CoffeeCup

SIMPLE CALCULATOR PROGRAM IN YACC

2015-08-29T02:16:00.000-07:00

LEX PROGRAM

%{
#include <stdio.h>
#include "y.tab.h"
int c;
extern int yylval;
%}
%%
" "       ;
[a-z]     {
            c = yytext[0];
            yylval = c - 'a';
            return(LETTER);
          }
[0-9]     {
            c = yytext[0];
            yylval = c - '0';
            return(DIGIT);
          }
[^a-z0-9\b]    {
                 c = yytext[0];
                 return(c);
               }

YACC PROGRAM

%{
#include <stdio.h>

int regs[26];
int base;

%}

%start list

%token DIGIT LETTER

%left '|'
%left '&'
%left '+' '-'
%left '*' '/' '%'
%left UMINUS /*supplies precedence for unary minus */

%%                   /* beginning of rules section */

list:                       /*empty */
         |
        list stat '\n'
         |
        list error '\n'
         {
           yyerrok;
         }
         ;

stat:    expr
         {
           printf("%d\n",$1);
         }
         |
         LETTER '=' expr
         {
           regs[$1] = $3;
         }

         ;

expr:    '(' expr ')'
         {
           $$ = $2;
         }
         |
         expr '*' expr
         {
           $$ = $1 * $3;
         }
         |
         expr '/' expr
         {
           $$ = $1 / $3;
         }
         |
         expr '%' expr
         {
           $$ = $1 % $3;
         }
         |
         expr '+' expr
         {
           $$ = $1 + $3;
         }
          |

         expr '-' expr
         {
           $$ = $1 - $3;
         }
         |
         expr '&' expr
         {
           $$ = $1 & $3;
         }
         |
         expr '|' expr
         {
           $$ = $1 | $3;
         }
         |

        '-' expr %prec UMINUS
         {
           $$ = -$2;
         }
         |
         LETTER
         {
           $$ = regs[$1];
         }

         |
         number
         ;

number: DIGIT
         {
           $$ = $1;
           base = ($1==0) ? 8 : 10;
         }       |
         number DIGIT
         {
           $$ = base * $1 + $2;
         }
         ;

%%
main()
{
return(yyparse());
}

yyerror(s)
char *s;
{
fprintf(stderr, "%s\n",s);
}

yywrap()
{
return(1);
}

HOW TO COMPILE & EXECUTE CALCULATOR PROGRAM IN YACC

SAVE THE PROGRAM
LEX PROGRAM: nameofprogram.l
YACC PROGRAM: nameofprogram.y

DO THE FOLLOWING,

lex nameofprogram.l
yacc nameofprogram.y
cc lex.yy.c y.tab.c
./a.out

Enter the Expression
12+12
24

Thank you.

Internal Server Error

2014-02-22T23:44:00.000-08:00

Internal server Error

The server encountered an internal error (Internal Server Error) that prevented

it from fulfilling this request.

Problem Description:

Invalid class file format.

Such error occurred when executing servlet program.

Solution :

Check whether you are installed java on your machine.

If it is installed then please check jre file of java is corrupted or no.

Such problem only occur when Jre on your machine was corrupted.

Just uninstall java and install fresh copy of Java.

Again execute your program and see output will appear.

Thank you.

HOW TO COMPILE AND RUN SERVLET PROGRAM

2014-01-10T10:09:00.000-08:00

1) SAVE SERVLET PROGRAM IN BELOW DIRECTORY OF YOUR MACHINE

C:\Program Files\Apache Tomcat 4.0\webapps\examples\WEB-INF\classes

2) SET ENVIRONMENT VARIABLE

JUST GO TO MY COMPUTER

RIGHT CLICK ON IT .

GO TO PROPERTIES

3) GO TO ADVANCED TAB

CLICK ON ENVIRONMENT VARIABLE TAB

4) SET THE FOLLOWING PATH

i) CLASSPATH

Variable name: CLASSPATH

Variable value: C:\Program Files\Apache Tomcat 4.0\common\lib\servlet.jar; C:\Program Files\Java\jdk1.5.0_06;

PATH ABRIVIATION

CLASSPATH

Path up to Apache tomcat\common\lib\servlet.jar file,then semicolon followed by jdk directory.

ii) PATH

Variable name: PATH

Variable value: C:\Program Files\Java\jdk1.5.0_06\bin;

PATH ABRIVIATION

PATH

Path up to jdk\bin directory .

5) AFTER THAT COPY servlet.jar FILE FROM

C:\Program Files\Apache Tomcat 4.0\common\lib

AND PASTE IN FOLLOWING DIRECTORY

C:\Program Files\Java\jre1.5.0_06\lib\ext

OPEN COMMAND PROMPT & COMPILE SOURCE PROGRAM

6) Start tomcat server,

7) Go to Internet Explorer, Type following URL

http://localhost:8080/examples/servlet/Nameof yourServlet

8) Thank you

Hello World Program of Servlet

2014-01-10T09:40:00.000-08:00

What is Servlet?

Java Servlet is programs that run on a Web or Application server and act as a middle layer between a requests coming from a Web browser or other HTTP client and databases or applications on the HTTP server.

Types of Servlet

Generic Servlet

The Generic Servlet is an abstract class that is extended by HttpServlet to provide HTTP protocol-specific methods.

The Generic Servlet does not include protocol-specific methods for handling request parameters, cookies, sessions and setting response headers.

Generic Servlet is not specific to any protocol.

HTTP Servlet

An abstract class that simplifies writing HTTP servlet. It extends the GenericServlet base class and provides an framework for handling the HTTP protocol.

The HttpServlet subclass passes generic service method requests to the relevant doGet () or doPost () method.

HttpServlet only supports HTTP and HTTPS protocol.

HelloWorld Program

import java.io.*;

import java.text.*;

import java.util.*;

import javax.servlet.*;

import javax.servlet.http.*;

public class HelloWorldExample extends HttpServlet {

public void doGet(HttpServletRequest request,HttpServletResponse response) throws IOException, ServletException

{

response.setContentType("text/html");

PrintWriter out = response.getWriter();

out.println("<html>");

out.println("<head>");

out.println("</head>");

out.println("<body>");

out.println("<h1>HelloWorld</h1>");

out.println("</body>");

out.println("</html>");

}

How To compile and Execute/run servlet program

Servlet Packages

Servlet can be created using the javax.servlet and javax.servlet.http packages, which are a standard part of the Java's enterprise edition, an expanded version of the Java class library that supports large-scale development projects.

HelloWorld Program of Servlet

1. import package

import java.io.*;

This package is for input /output operation.

import javax.servlet.*;

import javax.servlet.http.*;

This two package mainly responsible for Servlets implementation.

Servlet life cycle

A servlet life cycle can be defined as the entire process from its creation till the destruction. The following are the paths followed by a servlet.
The servlet is initialized by calling the init () method.
The servlet calls service() method to process a client's request. The servlet is terminated by calling the destroy() method. Finally, servlet is garbage collected by the garbage collector of the JVM.

What is the difference between difference between doGet() and doPost()?

doGet () and doPost() are HTTP requests handled by servlet classes.

In doGet (), the parameters are appended to the URL and sent along with header information. This does not happen in case of doPost(). In doPost(), the parameters are sent separately. Since most of the web servers support only a limited amount of information to be attached to the headers, the size of this header should not exceed 1024 bytes. doPost() does not have this constraint. Usually programmers find it difficult to choose between doGet() and doPost(). doGet() shall be used when small amount of data and insensitive data like a query has to be sent as a request. doPost() shall be used when comparatively large amount of sensitive data has to be sent. Examples are sending data after filling up a form or sending login id and password.

