Synchronizing Object Access

• If code between calls to lock and unlock throws an exception, call to unlock never happens
• To overcome this problem, place call to unlock into a finally clause:

  public void deposit(double amount)
  {
     balanceChangeLock.lock();
     try
     {
        System.out.print("Depositing " + amount);
        double newBalance = balance + amount;
        System.out.println(", new balance is " + newBalance);
        balance = newBalance;
     }
     finally
     {
        balanceChangeLock.unlock();
     }
  }