Re: Newbie Question - ArrayLists and referencing it
On Nov 10, 5:50 pm, Taria <mche...@hotmail.com> wrote:
Hello all,
I've tried many different ways to assign a value to the position of my
choice in a data structure, ArrayList and would appreciate any hints
how to do this. My program as follows (short version):
import java.util.*;
public class MyProg1 {
public static void main(String[] args) {
ArrayList data = new ArrayList();
You are using an "unchecked" ArrayList here, try:
"ArrayList<Integer> data = new ArrayList<Integer>();"
ArrayList [] table = new ArrayList[5];
data.add(1);
data.add(3);
data.add(4);
for ( int i = 0; i < 3; i++ ){
//table.add(data.get(i)); //these are 3 different
failed ways that I've tried
//table[i]=data.get(i);
//table(i)=data.get(i);
Wrong syntax, and trying to assign to empty elements.
table[0] = data;
}
}
Essentially, I want to assign the first value of data to the first
element of table, the second value of data to table(2,0), and 3rd
element to table(3,0). The statement table[0] = data puts the whole
arrayList data to table(0) which is not what I want. How do you
reference the elements of table? I thought I understood the
referening until now. :x
Any help is appreciated.
You are going to get a lot of warnings using "unchecked"
arrays, but you can reduce that a little bit as follows:
public class MyProg1
{
public static void main( String[] args )
{
ArrayList<Integer> data = new ArrayList<Integer>();
ArrayList table[] = new ArrayList[ 5 ];
Arrays.fill( table, new ArrayList<Integer>() );
data.add( 1 );
data.add( 3 );
data.add( 4 );
for( int i = 0; i < data.size(); i++ ) {
table[ i ].add( i, data.get( i ) );
}
}
}
To suppress the warnings completely, you will (AFAIK),
need to use an annotation, or use the '-nowarn' flag
at the command line.
--
Chris