XML DATABASE

2013-12-06T21:04:00.005-08:00

What is an XML Database?

An eXtensible Markup Language (XML) database is a software system that permits data storage in XML format. XML is a meta-markup language used to manage data which employs user customizable tags to organize information. The flexibility of the language, which allows the creation of custom data structures and organizational systems, has led to its widespread use to exchange data in multiple forms. XML databases are often used in applications such as informational portals, document exchanges, and product catalogs.

It is generally considered more efficient in terms of data conversion costs to use an XML database due to the widespread use of this language in data transportation. There are two major categories of these databases: XML-enabled databases and Native XML databases (NXD). Each type of XML database is used to store different types of data.

An XML-enabled database directs data into a traditional relational database in an XML format. The data is translated for storage, and returned to its initial format upon output. This type of database is used to store data-centric documents which include highly structured information, such as patient records, and only use XML for data transfer.

Native XML databases store XML documents as a whole, instead of separating out the data within them, and are designed to store semi-structured information, such as marketing brochures or health data. XML documents that contain semi-structured data are referred to as document-centric. A native XML database does not conform to a certain physical storage model, being able to use relational, hierarchical, or object-oriented structures as well as custom storage formats. It manages documents by grouping them into logical collections, and can set up and manage multiple collections simultaneously. This type of database permits the user to store any type of XML document, regardless of structure, within the same collection. Queries can be constructed across the whole collection, generally making data organization and manipulation more flexible.

An XML database uses a special programming language designed specifically to extract and manipulate XML documents, known as XQuery. The purpose of XQuery is to allow the construction of flexible queries that can extract and manipulate information from XML documents, as well as other sources that can be translated into XML. Some applications in which XQuery can be used include searching text documents on the Web for relevant data and compiling the results, extracting data from databases to be used in application integration, and generating reports on the data contained in an XML database.

XML and Databases

In the document-centric model of XML where XML is typically used as a means to creating semi-structured documents with irregular content that are meant for human consumption. An example of document-centric usage of XML is XHTML which is the XML based successor to HTML.

Sample XHTML document

<head>

<title>Sample Web Page</title>

</head>

<body>

<h1>My Sample Web Page</h1>

<p> All XHTML documents must be well-formed and valid. </p>

</body>

</html>

The other primary usage of XML is in a data-centric model. In a data-centric model, XML is used as storage or interchange format for data that is structured, appears in a regular order and is most likely to be machine processed instead of read by a human. In a data-centric model, the fact that the data is stored or transferred as XML is typically incidental since it could be stored or transferred in a number of other formats which may or may not be better suited for the task depending on the data and how it is used. An example of a data-centric usage of XML is SOAP. SOAP is an XML based protocol used for exchanging information in a decentralized, distributed environment. A SOAP message consists of three parts: an envelope that defines a framework for describing what is in a message and how to process it, a set of encoding rules for expressing instances of application-defined data types, and a convention for representing remote procedure calls and responses.

Sample SOAP message taken from w3c soap recommendation

<SOAP-ENV:Envelope xmlns:SOAP-ENV=http://schemas.xmlsoap.org/soap/envelope/

SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">

<SOAP-ENV:Body>

<m:GetLastTradePrice xmlns:m="Some-URI">

</m:GetLastTradePrice>

</SOAP-ENV:Body>

</SOAP-ENV:Envelope>

In both models where XML is used, it is sometimes necessary to store the XML in some sort of repository or database that allows for more sophisticated storage and retrieval of the data especially if the XML is to be accessed by multiple users. Below is a description of storage options based on what model of XML usage is required.

Data-centric model:

In a data-centric model where data is stored in a relational database or similar repository; one may want to extract data from a database as XML, store XML into a database or both. For situations where one only needs to extract XML from the database one may use a middleware application or component that retrieves data from the database and returns it as XML. Middleware components that transform relational data to XML and back vary widely in the functionality they provide and how they provide it. For instance, Microsoft's ADO.NET provides XML integration to such a degree that results from queries on XML documents or SQL databases can be accessed identically via the same API.

The alternative to using middleware components to retrieve or store XML in a database is to use an XML-enabled database that understands how to convert relational data to XML and back. Currently, the Big 3 relational database products all support retrieving and storing XML in one form or another. IBM's DB2 uses the DB2 XML Extender. The DB2 extender gives one the option to store an entire XML document and its DTD as a user-defined column or to slice the document into multiple tables and columns. XML documents can then be queried with syntax that is compliant with W3C XPath recommendation. Updating of XML data is also possible using stored procedures.

Document-centric model

Content management systems are typically the tool of choice when considering storing, updating and retrieving various XML documents in a shared repository. A content management system typically consists of a repository that stores a variety of XML documents, an editor and an engine that provides one or more of the following features:

o version, revision and access control

o ability to reuse documents in different formats

o collaboration

o web publishing facilities

o support for a variety of text editors (e.g. Microsoft Word, Adobe Framemaker, etc)

o indexing and search capabilities

Content management systems have been primarily of benefit for workflow management in corporate environments where information sharing is vital and as a way to manage the creation of web content in a modular fashion allowing web developers and content creators to perform their tasks with less interdependence than exists in a traditional web authoring environment.

Hybrid model

In situations where both document-centric and data-centric models of XML usage will occur, the best data storage choice is usually a native XML database. The most coherent definition so far is one that was reached by consensus amongst members of the XML: DB mailing list which defines a native XML database as a database that has an XML document as its fundamental unit of (logical) storage and defines a (logical) model for an XML document, as opposed to the data in that document, and stores and retrieves documents according to that model. At a minimum, the model must include elements, attributes, PCDATA, and document order. Tamino is a native XML database management system developed by Software AG. Tamino is a relatively mature application, currently at version 2.3.1, that provides the means to store & retrieve XML documents, store & retrieve relational data, as well as interface with external applications and data sources. Schemas in Tamino are DTD-based and are used primarily as a way to describe how the XML data should be indexed. When storing XML documents in Tamino; one can specify a pre-existing DTD which is then converted to a Tamino schema, store a well-formed XML document without a schema which means that default indexing ensues or a schema can be created from scratch for the XML document being stored. A secondary usage of schemas is for specifying the data types in XML documents.

XML Schema Definition with example

2013-12-04T22:14:00.001-08:00

XSD (XML Schema Definition)

A Recommendation of the World Wide Web Consortium, specifies how to formally describe the elements in an Extensible Markup Language document. This description can be used to verify that each item of content in a document adheres to the description of the element in which the content is to be placed.

The XML Schema Definition is a reference library that provides an API for use with any code that examines, creates or modifies W3C XML Schema (standalone or as part of other artifacts, such as XForms or WSDL documents).

XSD is a library that provides an API for manipulating the components of an XML Schema as described by the W3C XML Schema specifications, as well as an API for manipulating the DOM-accessible representation of XML Schema as a series of XML documents, and for keeping these representations in agreement as schemas are modified.

XSD has several advantages over earlier XML schema languages, such as document type definition (DTD) or Simple Object XML (SOX). For example, it's more direct: XSD, in contrast to the earlier languages, is written in XML, which means that it doesn't require intermediary processing by a parser. Other benefits include self-documentation, automatic schema creation, and the ability to be queried through XML Transformations (XSLT). Despite the advantages of XSD, it has some detractors who claim, for example, that the language is unnecessarily complex.

e.g.

