Page 351 - computer science (868) class 11
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Step 3:  Read data to the file using different read methods for different data types inside a try-catch block. When the end of file is
                            met, an EOFException is generated which is handled by the catch block.
                       Step 4: Close all the stream objects using close() method.
                    3.  Write the steps to write data to a character file.
                   Ans.  Step 1:  Create an object of FileWriter class and connect it with the physical file in the disk. If the file does not exist, then it is
                            created by default.
                       Step 2:  Connect the FileWriter object with the BufferedWriter object. Buffers are the temporary storage areas where the output
                            stream is first stored.
                       Step 3: Now, link the BufferedWriter object with the PrintWriter object for writing characters to the text file.
                       Step 4: Write the text onto the file by using print() or println() method.
                       Step 5: Lastly, close all the stream objects using the close() method.
                    4.  Explain the three parts of System.out.println().
                   Ans.  •  System: It is a final class (a class that does allow other classes to inherit its features) defined in java.lang package.
                        •   out: It is a class variable of PrintStream type, which is a public static member of the System class. Since it is a static member, it
                        is accessed using the class name, hence System.out is referenced.
                        •   print() or println(): These are public methods of PrintStream class. Since out is of PrintStream type, it is used to call the
                        methods print() and println().
                    5.  Define a class Stock having the following class description.
                        Data Members
                        productC        :  Product code of product type integer
                        productN        :  Product name of String type
                        price           :  Product price of type double
                        quantity        :  Quantity in stock of type int
                        reorder         :   Reorder level of type int. When quantity in stock falls below reorder level, fresh order for buying the
                                           item is to be placed.
                        Member Methods
                        void createFile()   :  Creates a binary file Product.dat having the fields mentioned above as data members
                        void readRec()   :  Reads and prints all the records in the file Product.dat
                        void printReorder()  :  Prints details of the items which are below reorder level
                        void editPrice()   :  Updates the price of an item based on the item number
                        void delRec()   :  Deletes an item from stock based on the item number
                        void addItem()   :  Increases the quantity of the item in stock when a new item is purchased
                        void sellItem()   :  Decreases the quantity of the item in stock when an item is sold
                        static void main()   :  Writes a menu-driven program to perform the above file operations
                   Ans.  import java.util.*;
                       import java.io.*;
                       class Stock
                       {
                           String productN;
                           int productC,quantity,reorder;
                           double price;
                           Scanner sc=new Scanner(System.in);
                           void createFile() throws IOException  // Creating file Product.dat
                           {
                               FileOutputStream fout=new FileOutputStream("Product.dat",true);
                               DataOutputStream dout=new DataOutputStream(fout);
                               char ch='y';
                                   while(ch=='y' || ch=='Y')
                                   {
                                   System.out.println("Enter product code");

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