This declares the default namespace, from which names may appear without prefixes As an example of a prefixed namespace declaration, consider the following: <birds xmlns:bd= > Within the birds element, including all its children elements, the names from the namespace must be prefixed with bd as: <bd:lark> If an element has more than one namespace declaration, these are declared as follows: <birds xmlns:bd= xmlns:html= > In the above ex., the standard XHTML namespace is added to the birds element Also, note that in any namespace declaration one of the namespaces can be specified as the default by omitting the prefix The names from the default namespace can be used without a prefix Consider the following example in which 2 namespaces are declared. The first is declared to be the default namespace; the second defines the prefix, cap: <states> xmlns= xmlns:cap= <state> <name> South Dakota </name> <population> </population> <capital> <cap:name> Pierre </cap:name> <cap:population> </cap:population> </capital>

10 </state> <!-- More States --> </states> 6 a Write a note on XML processors. Purposes of XML Processors First, the processor must check the basic syntax of the document for well-formedness Second, the processor must replace all references to entities in an XML doc by their definitions Third, the DTDs and XML schemas can specify that certain values in an XML doc have default values, which must be copied into the XML doc during processing Fourth, when DTD or an XML schema is specified, and the processor includes a validating parser, the structure of the XML doc must be checked to ensure that its structure is legitimate One simple way to check the well-formedness of an XML doc is with a browser that has an XML parser Another way is to run an XML parser directly on the document Two different standards/models for processing SAX (Simple API for XML) approach DOM (Document Object Model) approach SAX Approach SAX was developed by XML DEV, an XML users group The SAX approach to processing is called Event processing The processor scans the document from beginning to end. Every time a syntactic structure of the doc is recognized, the processor signals an event to the application by calling an event handler for the particular structure that was found Syntactic structures include opening tags, attributes, text etc. DOM Approach The natural alternative to the SAX approach is to build a Hierarchical syntactic structure of the doc. Idea-Dynamic documents using java script In the case of XHTML, the browser parses the document and builds the DOM tree In the case of XML, the parser part of the XML processor builds the DOM tree The nodes of the tree are represented as objects that can be accessed and processed or modified by the application When parsing is complete, the complete DOM representation of the doc is in memory and can be accessed in a no of different ways, including tree traversals of various kinds as well as random accesses Advantages of DOM over SAX First, it has an obvious adv if any part of the document must be accessed more than once by the application Second, if the appln must perform any rearrangement of the doc, that can most easily be done if the whole doc is accessible at the same time.

11 Third, access to random parts of the document are possible. Finally, because the parser sees the whole doc, before any processing takes place, this approach avoids any processing of a document that is later found to be invalid(according to a DTD or XML schema) Disadvantages DOM needs large memory since the entire DOM structure is stored in memory Slower than SAX approach Requires syntactic analysis of XML document Most DOM parsers include a SAX parser as a front end b What is an XML schema? Explain defining a schema and a schema instance with an example. XML Schema is an alternative to DTD An XML schema is an XML doc, so it can be parsed with an XML parser A schema is similar to a class definition; an XML doc that conforms to the structure defined in the schema is similar to an object of the schema s class XML docs that conform to a specific schema are considered instances of that schema Schemas themselves are written using a collection of names, or a vocabulary, from a namespace that is, in effect, a schema of schemas The name of this namespace is Every schema has schema as its root element The schema element specifies the namespace for the schema of schemas from which the schema s elements and attributes will be drawn It also specifies a prefix that will be used for the names in the schema The namespace specification appear as: xmlns:xsd= This provides the prefix xsd for the names from the namespace for the schema of schemas A schema defines a namespace in the same sense as a DTD defines a tag set The name of the namespace defined by a schema must be specified with the targetnamespace attribute of the schema element Every top-level (not nested) element that appears in a schema places its name in the target name space The target namespace is specified by assigning a namespace to the target name space attribute as: targetnamespace= If we want the elements and attributes that are not defined directly in the schema element to be included in the target namespace, schema s elementformdefault must be set to qualified as: elementformdefault= qualified The default namespace, which is the source of the unprefixed names in the schema, is given with another xmlns specification.

12 Ex: xmlns= Altogether it looks like: <schema xmlns= targetnamespace= xmlns:plane= elementformdefault= qualified > An instance of a schema must include specifications of the namespace it uses These are given as attribute assignments in the tag for its root element First, an instance doc normally defines its default namespace to be the one defined in its schema The second attribute specification in the root element of an instance doc is for the schemalocation attribute This attribute is used to name the std namespace for instances, which is XMLSchema-instance. This namespace corresponds to the XMLSchema namespace used for schemas. The following attribute assignment specifies the XMLSchema-instance namespace and defines the prefix, xsi for it. xmlns:xsi = Third, the instance document must specify the filename of the schema where the default namespace is defined. This is done with the schemalocation attribute which takes 2 values: the namespace of the schema and the filename of the schema. xsi:schemalocation = http//cs.uccs.edu/planeschema planes.xsd Altogether, the opening root tag of an xml instance of the planes.xsd shema, where the root element name in the instanvce is palnes, could appear as: <planes xmlns= xmlns:xsi= xsi:schemalocation = http//cs.uccs.edu/planeschema planes.xsd > 7 Design an XML document to store information about a student in an engineering college affiliated to VTU. The information must include USN, Name, Name of the College, Branch, Year of Joining, and e- mail id. Make up sample data for 3 students. Create an XSLT style sheet for the student document and use it to display all the student records. <?xml version="1.0" encoding="utf-8"?> <?xml-stylesheet type="text/xsl" href="4b.xsl"?> <student>program <title>program using XSLT stylesheet </title> <stud>