Hello.xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<city>Kadegaon</city>

<country>India</country>

</shipto>

<item>

</item>

<item>

</item>

</shiporder>

Hello.xsd

<?xml version="1.0"?>

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:element name="shiporder">

<xs:complexType>

<xs:sequence>

<xs:element name="orderperson" type="xs:string"/>

<xs:element name="shipto">

<xs:complexType>

<xs:sequence>

<xs:element name="name" type="xs:string"/>

<xs:element name="addr" type="xs:string"/>

<xs:element name="city" type="xs:string"/>

<xs:element name="country" type="xs:string"/>

</xs:sequence>

</xs:complexType>

</xs:element>

<xs:element name="item" maxOccurs="unbounded">

<xs:complexType>

<xs:sequence>

<xs:element name="title" type="xs:string"/>

<xs:element name="note" type="xs:string"/>

<xs:element name="quantity" type="xs:string"/>

<xs:element name="price" type="xs:string"/>

</xs:sequence>

</xs:complexType>

</xs:element>

XML Schema

2013-12-04T21:50:00.002-08:00

What is XML Schema?

XML Schema is an XML-based language used to create XML-based languages and data models. An XML schema defines element and attribute names for a class of XML documents. The schema also specifies the structure that those documents must adhere to and the type of content that each element can hold. XML documents that attempt to adhere to an XML schema are said to be instances of that schema. If they correctly adhere to the schema, then they are valid instances. This is not the same as being well formed. A well-formed XML document follows all the syntax rules of XML, but it does necessarily adhere to any particular schema. So, an XML document can be well formed without being valid, but it cannot be valid unless it is well formed.

The Power of XML Schema:

You may already have some experience with DTDs. DTDs are similar to XML schemas in that they are used to create classes of XML documents. DTDs were around long before the advent of XML. They were originally created to define languages based on SGML, the parent of XML. Although DTDs are still common, XML Schema is a much more powerful language.

Limitations of DTD:

1. DTDs do not have built-in data types.

2. DTDs do not support user-derived data types.

3. DTDs allow only limited control over cardinality (the number of occurrences of an element within its parent).

4. DTDs do not support Namespaces or any simple way of reusing or importing other schemas.

Form of an XML Schema Definition:

An XML Schema is an XML document.

First item: xml declaration

<?xml version="1.0"?>

XML comments and processing instructions are allowed.

Root element: schema with a namespace declaration.

<xs:schema

xmlns:xs="http://www.w3.org/2001/XMLSchema">

</xs:schema>

Possible namespace prefixes: xs, xsd, or none.

Element Specification

Elements are declared using an element named xs:element with an attribute that gives the name of the element being defined. The type of the content of the new element can be specified by another attribute or by the content of the xs:element definition. Element declarations can be one of two sorts.

Simple Type

Content of these elements can be text only.

Examples

<xs:element name="item" type="xs:string"/>

<xs:element name="price" type="xs:decimal"/>

The values xs:string and xs:decimal are two of the 44 simple types predefined in the XML Schema language.

Complex Type

Element content can contain other elements or the element can have attributes (or both).

Example

<xs:element name="location">

<xs:complexType>

<xs:sequence>

<xs:element name="city" type="xs:string"/>

<xs:element name="state" type="xs:string"/>

</xs:sequence>

</xs:complexType>

</xs:element>

The element xs:sequence is one of several ways to combine elements in the content.

Corresponding DTD: <! ELEMENT location (city, state)>

Other xs:element Attributes

An xs:element element may also have attributes that specify the number of occurrences of the element at this position in the sequence.

minOccurs="0" // default = 1

maxOccurs="5" // default = maximum(1, minOccurs)

maxOccurs="unbounded"

Mixed Content

Mixed content refers to the situation where an element has both text and elements in its content. Because of the sub-elements, the element being defined must be a complex type. To allow mixed content in an element definition, simply add an attribute mixed to the xs:complexType starting tag that asserts:

mixed="true"

This attribute has a default value of "false".

Simple Types

XML Schema Definitions provide a rich set of predefined primitive types along with a mechanism to customize these types to create an accurate specification of XML documents. The predefined types can be classified into several groups. Numeric, Date and time, XML types, String, Boolean, URIs, and Binary data.

Unions

A simple type can be defined as the (disjoint) union of two existing simple types. The element xs:union has an attribute memberTypes whose value is a space-separated list of simple types that have already been defined.

Example

Suppose we want to store exam scores, but in some instances, the grade may not be available.

1. Define a type representing a missing score.

<xs:simpleType name="noScoreType">

<xs:restriction base="xs:string">

<xs:enumeration value="none"/>

</xs:restriction>

</xs:simpleType>

2. Define a union type of integer scores and missing scores.

<xs:simpleType name="scoreOrNoType">

<xs:union memberTypes ="xs:integer noScoreType"/>

</xs:simpleType>

3. Define a list of the union type.

<xs:simpleType name="scoreOrNoList">

<xs:list itemType ="scoreOrNoType "/>

</xs:simpleType>

4. Define a type whose values can be a list of scores (or

none) or can be a date on which we can expect the grades

to be made available.

<xs:simpleType name="scoresOrDateType">

<xs:union memberTypes ="xs:date scoreOrNoList"/>

</xs:simpleType>

How to convert XML into HTML by using XSLT

2013-12-04T02:36:00.000-08:00

XSLT

eXtensible Stylsheet Language for Transformation specifies rules for conversion i.e. template or template rules. There are two types of template rules for transformation: Matching and selection templates, and Branching elements.

How to convert XML into HTML

e.g. Hello.xml

<?xml version="1.0" encoding="UTF-8"?>

<?xml-stylesheet type="text/xsl" href="nrs.xsl"?>

<day1>

</day1>

<day1>

<location>Kolhapur</location>

</day1>

</weather1>

e.g. Hello.xsl

<?xml version="1.0" encoding="UTF-8"?>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">

<xsl:template match="weather1">

<html>

<body>

<tr>

<th>

<font size="10" color="red">Location</font>

</th>

<th>

</th>

<th>

</th>

</tr>

<xsl:for-each select="//day1">

<tr>

<td>

<xsl:value-of select="location"/>

</td>

<td>

<xsl:value-of select="date"/>

</td>

<td>

<xsl:value-of select="temp"/>

</td>

</tr>

</xsl:for-each>

</table>

</body>

</html>

</xsl:template>

</xsl:stylesheet>

Save both these program in one directory.

check well form of each one .

Run Hello.xml and Watch the output of xml file into html.

eXtensible stylesheet Language [XSL]

2013-12-03T22:46:00.000-08:00

What is XSL?

XSL stands for eXtensible Stylesheet Language which is much like XML. XSL is a language for expressing stylesheets. It consist of XSLT, is an application for specifying rules by which one XML document is transformed into another XML document; Xpath, Expression language used by XSLT to locate elements and attributes in an XML document. It also tests Boolean conditions, perform numerical calculations; XSL-FO (Formatting Objects), which specifies formatting properties for rendering the document to some other format.

Advantages:

Easy display formatted XML data in browser

Easier to modify when XML data format changes than to modify DOM and SAX parsing code

Can be used with database queries that return XML

Disadvantages:

Memory exhaustive, performance hit.

Difficult to implement complex business rules

XSLT:

eXetensible Stylsheet Language for Transformation specifies rules for conversion i.e. template or template rules. There are two types of template rules for transformation: Matching and selection templates, and Branching elements.

Matching and selection templates

xsl:template

xsl:apply-templates

xsl:value-of

Branching elements

xsl:for-each

xsl:if

xsl:choose

Matching and selection templates

xsl:template :

xsl:template match=“XPath” :

Defines a template rule for producing output. It is applied only to nodes that match the pattern.

