Problems with vectors

[Sal Velinus]

What's wrong with this vector/iterator code? When it was coded as an array, it was ok. Everything compiles ok till here:

  {
        int totalRam = 0;
//        MemoryChip[] tmpRam = getRam();
          Vector tmpRam = getRam();
//        for (int i = 0; i < tmpRam.length; i++)
//        {
//            totalRam += tmpRam[i].getSize();
//        }
          Iterator chip = tmpRam.iterator();
          while (tmpRam.hasNext())
          {
              totalRam += next().getsize();
          }    
          
        return ("Computer with " + totalRam + " MB ram");
    }

Here's the error message:

inventory\Computer.java:76: cannot resolve symbol
symbol  : class Iterator
location: class inventory.Computer
          Iterator chip = tmpRam.iterator();
          ^
inventory\Computer.java:77: cannot resolve symbol
symbol  : method hasNext  ()
location: class java.util.Vector
          while (tmpRam.hasNext())
                       ^
inventory\Computer.java:79: cannot resolve symbol
symbol  : method next  ()
location: class inventory.Computer
              totalRam += next().getsize();  

Thanks.

[Michael Yuan]

Did you remember to import java.util.*?
Did you use JDK 1.2 and above?

[Sal Velinus]

Ok, got it down to one error, but can't figure it out.

public String toString()
    {
        int totalRam = 0;
//        MemoryChip[] tmpRam = getRam();
          Vector tmpRam = getRam();
//        for (int i = 0; i < tmpRam.length; i++)
//        {
//            totalRam += tmpRam[i].getSize();
//        }
          Iterator chip = tmpRam.iterator();
          while (chip.hasNext())
          {
              totalRam += (chip.next()).getsize();
          }    
          
        return ("Computer with " + totalRam + " MB ram");
    }

The error code now:

inventory\Computer.java:79: cannot resolve symbol
symbol  : method getsize  ()
location: class java.lang.Object
              totalRam += (chip.next()).getsize();  

getSize() is a method defined in class MemoryChip, which is in the same package and which is referenced in several other places in this class w/o problem.
The vector here holds MemoryChip objects. My thinking is that (chip.next()) should refer to an element in the vector of type MemoryChip, and so return getSize(). Doesn't work. Thanks for the help.
[ April 03, 2002: Message edited by: Greg Adams ]

[Valentin Crettaz]

Are you sure the case is correct?
In the compiler error, I see a getsize (lowercase 's') and you are talking about getSize (uppercase 's'). May that be the reason?

[Michael Yuan]

Your Iterator.next() method returns an "Object" type. You have to cast it back to "MemoryChip" before the compiler can check the "getsize()" method for you.
Try this:
totalRam += ((MemoryChip) chip.next()).getsize();
[ April 03, 2002: Message edited by: Michael Yuan ]

[Sal Velinus]

Thank you both, that cleared up the problem.