array with elements of different types?

[Vince Aggrippino]

I'm working on my first Java program, for practice. It's a text editor and I want to be able to have a configuration file to store settings like font, color, window size, etc... I'm not having any problem with opening/reading the file or creating the interface for changing the settings. However, I'd like to store all of these settings in one variable.

Array probably isn't the right thing. Is this a Collection? I have lots of reading materials, but no experience.

For example, my settings include Objects for a Font (just one, I'm using JTextArea for now), several Colors (foreground, background, etc.), several integers (window width/height), and several boolean flags (remember size/location of window).

Thank you,
Vince

[ak pillai]

Create a Class called Config and store your values as key/value pairs on a HashMap within your config class and provide accessor methods read relevant data.

[Vince Aggrippino]

Thank you. I've read through the API for HashMap and that is the best solution in this case.

My original question wasn't well thought-out. I wanted to store objects of different types in an array, but I'm reading them from a text file, so they have to start out as Strings anyway.

I'm still curious, though... Is there a type of array that can contain elements that aren't all the same type? I mean, with HashMap, it looks like I can have an associative array with keys of one type and values of another type, but those values would all have to be of the same type. If it was

HashMap<String, Integer> settings = new HashMap<String, Integer>;

, all of the values have to be Integers, don't they? I couldn't

settings.put( "RememberWindowSize", true );

, could I?

Thank you,
Vince

[Shaan Shar]

Originally posted by Vincente Aggrippino:
Thank you. I've read through the API for HashMap and that is the best solution in this case.

My original question wasn't well thought-out. I wanted to store objects of different types in an array, but I'm reading them from a text file, so they have to start out as Strings anyway.

I'm still curious, though... Is there a type of array that can contain elements that aren't all the same type? I mean, with HashMap, it looks like I can have an associative array with keys of one type and values of another type, but those values would all have to be of the same type. If it was

HashMap<String, Integer> settings = new HashMap<String, Integer>;

, all of the values have to be Integers, don't they? I couldn't

settings.put( "RememberWindowSize", true );

, could I?

Thank you,
Vince

Actually what i understand about your question is, you want to store any type of information in HashMap.

HashMap<String, Integer> settings = new HashMap<String, Integer>;

, all of the values have to be Integers, don't they? I couldn't

settings.put( "RememberWindowSize", true );

there is no constructer in HashMap through which you can decide what the element types in HashMap should be..

Actually if you have gone through HashMap API's then you must know that HashMap stores data in format.

HashMap hm = new HashMap();
hm.put(Object o1,Object o2);

So if you want to store any primitive data and you are using Jdk1.4 then you have to typecast it in it's Wrapper Class object(In jdk1.5 it's done automatically by autoboxing).. else otherwise everything in JAVA is in form of Object..

That's solve your problem..

Hope it helps you.

if still any concern then revert back ....

[Garrett Rowe]

there is no constructer in HashMap through which you can decide what the element types in HashMap should be..

Actually in Java 1.5 it is possible to specify what types are stored in a HashMap (or most any other Collection) using generics. This is generally regarded as a *good thing* as it offers compile time type checking which guarantees type safety. The class source is declared as

public class HashMap<K,V>
    extends AbstractMap<K,V>
    implements Map<K,V>, Cloneable, Serializable
{
 //...
}

[Justin Fox]

i think, a Doubly linked list(collection) would be better, thats just me,

because each node can have several values that you can store in each node..

and the next and prev pointers, would help you access these nodes easily..

throw in a findinList() method, and you're done..

you can findinList(Color a);

findinList (int width);

anything...

and the cool thing about linked lists (doubly) is that you can, in a way,

just link the values together, for instance..

    
public class Collection
{
 public class Node
{
   private Color color;
   private int Width;
 
   private Node nextColor, prevColor, nextWidth, prevWidth;
 
      public Node()
      {
           color = Color.black(); // not sure if correct
           Width = 0;
        
           nextColor = prevColor = nextWidth = prevWidth = null;
       }
}
          
}
 

then you can add your addNode() method, and you can also overRide the method, so you can addNode(int), addNode(int, color), addNode(color);

Justin;