It is invoked by using <xsl:apply-templates/>

<xsl:template match="/">

<xsl:apply-templates/>

</body></html>

</xsl:template>

<xsl:template match=“name">

Your name is <xsl:value-of select=“first”/>

</xsl:template>

xsl:value-of select:

xsl:value-of select=“expression” :

It evaluates the expression as a string and outputs the result. It is applied only to the first match. The “.” selects the text value of the current node.

e.g.

xsl:for-each select:

xsl:for-each select=“expression”:

It processes each node selected by the XPath expression. It is applied only to the first match. The “.” selects the text value of the current node

e.g.

<class>

</class>

xsl:if test:

xsl:if test=“expression”:

It evaluates the expression and if true applies the template.

<xsl:template match=“class">

<xsl:if select=“position() = first()">

</xsl:if>

</xsl:template>

xsl:choose :

It selects any number of alternatives. It is used instead of if-else, or switch statement used in other programming languages.

<xsl:choose>

<xsl:when test=“not(text())">

Missing value!

</xsl:when>

<xsl:otherwise>

<xsl:value-of select=“.”/>

</xsl:otherwise>

</xsl:choose>

Simple Way to do DOM parser program

2013-12-03T00:08:00.000-08:00

DOM: Document Object Model

A DOM Document is a collection of nodes, or pieces of information, organized in a hierarchy. This hierarchy allows a developer to navigate around the tree looking for specific information.

Analyzing the structure normally requires the entire document to be loaded and the hierarchy to be built before any work is done. Because it is based on a hierarchy of information, the DOM is said to be tree-based, or object-based.

DOM create in build memory tree like structure, whenever it starts

Parsing, after completing parsing of entire file that tree throws to application program to handle each and every events occurred in it.

Parsing a file into a document:

It is three-step process. To work with the information in an XML file, the file must be parsed to create a Document object. The Document object is an interface, so it can't be instantiated directly; generally, the application uses a factory instead. The exact process varies from implementation to implementation, but the ideas are the same.

In the example Java environment, parsing the file is a three-step process:

1. Create the DocumentBuilderFactory. This object creates the DocumentBuilder.

2. Create the DocumentBuilder. The DocumentBuilder does the actual parsing to create the Document object.

3. Parse the file to create the Document object.

Now you can start building the application

First, the Java code imports the necessary classes, and then it creates the OrderProcessor application. The Document object can be used later; the application defines it outside the try-catch block. Within the try-catch block, the application creates the DocumentBuilderFactory, which it then uses to create the DocumentBuilder. Finally, the DocumentBuilder parses the file to create the Document.

Once the document is parsed and a Document is created, an application can step through the structure to review, find, or display information. This navigation is the basis for many operations that will be performed on a Document. Stepping through the document begins with the root element. A well-formed document has only one root element, also known as the DocumentElement. First the application retrieves this element.

DOM Example:

Input XML File for parsing

<?xml version="1.0" encoding="UTF-8"?>

<day1>

</day1>

</weather>

DOM Program for XML File parsing

import java.io.File;

import javax.xml.parsers.*;

import org.w3c.dom.*;

public class Dom

{

public static void main(String args[])

{

try

{

File f=new File("weather.xml");

DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();

DocumentBuilder db=dbf.newDocumentBuilder();

Document doc=db.parse(f);

System.out.println("RootNode="+doc.getDocumentElement().getNodeName());

}

catch(Exception e)

{ e.printStackTrace();

}

How to compile and run Dom parser program.

Save these two programs in same directory Jdk/bin

Compile all programs and run it

Your Output will display.

SAX Parser : One type for XML Parser

2013-12-02T00:01:00.001-08:00

XML Parser

An XML parser is a piece of code that reads an XML document and analyzes its structure. There are different kinds of XML parsers- SAX, DOM, and JAXP.

SAX: The Simple API for XML

Overview

SAX is a push API. You create a SAX parser, and the parser tells you (it pushes events to you) when it finds things in the XML document. Specifically, here's how SAX addresses the concerns mentioned in the previous panel:

SAX doesn't build an in-memory tree of an XML document. A SAX parser sends you events as it finds things in an XML document. It's up to you to decide how (or if) you want to store that data.

A SAX parser doesn't create any objects. You have the option of creating objects if you want, but that's your decision, not the parsers.

SAX starts sending you events immediately. You don't have to wait for the parser to finish reading the document.

SAX events

The SAX API defines a number of events. Some commonly used SAX events are given below.In a SAX-based XML application, you'll spend most of your time looking at five basic events.

startDocument()

This event tells you that the parser has found the start of the document. This event doesn't pass you any information, it simply lets you know that the parser is about to begin scanning the document.

endDocument ()

This event tells you that the parser has found the end of the document.

startElement(...)

This event tells you that the parser has found a start tag. This event tells you the name of the element, the names and values of all of the element's attributes, and gives you some namespace information as well.

characters (...)

This event tells you that the parser has found some text. You get a character array, along with an offset into the array and a length variable; together, those three variables give you the text the parser found.

endElement(...)

This event tells you that the parser has found an end tag. This event tells you the name of the element, as well as the associated namespace information.

startElement(), characters(), and endElement() are the most important events. All of the events here are part of the ContentHandler interface; other SAX interfaces are defined to handle errors as well as entities and other rarely-used things.

SAX Parser Program

//Simple Sax Parser Program

//SAX.java

import java.io.*;

import javax.xml.parsers.*;

import org.xml.sax.*;

public class SAX

{

public static void main(String[] args)

{

try

{

File f=new File("www.xml");

SAXParserFactory spf=SAXParserFactory.newInstance();

SAXParser sp=spf.newSAXParser();

mySAXHandler sh=new mySAXHandler();

sp.parse(f,sh);

}

catch(Exception e)

{

e.printStackTrace();

}

class mySAXHandler extends HandlerBase

{

public void startDocument()

{

System.out.println("start document");

}

public void endDocument()

{

System.out.println("end document");

}

public void startElement(String name,AttributeList al)

{

System.out.println("start "+name+" Element");

}

public void endElement(String name)

{

System.out.println("end "+name+" Element");

}

//Input XML file which is supplied to Sax parser program for parsing

//www.xml

<?xml version="1.0" encoding="UTF-8"?>

<day1>

<location>SanFransico</location>

</day1>

</weather>

How to compile & Run this program

Ø Save both the program in Jdk/bin directory

Ø Compile SAX.java program in usual java programming way

Ø javac SAX.java

Ø run the same program

Ø java SAX.java

You will get the Output.Your valuable comments are waiting .thank you...

XML & DTD

2013-11-24T22:25:00.000-08:00

Document Type Definition

The purpose of a DTD (Document Type Definition) is to define the legal building blocks of an XML document. A DTD defines the document structure with a list of legal elements and attributes. A DTD can be declared inline inside an XML document, or as an external reference.

