Forms of JavaBeans

In the previous article, we have already learn about basic concept of java bean, today i am talking about java beans forms.
Java Beans can appear in two forms:

1. Visual
2. Non visual.

Visual is more common, as the majority of Java Beans are extensions of Swing or AWT components. Some Beans may be simple GUI elements such as a specialized button or slider. Others may be sophisticated visual software components such as a diagram component offering different ways to present the bounded data. They all have in common that they can be customized at design time in a builder tool.

Java Beans can also be non visual yet still be customizable using a builder-tool. They do not have to be derived from a specific class or interface, it is recommended that they implement the Serializable interface. In respect of the source code there is no real difference noticeable between a Java Bean and a “normal” Java class. Basically what differs the source code of a “normal” class from a Java Bean is that the latter adheres to the Java Beans API specification in terms of how it is developed. Only the strict adherence to this specification ensures that builder tools can assist a developer to work with Java Beans. For many solutions you can either develop a conventional Java class where you have to write your own code for setting its properties or you can build a Java Bean which allows you To set the properties through the builder tool. Eventually both methods result in code just that in the latter case the builder tool creates the code automatically in the background according to your selection.

Introduction of JavaBeans

A Java Bean is a software component that has been designed to be reusable in a variety of different environments. There is no restriction on the capability of a Bean. It may perform a simple function, such as checking spelling of a document, or a complex function, such as forecasting the performance of a stock portfolio. A Bean may be visible to an end user. One example of this is a button on a graphical user interface. A Mean may also be invisible to a user. Software to decode a stream of multimedia information in real time is an example of this type of building block. A Bean may be designed to work autonomously on a user’s workstation or to work in cooperation with a set of other distributed components. Software to generate a pie chart from a set of data points is an example of a Bean that can execute locally.

A Bean that provides real-time price information from a stock or commodities exchange would need to work in cooperation with other distributed software to obtain its data.

Java Beans components, or beans, are reusable software components that follow simple naming and design conventions so they present a standard interface to other beans, programs, and tools. In the next video tutorial i will learn about forms of java beans.

File types, Text and Binary in C

As discussed earlier the C language provides flexibility for the programmers to write file handling programs to store and process data. Such data files contain the data effectively in two formats. So, on the basis of the format structure of the files are of two types, Text File and Binary File.

Text File

In a text file a stream of characters are stored sequentially without any formatting. So, it is very simple to handle but direct access is not possible because any value or character is not stored after fixed number of bytes. Even though the numbers are stored in the form of characters only and the record length is not fixed if the records are stored. Again the records are also stored in the character format of the individual fields.

Similarly, since text files only process characters, generally they can only read or write data one character at a time. But the flexible C Language provides file handling functions to read and write formatted data and lines of text in a text file. But these functions again basically process data one character at a time. The normal functions used to handle the text file are getc(),fgetc(),fgets(), fputs(), putc(),fputc(),fscanf() and fprintf(). These functions transfer the character/s to and from the text file.

Depending on the requirements of the OS (Operating System), newline character may be converted to or from carriage-return/linefeed combination depending on the data is being written to, or read from, the file. Other character conversions may also occur to satisfy the storage requirements of the OS. These translations occur transparently and they occur while processing a text file.

Binary File

A binary file is not much different to a text file. It is also a collection of bytes. But the transfer of data is purely in the form of bytes as stored in main memory. Any number of bytes can be transferred at a time, in binary file. But the length of the bytes transferred is fixed. So, the binary files contain the data in fixed length record format. That is the reason they are more effective than text files. One important advantage of fixed length is that of accessing the record directly. The direct access is possible only in case of the binary files. It is basically because when a record is written to a binary file form the memory, the complete memory block is written. The number of bytes transferred is fixed. In the same manner when the data is read from the binary file the number of bytes is transferred to the memory at the provided address. The file handling functions provided to handle the binary files are fread() and fwrite(). This fixed length transfer is advantageous for direct access but the size of the file increases. So, in comparison to text files the binary files are advantageous in direct access at the cost of the size. Thus a selection of type of file is decided keeping the accessibility of data in mind.

A binary file is also referred to as a character stream but differ in the following ways:

• No special processing of the data occurs and each byte of data is transferred unprocessed to or from the disk.

• C Language places no constraints on the file, and it may be read from, or written to, in any manner.

Binary files can be either processed sequentially or randomly. The processing of a binary file using random access techniques involves moving the file pointer position to an appropriate place in the file before reading or writing data. This indicates a second characteristic of binary files; the binary files are generally processed using read and write operations simultaneously. For example, for the creation and processing a database file the best choice is a binary file. A record update operation will involve locating the appropriate record, reading the record into memory, modifying it in some way, and finally writing the record back to disk at its appropriate location in the file. These kinds of operations are common to many binary files, but are rarely found in applications that process text files.

