Date: AIM. Write a Java program to demo simple inheritance PROCEDURE

Transcription

1 Ex.No 7 Date: AIM INHERITANCE Write a Java program to demo simple inheritance PROCEDURE 1. Create a class stud which includes student name,major,year, rollno. 2. Create a class mark which extends the stud class and includes the following fields. 3. Read the input value and assign it to the respective class member variables. m1,m2,m3,m4,m5 and tot. 4. Read and Display the values which are assigned to the class members earlier. 5. Compile and run the program PROGRAM import java.io.*; class stud String name,major,year; int rollno; void input(int sroll,string sn,string mj,string yr) rollno=sroll; name=sn; major=mj; year=yr; class mark extends stud int m1,m2,m3,m4,m5,tot;

2 String result; void get(int mk1,int mk2,int mk3,int mk4,int mk5) m1=mk1; m2=mk2; m3=mk3; m4=mk4; m5=mk5; void total() tot=m1+m2+m3+m4+m5; void reslt() if((m1>50)&& (m2>50)&&(m3>50)&&(m4>50)&&(m5>50)) result="pass"; else result="fail"; void display() System.out.println("\t\tStudent Details"); System.out.println("Rollno:\t"+rollno); System.out.println("name:\t"+name); System.out.println("major:\t"+major);

3 System.out.println("year:\t"+year); System.out.println("Marks:\t"+m1+" "+m2+" "+m3+" "+m4+" "+m5); System.out.println("Total:\t"+tot); System.out.println("Result:\t"+result); class student public static void main(string args[])throws IOException mark m=new mark(); DataInputStream d=new DataInputStream(System.in); System.out.println("Enter Your Details"); System.out.println("Enter Name"); String name=d.readline(); System.out.println("Enter Rollno"); int rollno=integer.parseint(d.readline()); System.out.println("Enter Major"); String major=d.readline(); System.out.println("Enter year"); String year=d.readline(); System.out.println("Enter 5 Marks"); int m1=integer.parseint(d.readline()); int m2=integer.parseint(d.readline()); int m3=integer.parseint(d.readline()); int m4=integer.parseint(d.readline());

4 int m5=integer.parseint(d.readline()); m.input(rollno,name,major,year); m.get(m1,m2,m3,m4,m5); m.total(); m.reslt(); m.display(); Output: Z:\javaprog> javac student.java Z:\javaprog> java student

5 Ex.No 7 Date: AIM USAGE OF this KEYWORD Write a Java program to demo the usage of this keyword PROCEDURE 1. Create a class called addition which include the member a and b. 2. Create the constructor to initialize the objects. 3. Create an object and pass to values to the constructor. 4. Inside the constructor, we use this keyword, which refers the object. 5. Compile and run the program PROGRAM import java.io.*; class addition int a,b; addition(int a,int b) this.a=a; this.b=b; void sum() System.out.println("Addition"+(a+b)); class add

6 public static void main(string args[]) addition ad=new addition(10,20); ad.sum(); Output javac addition.java java addition

7 Ex.No 7 Date: AIM POLYMORPHISM Write a Java program to overload the constructor. PROCEDURE 1. Create the following classes with members a. Point b. Rectangle c. ConstrctOverLoad 2. Create the constructor for Rectangle class with different arguments. public Rectangle() origin = new Point(0, 0); public Rectangle(Point p) origin = p; public Rectangle(int w, int h) origin = new Point(0, 0); width = w; height = h; public Rectangle(Point p, int w, int h) origin = p; width = w; height = h; 3. Create an object and pass to values to the constructor. Rectangle rectone = new Rectangle(originOne, 100, 200); Rectangle recttwo = new Rectangle(50, 100);

8 4. Calculate the area of an rectangle. 5. Compile and run the program PROGRAM public class Point public int x = 0; public int y = 0; // a constructor! public Point(int a, int b) x = a; y = b; public class Rectangle public int width = 0; public int height = 0; public Point origin; // four constructors public Rectangle() origin = new Point(0, 0); public Rectangle(Point p) origin = p; public Rectangle(int w, int h) origin = new Point(0, 0); width = w; height = h; public Rectangle(Point p, int w, int h) origin = p;

9 width = w; height = h; // a method for computing the area of the rectangle public int getarea() return width * height; public class ConstrctOverLoad public static void main(string[] args) // Declare and create a point object and two rectangle objects. Point originone = new Point(23, 94); Rectangle rectone = new Rectangle(originOne, 100, 200); Rectangle recttwo = new Rectangle(50, 100); System.out.println("Width of rectone: " + rectone.width); System.out.println("Height of rectone: "+ rectone.height); System.out.println("Area of rectone: "+ rectone.getarea()) Output C:\javac ConstrctOverLoad.java C:\java ConstrctOverLoad Width of rectone: 100 Height of rectone: 200 Area of rectone: 20000

10 Ex.No 7 Date: CREATING JAR FILE AIM Create a jar file PROCEDURE 1. Create a class Count 2. Compile the class Count 3. Create a jar file using jar cvf Count.jar Count.class PROGRAM: import java.io.*; public class Count public static void countchars(inputstream in) throws IOException int count = 0; while (in.read()!= -1) count++; System.out.println("Counted " + count + " chars."); public static void main(string[] args) throws Exception if (args.length >= 1) countchars(new FileInputStream(args[0])); else System.err.println("Usage: Count filename");

11 CHETTINAD COLLEGE OF ENGINEERING AND TECHNOLOGY-KARUR Output: Counted 9 chars. Create a JAR File Containing the Class File Next, create a JAR file containing the Count.class file. Type the following command window: jar cvf Count.jar Count.class This creates a JAR file, Count.jar, and places the Count.class file inside it.

12 CHETTINAD COLLEGE OF ENGINEERING AND TECHNOLOGY-KARUR Ex.No 7 Date: USER DEFINED EXCEPTION AIM Create a Bank account class and throw the user defined exception. PROCEDURE 1. Create a class InsufficientFundsException which extends Exception. 2. Create a class CheckingAccount which process the balance while withdraw the money. 3. Create a class BankDemo. 4. While withdraw operation, if insufficient money is withdrawn, immediately, user define message Sorry, but you are short is displayed 5. Compile and run the program PROGRAM: // File Name InsufficientFundsException.java import java.io.*; public class InsufficientFundsException extends Exception private double amount; public InsufficientFundsException(double amount) this.amount = amount; public double getamount() return amount; // File Name CheckingAccount.java import java.io.*; public class CheckingAccount private double balance;

13 CHETTINAD COLLEGE OF ENGINEERING AND TECHNOLOGY-KARUR private int number; public CheckingAccount(int number) this.number = number; public void deposit(double amount) balance += amount; public void withdraw(double amount) throws InsufficientFundsException if(amount <= balance) balance -= amount; else double needs = amount - balance; throw new InsufficientFundsException(needs); public double getbalance() return balance; public int getnumber() return number; // File Name BankDemo.java public class BankDemo public static void main(string [] args) CheckingAccount c = new CheckingAccount(101); System.out.println("Depositing $500..."); c.deposit(500.00); try

14 CHETTINAD COLLEGE OF ENGINEERING AND TECHNOLOGY-KARUR System.out.println("\nWithdrawing $100..."); c.withdraw(100.00); System.out.println("\nWithdrawing $600..."); c.withdraw(600.00); catch(insufficientfundsexception e) System.out.println("Sorry, but you are short $" + e.getamount()); e.printstacktrace(); Output C:\>javac BankDemo.java C:\>java BankDemo Depositing $ Withdrawing $ Withdrawing $ Sorry, but you are short $200.0