Internal DTD Declaration:

If the DTD is declared inside the XML file, it should be wrapped in a DOCTYPE definition with the following syntax:

<! DOCTYPE root-element [element-declarations]>

XML document with an internal DTD:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE weather[

<!ELEMENT weather (day1)>

<!ELEMENT day1 (location,date,temp)>

<!ELEMENT location (#PCDATA)>

<!ELEMENT date (#PCDATA)>

<!ELEMENT temp (#PCDATA)>

<!ENTITY GM "Good Morning">

<!ENTITY GN "Good Night">

<day1 >

<location>&GM; Sanfransico </location>

</day1>

</weather>

The DTD above is interpreted like this:

!DOCTYPE note defines that the root element of this document is note

!ELEMENT note defines that the note element contains four elements: "to, from, heading, body"

!ELEMENT to defines the to element to be of type "#PCDATA"

!ELEMENT from defines the from element to be of type "#PCDATA"

!ELEMENT heading defines the heading element to be of type "#PCDATA"

!ELEMENT body defines the body element to be of type "#PCDATA"

External DTD Declaration

If the DTD is declared in an external file, it should be wrapped in a DOCTYPE definition with the syntax:

<! DOCTYPE root-element SYSTEM "filename">

whether.xml

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE weather SYSTEM "weather.dtd">

<day1>

</day1>

</weather>

weather.dtd

<!ELEMENT weather (day1)>

<!ELEMENT day1 (location,date,temp)>

<!ELEMENT location (#PCDATA)>

<!ELEMENT date (#PCDATA)>

<!ELEMENT temp (#PCDATA)>

<!ENTITY GM "Good Morning">

<!ENTITY GN "Good Night">

Why to Use a DTD?

With a DTD, each of your XML files can carry a description of its own format. With a DTD, independent groups of people can agree to use a standard DTD for interchanging data. Your application can use a standard DTD to verify that the data you receive from the outside world is valid. You can also use a DTD to verify your own data.

The Building Blocks of XML Documents

All XML documents are made up by the following building blocks:

Elements, Attributes, Entities, PCDATA, and CDATA .

Elements

Elements are the main building blocks of both XML and HTML documents.

Attributes

Attributes provide extra information about elements. Attributes are always placed inside the opening tag of an element. Attributes always come in name/value pairs.

Entities .Some characters have a special meaning in XML, like the less than sign (<) that defines the start of an XML tag.

PCDATA

PCDATA means parsed character data.

CDATA

CDATA means character data.

XML & RELATED TECHNIQUES

2013-11-24T22:04:00.000-08:00

What is XML?

XML stands for Extensible Markup Language which is much like HTML. XML was designed to carry data, not to display data.

XML tags are not predefined. You must define your own tags. XML is designed to be self-descriptive.

Features of XML:

1. With XML You Invent Your Own Tags

2. XML Separates Data from HTML

3. XML Simplifies Data Sharing

4. XML Simplifies Data Transport

XML Syntax Rules:

All XML Elements Must Have a Closing Tag.

XML Tags are Case Sensitive.

XML Elements Must be Properly Nested.

XML Documents Must Have a Root Element.

XML Attribute Values Must be quoted.

Comments in XML:

The syntax for writing comments in XML is similar to that of HTML.

<! -- This is a comment -->

What is an XML Element?

An XML element is everything from (including) the element's start tag to (including) the element's end tag. An element can contain other elements, simple text or a mixture of both. Elements can also have attributes.

E.g. XML Example

<?xml version="1.0" encoding="UTF-8"?>

<day1>

<location>Sanfransico</location>

</day1>

</weather>

In the example above, <weather> and <day1> have element contents, because they contain other elements. <location> has text content because it contains text.

XML Naming Rules

XML elements must follow these naming rules:

Names can contain letters, numbers, and other characters

Names cannot start with a number or punctuation character

Names cannot start with the letters xml (or XML, or Xml, etc)

Names cannot contain spaces

Any name can be used, no words are reserved.

Well Formed XML Documents:

A "Well Formed" XML document has a correct XML syntax.

XML Namespaces

XML Namespaces provide a method to avoid element name conflicts

Name Conflicts

In XML, element names are defined by the developer. This often results in a conflict when trying to mix XML documents from different XML applications.

XML Namespaces - The xmlns Attribute

When using prefixes in XML, a so-called namespace for the prefix must be defined. The namespace is defined by the xmlns attribute in the start tag of an element. The namespace declaration has the following syntax. xmlns: prefix="URI".

Uniform Resource Identifier (URI)

A Uniform Resource Identifier (URI) is a string of characters which identifies an Internet Resource. The most common URI is the Uniform Resource Locator (URL) which identifies an Internet domain address. Another, not so common type of URI is the Universal Resource Name (URN).

JDBC Driver and Database Connection

2013-11-21T02:22:00.003-08:00

To Store form data to database using JDBC Driver

Many applications require storing form data into database. In this post we will study JDBC driver to implement database .

The Common Gateway Interface (CGI) has and continues to be the most commonly used method for creating dynamic and responsive web pages. The main problem with CGI is that each new client request results in a new instance of the CGI executable being formed by the HTTP daemon. Servlets is the Java answer to the CGI problem. Servlets are Java classes, loaded and kept resident by the HTTP daemon. When the servlet is loaded, database connections can be established and held between client requests.

What is JDBC?

Java Database Connectivity or JDBC for short is set of Java API's that enables the developers to create platform and database independent applications in java.

What are JDBC Drivers?

JDBC Drivers are set of classes that enable the Java application to communicate with databases. Java.sql that ships with JDK contains various classes for using relational databases. But these classes do not provide any implementation, only the behaviors are defined. The actual implementations are done in third-party drivers. Third party vendors implement the java.sql.Driver interface in their database driver.

JDBC Drivers Types

Sun has defined four JDBC driver types. These are:

Type 1: JDBC-ODBC Bridge Driver

The first type of JDBC driver is JDBC-ODBC Bridge which provides JDBC access to any ODBC compliant databases through ODBC drivers. Sun's JDBC-ODBC bridge is example of type 1 driver.

Type 2: Native -API Partly - Java Driver

Type 2 drivers are developed using native code libraries, which were originally designed for accessing the database through C/C++. Here a thin code of Java wrap around the native code and converts JDBC commands to DBMS-specific native calls.

Type 3: JDBC-Net Pure Java Driver

Type 3 drivers are three-tier solutions. This type of driver communicates to a middleware component which in turn connects to database and provide database connectivity.

Type 4: Native-Protocol Pure Java Driver

Type 4 drivers are entirely written in Java that communicates directly with vendor's database through socket connection. Here no translation or middleware layer, are required which improves performance tremendously.

There are seven standard steps in querying databases:

1. Load the JDBC driver.

2. Define the connection URL.

3. Establish the connection.

4. Create a statement object.

5. Execute a query or update.

6. Process the results.

7. Close the connection.

Here are some details of the process.

Load the Driver

The driver is the piece of software that knows how to talk to the actual database server.

Use Class.forName (), this method takes a string representing a fully qualified class name (i.e., one that includes package names) and loads the corresponding class. This call could throw a ClassNotFound- Exception, so should be inside a try/catch block.

e.g.

try

{
          Class.forName("connect.microsoft.MicrosoftDriver");
          Class.forName("oracle.jdbc.driver.OracleDriver");
          Class.forName("com.sybase.jdbc.SybDriver");

}

catch (ClassNotFoundException cnfe)

{

System.err.println("Error loading driver: " + cnfe)

}

Define the Connection URL

Once you have loaded the JDBC driver, you need to specify the location of the database server. URLs referring to databases use the JDBC: protocol and have the server host, port, and database name (or reference) embedded within the URL. The exact format will be defined in the documentation that comes with the particular driver.

Establish the Connection

To make the actual network connection, pass the URL, the database username, and the password to the getConnection () method of the Driver- Manager class,

String username = "data";

String password = "xyz";

Connection connection = DriverManager.getConnection(oracleURL, username, password);

Create a Statement

A Statement object is used to send queries and commands to the database and is created from the Connection as follows:

Statement statement = connection.createStatement();

Execute a Query

Once you have a Statement object, you can use it to send SQL queries by using the executeQuery method, which returns an object of type Result-Set.

e.g.