The type of the file to be processed is decided at the time of opening a file. At the time of opening a file the mode of operation is mentioned indicating text file or binary file. The function fopen() provides the capability of opening a file. By default the file is opened in text mode. If the binary file is to be processed then it is explicitly defined as “b” along with the other required mode character ‘r’, ‘w’ or ‘a’.

When the file is opened the mode of operation is specified. It indicates the types of files “text” and "binary". The text file is advantageous in terms of size and the binary file in terms of random or direct access.

Online Movie ticket booking System project in ASP.NET

Introduction 

Through this software, You can reserve your movie hall ticket online. Basically this system categories in two parts, the first part related to visitor who want to book ticket and second part is related to admin who handle all the privileges like user account, payment account etc. When visitors visit the home page of this site then they will see the first interface of the project that is movie name with full description and book now button. When visitors click on book now button then they will go to the next page that is login page. If the visitors are authenticated person then no need to register again, simply login into the account. After login they will see the seat no , visitor can reserve multiple seat at a time.

Module of the project

• Viewer module
• Admin module

Software requirement to run this software

Visual Studio 2013 and windows 8

How to run this project

1. First to open the project in visual studio 2013 

2. Click to green color of triangle button, also you can use ctrl+f5.

Project Module

1. Visitor, who want to reserve seat

2. Admin

Snap Shot of the project

Ticket Booking snap

Ticket Cancel Snap

How to Download the project

Mail me : narenkumar851@gmail.com

File Pointer in C

In order to use files it is mandatory to learn the file Input / Output operations. Learning of these is nothing but to understand the functions to write data into a file, to read data from a file, etc. For at any of such operations the file must be opened. The file opening operation is done through a pointer variable called as file pointer. So, file pointer is nothing but a variable which is declared and then I to any required physical file. All the I/O operations are done to physical file through the logical file.

A File Pointer is a special type of pointer variable of the type FILE that is used to store the address of a physical file.

FILE I/O is almost identical to the console and terminal I/O operations. The pnntf() function is used to display the data on the screen. And in file handling we use fprintf() to write the data into the file. We use scanf() function to read the data from the keyboard. And in file handling we use fscanf() to read the data from the file. This is called file manipulation.

The major difference between manipulation of file and terminal I/O is that the terminal I/O is standard no need to specify anything but it is necessary to specify files to be used in the programs where file I/O are performed. It is possible have many files on the disk. If you wish to use a file or files in the programs, then you must specify which file or files you wish to use. Specification of the file that is to be used is referred as opening a file.
At the time of opening the file it is also compulsory to specify the type of operation to be performed i.e. Read from the file, Write to the file, or both. This specification is done through the file opening mode. When different files are used in the program, it is required to specify a particular file for reading or writing. It can be done using a variable called a FILE pointer.

Every file you open has its own FILE pointer variable. When you wish to write to a fiie you specify the file by using its file pointer variable. The file pointer declared using FILE data type is called as logical file. The data is not stored permanently on the secondary storage with this name. It is stored with other file name which is called as physical file name. The logical file is linked with this physical file name. The read/write operations are done on logical file in the program which is indirectly transferred from or to the physical file. The linking of logical file with physical file is done through fopen() function. The FILE pointer variables can be declared as follows:

FILE *fP1, *fp2, *fp3;

The variables fpl, fp2, fp3 are the pointer variables of the type FILE or simply file pointers. They can store the address of any physical file.

Any name can be used as file pointer but must be a valid variable or identifier name of C language. The rules of standard data type identifiers apply to these variables also. The declared FILE Pointer variable may hold address of any physical file but only one at a time. So, at a given point of time logically a logical file points to one and only one physical file. The read / write operactions performed on the file pointer indirectly directed to physical file. At the time of opening file the file pointed by file pointer variable is mentioned along with the type of operation. The opened file is closed when the operation is finished or whenever a new file is to be attached. We will discuss file opening and closing in more details in the next article.

File Structure in C

The file meant for a C programmer is nothing but a data file. Using C programs the data in the form of character or characters is stored permanently on the secondary storage device. In file handling such programs are designed that store data in file and read back data from the file. It means the file replaces the input/output devices for I/O operations. Rather than displaying the data on the output device monitor, it can be written to the file or the data can be read from the file instead of the input device like keyboard. Contents of a file describe the structure of a file.

The way how the contents of a file are being managed or decided is called as file Structure. It may be character, fields, records or block of records.

