How to shift index in a table
Hey,
My program collects 5 pieces of information per object from user. Some of the input data is in String format, rest are Integers. I create an object from this data and put in into a table. My table contains max 10 pieces of information.
I have editing options for this data, which are erase one or all pieces, or modify a piece. I erase data by simply setting the index to null. Erasing one piece is incomplete atm, here's why:
Say I have 5 pieces in table, and I erase the one with index of 0. I can't print my information because the table starts with a null value:
int index = 0;
if (table[index] !=null){ System.out.println(data);}
..
My guess is that I can solve this problem by decreasing the index of pieces greater than the modified one by 1. I can imagine that I'll be using for loop here. This is where I run out of ideas: is it possible to just modify the index, or do I have to rewrite the data again?
Any help is appreciated,
br,
nomi
[1177 byte] By [
nomikaia] at [2007-11-26 13:56:43]
I think using for loop would be the easiest way (?). I'm filling the table as simply as:
items[index] = new table (value, quality..);
Using LinkedList seems a bit far fetched for me. But again, if I am to use for loop, I think I would have to rewrite the data to appropriate index?
I suggest to do one alternate method which we will do in actual database also, to save all deleted datas
Add one more boolean field in ur table object named "isExists". When u delete a record change that value to false. When reading from table, take only records with isExists = true
But here also, when the number of records exceeds the limit, you need to delete the records with isExists = false
Cheers
> I think using for loop would be the easiest way (?).
> I'm filling the table as simply as:
> items[index] = new table (value, quality..);
>
> Using LinkedList seems a bit far fetched for me. But
> again, if I am to use for loop, I think I would have
> to rewrite the data to appropriate index?
Why is a List far fetched? Type of List you pick depends on how you use the list (whether you want RandomAccess, etc.).
List items = new ArrayList(); // or LinkedList
items.remove(index); // Remove the item at index.
To use an array:
Table [] items = new Table[20]; // whatever size
items[index] = new Table(value, quality, ...);
// To remove:
System.arraycopy(items, index, items, index+1, items.length-(index+1));
items[items.length-1] = null;