String query = "SELECT col1, col2, col3 FROM Table_1";

ResultSet resultSet = statement.executeQuery(query);

To modify the database, use executeUpdate instead of executeQuery, and supply a string that uses UPDATE, INSERT, or DELETE.

Process the Results

The simplest way to handle the results is to process them one row at a time, using the ResultSet’s next method to move through the table a row at a time. Within a row, ResultSet provides various getXxx methods that take a column index or column name as an argument and return the result as a variety of different Java types. For instance, use getInt if the value should be an integer, getString for a String, and so on for most other data types. If you just want to display the results, you can use getString regardless of the actual column type.

while(resultSet.next())

{
           System.out.println(results.getString(1) + " " +
           results.getString(2) + " " +
           results.getString(3));

}

Close the Connection

To close the connection explicitly, you would do:

connection.close();

Configuration of Apache Tomcat Server

2013-11-21T01:58:00.000-08:00

Setting up Tomcat port

Tomcat use 8080 port instead of 80 port. User can easily change default port from tomcat.

Open c:/tomcat/config/server.xml folder in tomcat installed and open server.xml file.

<! -- Define a non-SSL HTTP/1.1 Connector on port 8080 --> <Connector port="8080" maxHttpHeaderSize="8192" maxThreads="150" minSpareThreads="25" maxSpareThreads="75" enableLookups="false" redirectPort="8443" acceptCount="100" connectionTimeout="20000" disableUploadTimeout="true" /> <! -- Note: To disable connection timeouts, set connectionTimeout value to 0 -->

In connector port change 8080 to 80, now save this save and shutdown.bat tomcat and startup.bat tomcat. This time user needs not to write 8080 port in http://localhost/

Servlet invoker

Servlet container of tomcat engine doesn’t start automatically. WEB-INF deployment descriptor needs to tell servlet engine, where your servlet and mapping of servlet. This is can be done without any setting through servlet invoker. We just need to uncommented the code in web.xml in config folder. Servlet invoker automatically load servlet in context and map it.

Open c:/tomcat/config/web.xml and edit this code as shown.

First uncommented invoker then servlet mapping

  

<servlet> <servlet-name>invoker</servlet-name> <servlet-class> org.apache.catalina.servlets.InvokerServlet </servlet-class> <init-param> <param-name>debug</param-name> <param-value>0</param-value> </init-param> <load-on-startup>2</load-on-startup> </servlet>

Also uncommented the servlet mapping

 <servlet-mapping> <servlet-name>invoker</servlet-name> <url-pattern>/servlet/*</url-pattern> </servlet-mapping>

If you are using tomcat 6, need to define privileges for context. In tomcat 5.5.x version no need to define privileges for context. Tomcat 5.5.x takes automatically.

Privileges setting can be done in tomcat/conf/context.xml file. Add this line

Deployment of jsp or servlet in Tomcat

All jsp and html page should be kept in C:\tomcat\webapps and create your own folder or keep jsp file under default directory ROOT. We would like to create new folder in webapps as home and keep all files in this folder. In home folder create WEB-INF folder and inside this also create two folder named as classes and lib and keep web.xml in WEB-INF. In classes’ folder, all servlets and JavaBeans should keep, Classes folder generally contains class file and java file and when servlet engine starts, all java and class file loaded in tomcat through bootstrap.jar which is in bin folder. Create a first servlet example.

Deployment of Servlet

Servlet deployment needs to map in deployment descriptor, if you have not enabled servlet invoker. Descriptor give us more feature of deploying servlet with user defined URL context path.

All servlet needs to compile manually and copy to WEB-INF/classes folder. Descriptor file is web.xml which keeps all information of servlet and taglib’s. Suppose we are deploying TestServlet servlet at default package. WEB-INF/classes/TestServlet.class; Make a file

WEB-INF/web.xml

web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="2.5"

xmlns="http://java.sun.com/xml/ns/javaee"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/javaee

http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

<servlet>

<servlet-name>TestServlet</servlet-name>

<servlet-class>TestServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>TestServlet</servlet-name>

<url-pattern>/servlet/TestServlet</url-pattern>

</servlet-mapping>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>

Installation of Tomcat on Windows

2013-11-20T00:50:00.002-08:00

What is Tomcat ?

Tomcat is java based web server, support jsp, servlet, and java application, but does not work as application server.

Tomcat need java environment to execute jsp and servlet or java class files. This needs to be JVM installed on server or machine, before running Tomcat. Java, JDK, JRE, JVM is available freely from sun, and other third party.

Installation of JDK Java

Download JDK or JRE from http://java.sun.com/javase/downloads/index.jsp.

Sun provides different executable file for Windows and Linux operating system version. Sun provide JDK for Linux in .bin or tar.gz format, and for Windows.exe format. After downloading file from sun, install JDK, simple double click or through command prompt. Default installation directory for java in Windows is Program file à Java, and Linux /opt. Tomcat 5.5.17 version requires at least java1.5 version. When jdk is installed in default location, need to configure the environment variable.

Environment Variable Setting

Environment variable is next to set java home in system environment. This will help to know others application where java is is installed and where java files have to compile. JAVA_HOME variable name needs to set in environment variable as variable name and variable value as the java home directory c:\ jdk1.5.0.

Step to do this setting, go to my computer icon and right click and go to properties

My computer->right click->properties-> Advance tab->environment variables ->

User variables –> New

Click on new button and new pop up will open. In variable value, enter your java path where java is installed in system.

Tomcat Installation

Tomcat installation is of two types.

Apache provides self-installer for tomcat installation. This tomcat is in executable binary file. Download, and install, self-installer do all work automatically.

Second is source code extractor. This tomcat installation is also easy as self-installer. Before tomcat installation, check all jvm, java, and environment path set properly.

Apache tomcat is freely available from Apache Jakarta site:

http://archive.apache.org/dist/tomcat/tomcat-5/

According to per requirement, tomcat is downloaded in form of binaries or source code. We are using zipped pack for windows installation. Download zipped binaries code latest one from this site. Unzip this code and c:\ drive and anywhere desired directory. After unzipped directory system will like that

This is means that tomcat is installed properly and ready to run web server. Open bin directory and double click on start up.bat file. Start-up.bat will open in dos command prompt.

After starting tomcat, check tomcat in web browser by typing local host: 8080 in address bar http://localhost:8080/

How To Compile and Execute Servlet Program

2013-11-19T23:10:00.003-08:00

Servlet

Java Servlet is kind of java program that process and answer client request.It is also java programming language class that used to extend capabilities of server.

Here we are looking for how to compile servlet program and execute it

Pr-requisite: Here we used

jdk1.5.0_05,
Tomcat 4.1,
Servlet program Name: FirstServlet.java
Program saved into below directory:

C:\Program Files\Apache Group\Tomcat 4.1\webapps\examples\WEB-INF\classes\

Follow Instruction below

Right click on your My Computer icon of desktop.

Go to -> Advanced Tab. -> Environmental variables

Click on that you will find all the system variables lies over there.

In User Variables section you can create environmental variables. Now click on new

1) Variable name: class path

value :<path till lib of installed java>e.g.(C:\Program Files\Java\jdk1.5.0\lib);.;<path till lib of tomcat> e.g.(C:\Program Files\Apache Software Foundation\Tomcat 6.0\lib);<path till jsp- api.jar>;<path till servlet-api.jar>e.g(C:\Program Files\Apache Software Foundation\Tomcat 6.0\lib\servlet-api.jar;C:\Program Files\Apache Software Foundation\Tomcat 6.0\lib\jsp- api.jar);.;

CLASSPATH
C:\Program Files\Java\jdk1.5.0_05\lib;C:\Program Files\Apache Group\Tomcat 4.1\common\lib;C:\Program Files\Apache Group\Tomcat 4.1\common\lib\servlet.jar;

2) Variable name: path

Value: <path till bin of installed java>;<path till bin of tomcat> click ok to create this variable.

