java.lang.IllegalThreadStateException

[Urs Waefler]

Hi

This is my code:

class Account
{
    private float balance;

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

    public float getBalance()
    {
        return balance;
    }
}

class Bank
{
    private Account[] account;

    public Bank()
    {
        account = new Account[100];
        for(int i = 0; i < account.length; i++)
        {
            account[i] = new Account();
        }
    }

public void getMoney(int accountNumber, float amount)
{
    synchronized(account[accountNumber])
    {
        float oldBalance = account[accountNumber].getBalance();
        float newBalance = oldBalance - amount;
        account[accountNumber].setBalance(newBalance);
    }
}

public void transferMoney(int accountNumber, float amount)
{
    synchronized(account[accountNumber])
    {
    	float newBalance;
    	float oldBalance = account[accountNumber].getBalance();
        if(this.equals("Andrea"))
        newBalance = oldBalance + amount;
        else
        newBalance = oldBalance - amount;
        account[accountNumber].setBalance(newBalance);
    }
}
}


class Clerk extends Thread
{
	private Bank bank;

    public Clerk(String name, Bank bank)
    {
        super(name);
        this.bank = bank;
        start();
    }

    public void run()
    {
        
            /*
             * set account number
             */
            int accountNumber = 0;

            /*
             * set transfer amount
             */
            float amount = 100;
            
            for(int i = 0; i <= 1000000; i++){
            bank.transferMoney(accountNumber, amount);
            }
        
    }
}

public class Banking
{
    public static void main(String[] args)
    {
        Bank myBank = new Bank();
        Clerk Andrea = new Clerk("Andrea", myBank);
        Clerk Petra = new Clerk("Petra", myBank);
        Andrea.start();

    }
}

I do not understand java.lang.IllegalThreadStateException? How should I correct my code?

Regards, Urs

[William Brogden]

Where is the rest of the Exception stack trace? That information is generated to help you understand the cause, don't throw it away.

Bill

[Urs Waefler]

It looks like that:

Exception in thread "main" java.lang.IllegalThreadStateException
at java.lang.Thread.start(Unknown Source)
at Banking.main(Banking.java:93)

How can I correct this issue?

[Raaghu Kannan]

You are starting the same thread twice

Once in Clerk Constructor
Once in your main method.

Remove one of them , better to remove from Constructor.

Thanks and Regards
Raaghu.K