Tutorial 4. public class Stock { private int numberofshares; private double dividend; private String TickerSymbol;

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1 Tutorial 4 1- Based on the following UML create the Stock class Stock - numberofshares:int - TickerSymbol:String - dividend:double +getnumberofshares():int +gettickersymbol():string +getdividend():double +setnumberofshares(n:int) +settickersymbol(s:string) +setdividend(d:double) public class Stock { private int numberofshares; private double dividend; private String TickerSymbol; public void setnumberofshares(int n) { numberofshares = n;} public void setdividend(double d) { dividend = d;} public void settickersymbol(string s) { TickerSymbol = s; } public int getnumberofshares() { return numberofshares; } public double getdividend() { return dividend;} public String gettickersymbol() { return TickerSymbol;} } 2- In the flowing class a. Create an object of type Stock. b. Call the getnumberofshares method.

2 c. Call the setnumberofshares method public class StockTest { Public static void main (String[] arg) { // Answer for 2.A Stock S=new Stock(); //Answer for 2.b System.out.print( S. getnumberofshares() ) ; //Answer for 2.c S. setnumberofshares(7); 3- Add a parameterized constructor to class Stock. Public Stock(int a, String n, double d) { numberofshares=a; dividend=d; TickerSymbol=n;} 4- After adding a constructor to class Stock, is the way of creating object in question 2.a still valid? Explain. No, Because before adding the constructor in question 3 we relied on the default constructor. But after adding a constructor, the default constructor is not there any more, and to create an object we should create an object based on the available constructor So the object should be created as follow if we added the constructor in question 3 Stock S=new Stock(9, milk,3.0); 5- Fill up the blank. The -private -members of a class are not directly accessible outside the class.

3 The --public --members of a class are accessible outside the class. A class that creates an object of another class, then calls the object s methods, is a - Driver Class nextline -- reads characters until a newline character is encountered, then returns the characters as a String. --next ---reads characters until any white-space character is encountered, then returns the characters as a String. Instantiating an Object using Keyword ---new--and Constructors. - A constructor - similar to a method but is called implicitly by the new operator to initialize an object s instance variables at the time the object is created. A local variable is declared inside a.---class or a method parameter or inside a block The default value for an instance variable of type String is ----null Evaluate if the following sentences are true or false. The name of a constructor is the same as the name of the class ( T ) The set method is declared with parameter ( T ) When a method terminates, the values of its local variables are lost ( T ) The keyword void indicates that a method will perform a task but will not return any information( T ) Local variables are not automatically initialized ( T ) A local variable has no access modifier ( T ) 7- Write the definition of a class that has the following properties and draw the UML diagram

4 Answer: public class secert{ // four instant variables private String name; private int age; private int wieght; private double highet; // starting methods sections public secert(){// this is a default constructor name= ""; age=0; wieght=0; highet = 0.0;} public secert(string s, int i, int r, double d){// this is a parameter constructor name= s; age=i; wieght=r; highet = d;} public void setname(string n ){// set Name method name=n;} public void setage(int a ){// set age method age=a; } public void setwieght(int w){// set wieght method wieght=w;} public void sethight(double d ){// set hieght method highet=d;} public String getname(){// get name method return name;} public int getage( ){// get age method return age; }

5 public int getwieght(){// get wieght method return wieght;} public double gethight(){// get hieght method return highet;} }// end of class secert - name:string - age:int - weight:int - length:double <<constructor>> secret(n:string, i:int, r:int, d:duble) +setname(n:string) +setage(a:int) +setweight(w:int) +sethight(d:double) +getname():string +getage():int +getweight():int +gethight():double