PATH
C:\Program Files\Java\jdk1.5.0_05\bin;C:\Program Files\Apache Group\Tomcat 4.1\bin;

3) Variable name: CATALINA_HOME

Value :< path till tomcat base> e.g.(C:\Program Files\Apache Software Foundation\Tomcat 6.0)

CATALINA_HOME
C:\Program Files\Apache Group\Tomcat 4.1;C:\Program Files\Java\jdk1.5.0_05;

4) Variable name: JAVA_HOME

Value : <path till java base> e.g.(C:\Program Files\Java\jdk1.5.0)

JAVA_HOME
C:\Program Files\Java\jdk1.5.0_05

Then after,

Open command prompt,

Cd\
Cd C:\Program Files\Apache Group\Tomcat 4.1\webapps\examples\WEB-INF\classes\
Compile your Servlet program,
javac FirstServlet.java
Start tomcat server,
Internet Explorer,.
http://localhost:8080/examples/servlet/FirstServlet

Your Output will display

Tomcat 1.5 or higher version

Compile the program and place .class file into

C:\Program Files\Apache Software Foundation\Tomcat 5.5\webapps\servlets- examples\WEB-INF\classes this Directory.

Make Change into web.xml file,

<servlet>
<servlet-name>Nameof Program</servlet-name> <servlet-class> Nameof Program </servlet-class> </servlet> <servlet-mapping>
<servlet-name> Nameof Program </servlet-name> <url-pattern>/servlet/ Nameof Program </url-pattern> </servlet-mapping> http://localhost:8080/servlets-examples/servlet/ Nameof Program

Your Output will display....Thank You.

Database Connectivity program in java using MS access Database

2013-09-27T02:36:00.000-07:00

What is Database ?

Database is a collection of information stored and retrieve from same. Database is one of the storage of data so that it can be available to retrieve whenever need.

Types of Database?

1.Relational Database

2.Object Oriented Database

3.Hierarchical Database

4.Network Database

Database Connectivity program in java using MS access Database

import java.io.*;

import java.sql.*;

class DatabaseProgram

{

public static void main(String args[])

{

try

{

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

Connection con=DriverManager.getConnection("jdbc:odbc:Data");

Statement stmt=con.createStatement();

System.out.println("Connection established");

con.close();

}

catch(Exception e)

{

e.printStackTrace();

}

How to execute Database connectivity program in java by using Ms access.

1.Copy this program in your Notepad

2.save this program in JDK/bin directory as DatabaseProgram.java

3.Create MS access Database as mentioned in post

"How to create Database by using MS Access"

4.Go to Control panel ->Administrative tool ->Create DSN ->Give the DSN Name as: Data

5.Click on Select button to select database file .finally press OK button

6.Go to command prompt

7.Compile source program by using command

javac DatabaseProgram.java

8.Run this program

java DatabaseProgram

9.Output will look like:

Connection established

How to create Database by using MS Access

2013-09-25T05:00:00.001-07:00

1 Install Microsoft office (Ignore if already installed)

office.microsoft.com/‎
We are here using MS office 2007

2.      Open Microsoft Office Access



3.      Create new database file and click on create button OK.

4.      Open table in design view.

5.      Specify column name and there data type.

6.      Save the table and add the data.

7.      Your Database is Created.

i if you have any problem or have any question then leave your comment.

Easy steps for Applet program

2012-08-27T00:27:00.000-07:00

Applet

Applet is an application running on web browser. it is designed to be transmitted over the internet and running always on client machine.

Web Architecture

Applet are small application that are accessed on a Internet server, transported over the Internet, automatically installed & run as part of web document.

Hierarchy of Applet

Applet Life Cycle

init() :this is for initialization as like constructor ,it is automatically called by system itself.

start() : this methods automatically calls when java calls init method

stop() : this method automatically calls when user moves off the page on which the applet sits.

destroy() : Java is guaranted to call this method when the browser shuts down normally.

paint(Graphics g) : The paint( ) method is called each time your applet’s output must be redrawn.

Simple Applet Program

Follow the steps for applet program

1. Write the Simple program

import java.awt.*;

import java.applet.*;

class MyApplet extends Applet

{

public void paint (Graphics g)

{

g.drawString ("Hello World", 25, 50);

}

2. Save this program as MyApplet.java,

3. Compile Applet program by using command javac MyApplet.java

4. After that do the HTML code as like below

<html>

<head>This is Applet Program</head>

<body>

</applet>

</body>

</html>

5. Save this html code as Applet.html.and open it into web browser.See output.

Restriction of Applet

Applet can never run any local executable program.
Applet can’t communicate with an internet site other than the one that served the web page that included the applet.
Applet can’t read/write files on user’s file system.
All windows popped by an applet carry a warning message.
Applet can never find any info about the local computer.

If any problem persist use comment line to share your problem.

Simple way to Create Package in Java

2012-08-12T09:23:00.000-07:00

Package in Java

Package is collection of classes and interfaces.
this is the way of grouping classes and interfaces into the single directory.

How to use package ?

In Java, lots of predefined packages are implemented.like java.util , java.io ,java.awt etc.Use an import keyword when we have to use these packages functionality.

How to use import Keyword ? When to use import keyword ?

these are the two basic question ,use import keyword as shown below:

import java.NameOf Package;

for example ,lets consider you have to import util package in your class,then your import statement is as look like below statement.

import java.util.*;

here:
import : Keyword in java
java.util : Name of Package
* : All content present in respective package.

Use the import keyword whenever the class in the particular package has to be used.

Application of Package :

Avoid Naming complexity
Hide the implementation details of classes.
It allows us to grouping classes and interfaces into the same directory.

How to Create My Own Package

follow the next steps

Use the keyword package at the beginnning of your class.
Create Directory of that package Name
Compile the classes and copy the .class file into package directory.
Run your program by using following command

java NameOf Package.ClassName

Write a program to Create a User defined package

Listen friend ,here you are creating your own package.you have to follow next procedure for the same purpose.

//Simple Program

package myPackage;
class SampleOne
{
public void run()
{
System.out.println("This is run method");
}

}

//Save this program as SampleOne.java and create new java program for next program

package myPackage;
class SampleTwo extends SampleOne
{
public void running()
{
  System.out.println("This is running method");
}
public static void main(String[] args)
{
  SampleTwo st=new SampleTwo();
  st.run();
  st.running();
  System.out.println("Hello World!");
}
}

//Save this program as SampleTwo.java and follow next procedure

How to Compile and Run package program

Got to cmd.
In cmd,Go to path upto Java\jdk\bin

Comile the first program :

javac SampleOne.java

copy SampleOne.class file from bin directory to package directory called myPackage
then compile Second program

javac SampleTwo.java

copy SampleTwo.class file from bin directory to package directory called myPackage
Run the program

java myPackage.SampleTwo

Output looks like as below

here is your package will create with name myPackage.

If you have any doubt or wants some more program then keep use comment line ,I will reply you as soon as possible.

Program to Implement Vector class

2012-08-11T02:45:00.001-07:00

What is Vector class ?
Vector class is predefined class in java.This class is present inside the java.util package.
Vector is similar like Array but having some difference between them.

