Array question.

Hi,

I have 2 questions:

#1) How do you check if the array is empty?

#2) How do you continue to get the item of the last element of the array? Assumingly the array is not empty.
Example: myArray[] FACES = {"10","J","Q","K","A"}; I'd like to get the values in the array and print them out in the reverse order. A,K,Q,J,10.

Thanks

Code:

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#1) if(array==null)

#2) for (int i = FACES.length - 1 ;i => 0 ; i++){
          FACES[i];
      }

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Is it possible to have an array that's empty but not null ie array.length==0

you mean like

Code:

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int[] array = new int [0] ;

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Thank you!

for the question #2, I did exactly what you said and I got an error message "Illegal start of expression".

Quote:

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Originally Posted by AlnavPlatinum

for the question #2, I did exactly what you said and I got an error message "Illegal start of expression".

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Show me your code

public Card drawCard()
{

if(cards!= null)
{
for(int intCnt = cards.length - 1; intCnt => 0; inCnt++)
{
cards[inCnt];
}
}

}

The execution line stops at:for(int intCnt = cards.length - 1; intCnt => 0; inCnt++)

http://img400.imageshack.us/img400/8008/oops7yt.gif

Code:

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for(int intCnt = cards.length - 1; intCnt >= 0; inCnt++)

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how stupid I was, So so http://imagehost.biz/ims/pictes/209208.gif

Got it.. Thanks

Code:

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boolean notFull = false;
for(int i = 0; i < arrayName.length; i+)
{
        try{
                Object o = arrayName[i];
        }catch(NullPointerException ex)
        {
                notFull = true;
        }
}

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That will tell you if there are any empty elements.

No, it won't. Just accessing and storing the reference does not throw a null pointer exception. The only way your code can catch one is if the array itself is null.
Also, exceptions should never be used for normal computation tasks.

Just compare each element to null.

I take that back then, I had not tested it, I thought it would work.
If the variable in the array is null why wouldn't it throw a NullPointerException?

If you tried using the "o" var it would have. but since you didn't do anything to upset the JVM it'll stay putt

Code:

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for(int intCnt = cards.length - 1; intCnt >= 0; inCnt++)

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should be:

Code:

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for(int intCnt = cards.length - 1; intCnt >= 0; intCnt--)
{
  System.out.print (cards[intCnt]);
}

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Otherwise it would be an infinite loop, intCnt would always be greater than 0. (that is assuming you just made a typo on your last variable name and it's supposed to be intCnt not inCnt, if it's not a typo, then ignore this.)