Each and every data stored in a file can be treated simply as character. So, the character is simplest unit of transfer. In its simplest structure a file can contain a character. More number of characters can be stored in file to make it meaningful. If the transfer rate is simply a character then there is lots of overhead. In order to overcome this overhead the characters can be grouped into many numbers of characters. A file with ‘character’ structure looks as follows:

POEM.TXT
Twinkle twinkle little star!
How I wonder what you are?
Up above the world so high!
Like a diamond in the sky.


In this case of the file ‘POEM.TXT’ each time a single character is written in the file. The file is simply a collection of cnaracters. So, the structure of the file is 'character'. [A text file]
The grouped characters can be transferred to or from the file. In such case a ‘field' can be treated as unit of transfer. The field here is nothing but a variable of any standard data type. So, the file can now contain these fields in its structure. The length of the field varies according to the contents in it. It is not fixed. So, the random access is not possible. The field values must be separated by a marker indicating end of the value. The file creator must take care in such cases.

A file with ‘field’ structure looks as follows:

STUDENT.DAT
101 jacob 102 jacob2
103 bill  104  bill2
105 jacob3 106  bill3


In this case of the file ‘STUDENT.DAT’ each time the data from variables is transferred. Two variables like 'rollno' and 'name’ are used in this case. The file is a collection of data in the form of characters only. But the structure of the file is ‘field’.

The fields that logically explain the characteristics of a person or a thing can be grouped in the form of 'records’ and  these records can be stored in the file. The file is now a collection of records.So, the unit of transfer in this case will be a record. A whole record can be transferred at a time to or from the file. So, in this case the structure of a file can have records in it. Generally here the file contains fixed length records. Number of bytes transferred is equal to the length of record. So, a record containing many fields is transferred, individual fields.

A file with ‘record’ structure looks as follows:

EMP.DAT

101   A    25400
10    B    3240
13    C    12500
104   D    5400


In this case of the file ‘EMP.DAT’ each time the data from a complete record is transferred. For the sake of understanding each record is written in new line. The record structure consists of three fields (like ‘empno’, ‘empname’ and ‘salary’) are used in this case. The file is a collection of data in the form of records only. But the length of the record is fixed. So, there is chance of wastage of storage space. But random access or direct access is the great utilization of fixed length ‘record structure’.

 Further the records can be grouped into ‘blocks’. A block may contain ‘n’ number of records. In such case the data transfer rate is in terms of ‘block’. A block can be transferred at a time. So, the structure of file is ‘block’ of records.

 In order to support such files the definition of the control structure for streams defined in C which as “FILE structure” is defined as follows:

typedef struct {

int level;     /* Full or empty level of buffer*/
unsigned flags;    /* File status flags */
char fd;           /* File descriptor (handler) */
unsigned char hold; /* Used to indicate no buffer */
int bsize;           /* Buffer size */
unsigned char *buffer;  /* Data transfer buffer */
unsigned char *curp;  /* Current active pointer */
unsigned istemp;  /* Temporary file indicator*/
short token;      /* Used for validity checking*/

} FILE;

FILE is the structured data type name using which the logical file pointers are declared in C programs. Whenever a file is to be operated for input or output operations the pointer variable of the type FILE is used. We discuss such FILE pointer in the next article in detail.

File System Basics

The hard disk drive used as secondary storage device in the computing system provide  place to store data. The only way to store and access data on a hard disk drive is by either specifying the data’s physical location in terms of cylinder, head, and sector or by its logical location the block number on the disk. For a programmer specifying and referring the data like this is too difficult. So the operating system takes care of this by means of providing a good file system.

The operating system easily keeps track of the things stored on disks. It is nothing but a way of filing data in an easily accessible way. This is the major role played by the file system. In order to access such data on the disk the programmer is required to write ‘file-handling’ programs. The data on the secondary storage is stored only by means of file.

With reference to Operating System like "Linux", a File System is the whole structure in which the FILES are organized, stored and named especially for the users of the system.

File system treats different sets of data as files. Each file is separate from the other. Along with the A data stored within it, the file system includes additional information for each file like

• The name of the file.
• The access permissions on the file
•  The time and date of creation, access, and modification of the file.

Using the available file system the user or many users can create many files. When all these files are at one place the identification is difficult for the users. The file system provides certain mechanism to make it easier to group related files together. The most commonly used mechanism is the directory structure’. The directory structure or simply directory is regularly implemented as a special type of file. The directories make it possible to create hierarchical structures of files and sub directories.

The file systems vary in implementation details. It means that all the file systems cannot be accessed by all the operating systems. The operating system ‘Linux’ includes support for many popular file systems. So, it is possible to access the file systems of other operating systems with ease. This is particularly useful in dual-boot scenarios, and when migrating files from one operating system to another.