Vector is having many predefined method as array dont have it.
Vector is synchronized.
Vector is very useful when if you dont know the size of array earlier or you have to change the size over the lifetime of your program.

Vector class and their method

//Write a program to add some element into the Vector and remove any element,Display the result.
//Example of Vector class.

import java.util.*;
class VectorDemo
{
public static void main(String[] args)
{
  Vector v=new Vector();
  int a=args.length;
  for(int i=0;i<a;i++)
  {
   v.addElement(args[i]);
  }
  int size=v.size();
  System.out.println("Initial Size of Vector:"+size);
  String b[]=new String[size];
  v.copyInto(b);
  for(int i=0;i<size;i++)
  {
   System.out.println("Elements of Vector:"+i+":"+b[i]);
  }
  v.removeElementAt(2);
  int s=v.size();
  v.copyInto(b);
  System.out.println("After Removing Element,Size of Vector:"+s);
  for(int i=0;i<s;i++)
  {
   System.out.println("Elements of Vector:"+i+":"+b[i]);
  }

}
}

Save this program as      VectorDemo.java

Compile it
                                     javac VectorDemo.java

Run it
                                     java VectorDemo 4 5 8 9

Output

If you have any trouble or wants some more program then paste your problem statement on comment line.I will definately give you responce as early as possible.

Pascal Triangle in Java

2012-08-09T23:22:00.002-07:00

What is Pascal Triangle ?

Pascal triangle is triangular array of the binomial coefficent in a triangle.It is named from the name of french mathematician Blaise Pascal.
Figure shows the structure of pascal triangle having result up to six th rows.

Pascal Triangle

//Write a Program to implement Pascal Triangle by using Java?

import java.util.*;
class Pascal
{
public static void main(String args[])
{
    Scanner sc=new Scanner(System.in);
   System.out.print("Enter the limit: ");
   int x=sc.nextInt();
   int arr[][]=new int [x][x];

for(int i=0;i<x;i++)
{

for(int j=0;j<x;j++)
{

arr[i][0]=1;

}

for(int i=1;i<x;i++)
{

for(int j=1;j<x;j++)
{

arr[i][j]=arr[i-1][j-1]+arr[i-1][j];
}

}

for(int i=1;i<x;i++)
{

for(int j=1;j<x;j++)
{

if(i==j)
arr[i][j]=1;

}

   for(int i=0;i<x;i++)
   {
     for(int k=x;k>=i;k--)
      {

System.out.print(" ");

       }
      for(int j=0;j<=i;j++)
       {

System.out.print(arr[i][j]+" ");

}
System.out.println();

}

}
}

Save this program as Pascal.java

Compile Java program by using command javac Pascal.java

Run this program by using command java Pascal

See the Output :

If you want some more pattern code then just mail me nihalcse@gmail.com

Some more Reference:

Pascal's triangle ,|| Blaise Pascal ,|| triangular array ,|| binomial coefficients

Pattern Programming

2012-07-31T04:18:00.001-07:00

Pattern Programming:
Pattern programming is a series of program which may contain curtain pattern having an output into the form like shapes of triangle,diamond,kites,square,rectangle and many more.

Below is some of the example of Pattern :

//Pattern Programming : Program of Kites from Java

class Pattern
{
    public static void main(String args[])
    {
        int no=4;
        for(int i=0;i<no;i++)
        {
            for(int k=no;k>i;k--)
            {
                System.out.print(" ");
            }
            for(int j=0;j<=i;j++)
            {
                System.out.print("* ");
            }
            System.out.print("\n");
        }
        for(int i=no;i>=0;i--)
        {
            for(int k=no;k>i;k--)
            {
                System.out.print(" ");
            }
            for(int j=0;j<=i;j++)
            {
                System.out.print("* ");
            }
            System.out.print("\n");
        }
        for(int i=1;i<no;i++)
        {
            for(int k=no;k>i;k--)
            {
                System.out.print(" ");
            }
            for(int j=0;j<=i;j++)
            {
                System.out.print("* ");
            }
            System.out.print("\n");
        }
    }
}

Save this program as Pattern.java

Compile Java program by using command javac Pattern.java

Run this program by using command java Pattern.java

See the Output :

If you want some more pattern output then just mail me @ nihalcse@gmail.com

Armstrong Number

2012-07-27T03:06:00.001-07:00

What is Armstrong Number ?
An Armstrong number is an integer such that the sum of the cubes of its digits is equal to the number itself.

for example:
Lets consider the following number:
                                                         153
                                                         370
                                                         371
                                                         407

153=1^3+5^3+3^3
      =153

370=3^3+7^3+0^3
      =370

371=3^3+7^3+1^3
      =371

407=4^3+0^3+7^3
      =407

//Program to check Whether given number is armstrong number or not by using Java.

class ArmstrongNumber
{
public static void main(String args[])
{
     int a,b,c=0,n=153;
     a=n;
     while(n>0)
     {
        b=n%10;
        c=c+(b*b*b);
        n=n/10;
     }
    if(a==c)
    {
     System.out.println("This number is Armstrong number:"+c);
     }
    else
     {
       System.out.println("This number is not Armstrong number:"+c);
     }
}
}

Save this program as      ArmstrongNumber.java

Compile it
                                     javac ArmstrongNumber.java

Run it
                                     java ArmstrongNumber

Output

                                   This number is Armstrong number:153

If you have any trouble or wants some more program then just reach @ nihalcse@gmail.com

CoffeeCup

SIMPLE CALCULATOR PROGRAM IN YACC

Internal Server Error

HOW TO COMPILE AND RUN SERVLET PROGRAM

Hello World Program of Servlet

XML DATABASE

XML Schema Definition with example

XML Schema

How to convert XML into HTML by using XSLT

eXtensible stylesheet Language [XSL]

Simple Way to do DOM parser program

SAX Parser : One type for XML Parser

XML & DTD

XML & RELATED TECHNIQUES

JDBC Driver and Database Connection

Configuration of Apache Tomcat Server

Installation of Tomcat on Windows

How To Compile and Execute Servlet Program

Database Connectivity program in java using MS access Database

Database Connectivity program in java using MS access Database

How to execute Database connectivity program in java by using Ms access.

"How to create Database by using MS Access"

4.Go to Control panel ->Administrative tool ->Create DSN ->Give the DSN Name as: Data

5.Click on Select button to select database file .finally press OK button

6.Go to command prompt

7.Compile source program by using command

javac DatabaseProgram.java

8.Run this program

java DatabaseProgram

9.Output will look like:

Connection established

How to create Database by using MS Access

Easy steps for Applet program

Applet

Web Architecture

Hierarchy of Applet

Applet Life Cycle

Simple Applet Program

Follow the steps for applet program

Restriction of Applet

Simple way to Create Package in Java

Package in Java

How to use package ?

How to use import Keyword ? When to use import keyword ?

import java.NameOf Package;

import java.util.*;

Use the import keyword whenever the class in the particular package has to be used.

Application of Package :

How to Create My Own Package

follow the next steps

java NameOf Package.ClassName

Write a program to Create a User defined package

//Simple Program

//Save this program as SampleOne.java and create new java program for next program

//Save this program as SampleTwo.java and follow next procedure

How to Compile and Run package program

javac SampleOne.java

javac SampleTwo.java

java myPackage.SampleTwo

Program to Implement Vector class

Pascal Triangle in Java

What is Pascal Triangle ?

//Write a Program to implement Pascal Triangle by using Java?﻿

If you want some more pattern code then just mail me nihalcse@gmail.com

Some more Reference:

Pattern Programming

Armstrong Number

//Write a Program to implement Pascal Triangle by using Java?