declaring and instantiating objects

[adithi gudipudi]

hello All,
I have a class Item to and I want to create array of this.
If I do
Item items[3];
items[0]= new Item();
.....
items[0].setItemID(1);
....
is this not correct...
Please help
Thanks
adithi

[Vad Fogel]

Welcome to JavaRanch, adithi!
You can't declare an array specifying its size like this: Stuff myStuff[n];
If you change it to

Stuff[] myStuff=new Stuff[3]; 

it should work. Or, in two lines:

  
Stuff myStuff[];
myStuff=new Stuff[3];

[ October 20, 2003: Message edited by: Vad Fogel ]

[Corey McGlone]

Originally posted by adithi gudipudi:

Item items[3];
items[0]= new Item();

You're close, but you actually have to create the array object, not just declare it. Like this:

Item[] items = new Item[3];

I hope that helps.

[adithi gudipudi]

Thanks for the quick replies..But
if I do like this...
Item[] items = new Item[3];
items[0]= new Item("ItemID1","ItemName1");
it gives me compiler error
why so?
Thanks
adithi

[Vad Fogel]

It's hard to say why without seeing the code. Maybe, you're not matching the Item constructor's arguments, maybe, Item class is not visible from where you wanna create it, maybe... 1000 and one reasons. Examine the compiler error carefully, it must have a good hint.

[adithi gudipudi]

Hi I get this message when I compile it..
First.java:13: ']' expected
items[0]= new Item("ItemID1","ItemName1");
^
First.java:13: <identifier> expected
items[0]= new Item("ItemID1","ItemName1");
^
First.java:13: cannot resolve symbol
symbol : class emp
location: class First
items[0]= new Item("ItemID1","ItemName1");
^
3 errors
I have declared a constructor Item(String ID, String Name) so this should work I assume...
Thanks
Lakshmi.

[Vad Fogel]

If you post your code, we'll see the error clearer. Make sure class emp is accessible from class First, make sure that the array of Items is created inside the scope of the assignment.

[Anish Doshi]

Hey,
The problem is dat u have just created an array refrence but u have'nt created and array object yet. i mean u have done this:
Item items[3]; \\ Array refrence created but wont compile coz u \\shouldn't specify lngth der
Item items[] = new Item[3]; \\ Array Object created.
Untill u do not create an array object u would not b able to use d array itself. Then u can create ur object like:
items[0] = new Item; \\ Your object created.
Then u can use it like:
items[0].setItemID(1);
I hope diz mght help you. Bye.
Kind Regards,
Anish Doshi.

[adithi gudipudi]

Hi all,
This is my program.
I want to create an Array of Item and use the constructor I have ( 2 parameters ).

------------------------
public class Temp
{
public static void main(String args[])
{
Item item1= new Item(1,"Item 1");
System.out.println(" the Item I details are "+ item1.getItemID()+".\n The info is "+item1.info);
}
}

class Item
{
private int ItemID;
public String info;

public Item(int ID, String info)
{
ItemID= ID;
this.info=info;
}


public int getItemID()
{
return ItemID;
}
}
----------------
I want to add some thing like
Item[] items= new Item[3]; but I want to initialize the elements also to different values. I checked different books but could find no information about this.
Thanks much
Adithi.

[Michael Zalewski]

Use braces and drop the size

Item[] items= new Item[] {
    new Item( 1, "Item 1")
  , new Item( 2, "Item 2")
  , new Item( 3, "Item 3")
}; 

[Arulkumar Gopalan]

check this ...
----------------------------------
public class TempItem
{
public static void main(String args[])
{
Item arrItem[] = new Item[3];
for(int i=0;i<arrItem.length;i++)
{
arrItem[i] = new Item(i,"Item "+i);
System.out.println(" the Item "+ i +" details are "+ arrItem[i].getItemID()+".\n The info is "+arrItem[i].info);
}
}
}

class Item
{
private int ItemID;
public String info;
public Item(int ID, String info)
{
ItemID= ID;
this.info=info;
}

public int getItemID()
{
return ItemID;
}
}
----------------------------------

[adithi gudipudi]

Thanks Michael,
One more questions, If I dont declare the constructor and want to use the default one.
then saying
Item items = new Item[3];
...
would do all the work right? I dont have to do anything else.
Thanks again for you help
adithi