Assume Three Threads Share a BankAccount Object with Balance of Zero

question 68

Multiple Choice

Assume three threads share a BankAccount object with balance of zero (0) , a ReentrantLock named myLock, and has a condition object on myLock named lowBalanceCondition, as shown below. Thread one calls withdraw(30) , then thread two calls withdraw(20) and thread three calls deposit(45) . If the starting balance is 0, what is the balance after the three calls and after the waiting threads have had a chance to run? public void deposit(int dollars)
{
MyLock.lock() ;
Int newBalance = balance + dollars;
System.out.println("depositing") ;
Balance = newBalance;
LowBalanceCondition.signalAll() ;
MyLock.unlock() ;
}
Public void withdraw(int dollars)
{
MyLock.lock() ;
While (balance < dollars)
{
LowBalanceCondition.await() ;
}
Int newBalance = balance - dollars;
System.out.println("withdrawing") ;
Balance = newBalance;
MyLock.unlock() ;
}

• A) 0
• B) 15 or 25
• C) 45
• D) -5

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