13 <usn>1pe14cs001</usn> <name>abhishek</name> <coll>pesit</coll> <branch>cse</branch> <yoj>2014</yoj> </stud> <stud> <usn>usn:1pe15is001</usn> <name>name:bcd</name> <noc>college:pesit</noc> <branch>branch:ise</branch> <yoj>yoj:2015</yoj> </stud> <stud> <usn>usn:1pe14cs001</usn> <name>name:def</name> <noc>college:pesit</noc> <branch>branch:cse</branch> <yoj>yoj:2014</yoj> </stud> </student> b.xsl <?xml version="1.0" encoding="utf-8"?> <xsl:stylesheet version="1.0" xmlns:xsl=" xmlns=" <xsl:template match="student"> <xsl:for-each select= stud > <span style="font-size:20pt;color:blue"> ===> </span> <span><xsl:value-of select="title" /><br /></span> <span style="font-size:20pt;color:blue">usn:</span> <span><xsl:value-of select="usn" /><br /></span> <span style="font-size:20pt;color:blue">name:</span> <span><xsl:value-of select="name" /><br /></span> <span style="font-size:16pt;color:red">branch :</span> <span><xsl:value-of select="branch" /><br /></span> <span style="font-size:18pt;color:violet">college:</span> <span><xsl:value-of select="coll" /><br /></span>

14 <span style="font-size:18pt;color:yellow">yoj :</span> <span><xsl:value-of select="yoj" /><br /></span> </xsl:for-each> </xsl:template> </xsl:stylesheet> 8 Explain JavaScript arrays with creation and characteristics. Explain array methods with examples. JavaScript Arrays are lists of elements indexed by a numerical value Array index in JavaScript begin at 0 Array elements can be primitive values or references to other objects JavaScript Arrays have dynamic length Arrays object can be created in two distinct ways The usual way to create an array object is with the the new operator and a call to a constructor new Array with one parameter creates an empty array of the specified number of elements new Array with two or more parameters creates an array with the specified parameters as elements var my_list = new Array(100); var my_list = new Array(1, 2, three, four ); The second way to create an array object is with a Literal array value which is a list of values enclosed in brackets: var alist = *1, ii, gamma, 4 +; Elements of an array do not have to be of the same type Characteristics of an Array The length of an array is one more than the highest subscript to which a value has been assigned, plus 1 The length of an array is both read-and write- accessible through the length property The length of an array can be set to whatever you like by assigning the length property as follows: my_list.length=150; Assigning a value to the length property can lengthen, shorten, or not affect the array s length So an array can be made to grow either by adding new elements or by setting its length property to a larger value An array can be made to shrink by setting its length property to a smaller value Only assigned elements of an array actually occupy space The length property of an array is not necessarily the number of defined or even allocated elements Array objects have a collection of useful methods:

15 join reverse sort concat slice The join method converts all the elements of an array to strings and catenates them into a single string If no parameter is provided to join, the values in the new string are separated by commas If a string parameter is provided, it is used as the element separator: var names=new Array* Mary, Murray, Murphy, Max + var name_string=names.join( : ); The value of the name_string is now: Mary : Murray : Murphy : Max The reverse method reverses the order of elements of an Array object through which it is called The sort method coerces the elements of the array to strings, if they are not already strings, and sorts them alphabetically: names.sort(); The values of names is now: * Mary, Max, Murphy, Murray + The concat method catenates its actual parameters to the end of the Array object on which it s called For example, consider the following code: var names=new Array* Mary, Murray, Murphy, Max + var new_names=names.concat( Moo, Meow ); The new_names array now has length 6, with the elements of names, along with Moo and Meow as its fifth and sixth elements The slice method does for arrays what the substr method does for strings It returns the part of the Array object specified by its parameters, which are used as subscripts The returned array has the elements of the array object through which it is called from the 1st parameter upto, but not including the second parameter For example, var list=[2,4,6,8,10]; var list2=list.slice(1,3); The value of list is now[4,6] If slice is given just one parameter, the returned array has all the elements of the object, starting with the specified index: var list=* Bill, Will, Jill, Dill +; var list2=list.slice(2);

16 The value of list2 is [ Jill, Dill ] The push, pop, unshift and shift methods of Array allow the easy implementation of stacks and queues in arrays The pop and push methods remove and add an element to the high end of an array, respectively For example, consider the following: var list=* Bill, Will, Jill, Dill +; var list2=list.pop(); //list2 is Dill list.push( Dill ); //puts Dill back on list The shift and unshift methods remove and add an element to the beginning of an array, respectively * * * * * * *