1Build a class called TestExceptionsjavaPut the following co

1.Build a class called “TestExceptions.java”.Put the following code in the main method.

int myArr = new int[10];

int x,y,z;

x=0;

y=10;

z=y/x;

myArr[10] = 0;

Compile and run this class.   What happens?

          Now add try/catch blocks to catch these exceptions?

          Is there another way that you can prevent a run-time error without

                   using try-catch blocks?

2.next build an Account class.The Account class should have 3 Properties: Balance, Owner and AcctNo.The Account class should have 2 constructors, one that takes all 3 properties and one that takes no args(the default).The Account class should have set and get methods as well as deposit and withdraw methods.Also include a display() method that outputs AcctNo, Owner and Balance. Use a main() method to test out this class.

Use the following code, in the main method, to test the Account class?

Account a1;

a1 = new Account(2222, “Frank”, 1000);

a1.deposit(100.00);

a1.display();

3.now in your Account main() method, attempt to withdraw more than the current balance that is available.What happens now?

Use the following code to test the Account class?

Account a1;

a1 = new Account(2222, “Frank”, 500.00);

a1.deposit(100.00);

a1.withdraw(900.00);

a1.display();

          What happened?

Solution

a)

If we compile the code as given following exception occurs:

Exception in thread \"main\" java.lang.ArithmeticException: / by zero
   at TestExceptions.main(TestExceptions.java:9)

Now by adding try and catch statement, modified code:

TestExceptions.java

public class TestExceptions
{
public static void main(String[] args)
{
   int myArr[] = new int[10];
   int x,y,z;
   x=0;
   y=10;
   try
   {
   z=y/x;     
}
catch(ArithmeticException e)
{
       System.out.println(e);
}

   myArr[9] = 0;
}
}

Another way that you can prevent a run-time error:

public class TestExceptions
{
public static void main(String[] args)
{
   int myArr[] = new int[10];
   int x,y,z;
   x=0;
   y=10;
   if(x!=0)
   {
   z=y/x;     
}
else
{
       System.out.println(\"Divide by zero Exception\");
}

   myArr[9] = 0;
}
}

b)

Account.java

public class Account
{
public String owner ;
public double balance;
public int accnumber;

public Account(int accnumber, String owner , double balance) {
this.owner = owner;
this.balance = balance;
this.accnumber = accnumber;
}
public Account() {
this.owner = \"Defaulname\";
this.balance = 0;
this.accnumber = 0;
}

   public void getBalance()
   {
   System.out.println(\"Your balance is \" + this.balance);   
   }

   public void setBalance(int b)
   {
       this.balance = b;
   }

   public void deposit(double amount)
   {
   this.balance = this.balance + amount;
   }

   public void display()
   {
   System.out.println(\"Owner: \" + this.owner);   
   System.out.println(\"balance: \" + this.balance);   
   System.out.println(\"Account Number: \" + this.accnumber);   
   }

   public void withdraw(double amount)
   {
       if( amount > this.balance)
       {
       System.out.println(\"Sorry, you have insufficient balance!\");   
   }
   else
   {
   this.balance = this.balance - amount;        
   }
   }
}

driver.java

public class driver
{
public static void main(String[] args)
{
Account a1;
a1 = new Account(2222, \"Frank\", 1000);
a1.deposit(100.00);
a1.display();
}
}

Sample output:

Owner: Frank
balance: 1100.0
Account Number: 2222

c)

driver.java

public class driver
{
public static void main(String[] args)
{
Account a1;
a1 = new Account(2222, \"Frank\", 500.00);
a1.deposit(100.00);
a1.withdraw(900.00);
a1.display();
}
}

Sample Output:

Sorry, you have insufficient balance!
Owner: Frank
balance: 600.0
Account Number: 2222