[SalesForce] Object class in Apex

I'd like to know if there is an idea of very base Object class in Apex, like we have it in Java or C#. Seem like it's supported, for example I can write something like the following in developer console and it works:

List<Object> test = new List<Object> {1, 'a'};

But I can't find any documentation about it. Does anyone know if it's officially supported?

Best Answer

There is a system class called Object that is the base for every other construct in the system. This class is completely useless except as a "void pointer" to other types of data. For example, we can store any type of data in an object, and we can use instanceof to retrieve the base type of the object.

static void dosomething(object source) {
    if(source == null) {
        return;
    }
    if(source instanceof integer) {
    ...
    }
    if(source instanceof map<string, integer>) {
    ... etc
    }

It appears to support two functions: hashcode() and equals(object). However, calling either method appears to crash the code and/or cause unexpected results (but they do compile and run). It is safe to use the standard equality operators, ==, !==, ===, and !==. You can safely use Object as a key or value in a map, set, or list. You cannot construct an object, as it is most likely defined as abstract.

There is no documentation on this class that I've ever seen; it's mentioned in various parts of the documentation, but only ever as a placeholder for generic type interfaces. Note that the compiler internally refers to this type as ANY. It's only as functional as it needs to be to allow polymorphic code.

Related Solutions

[SalesForce] Documenting Salesforce.com Apex class files

I have used apexDoc for a while and we are starting to roll it out more fully for our use at my organisation. It is open source software and so you could always contribute some updates for it :-) What features are you wanting to add to it that it doesn't have (just to give a flavour)?

In answer to your questions

1) I don't think anybody has successfully managed to do this. There is an idea of the ideas exchange for it to be done but it seems to gain very little support.

2) Theoretically it should be pretty easy as apex is a Java DSL. Have you tried running Doxygen and if so what errors does it throw up?

3) I use ApexDoc to generate some basic output and then have a little script tied in to copy across custom css and things. It isn't perfect but it does for the small amount we need at the moment.

I believe the IDE is being open sourced at some time in which case I would imagine the antlr grammar file would become available which may help you out.

I know it is not really an answer for what you wanted to hear per se, but sadly it's all we have atm (and I would love a nicer documentation generator!!)

Paul

[SalesForce] define a numbered Enum

Unfortunately not, but as long as you're happy with not being able to define the numbers yourself, and 0 based counting is good enough then you can use the enum method ordinal() which lets you know the index of the enum value you're currently referencing.

So if you declared your enum like so:

public enum OrderType
{
    Coop,
    Normal,
    Package,
    SubInvoicing
}

Then you calling OrderType.Normal.ordinal() would return an integer with value 1. Of course if you do need to specify numbers a somewhat hacky way would be to add placeholder entries within your list, but depending on the numbers you need that could get a bit crazy. Another alternative might be a public map:

public class OrderTypeMap
{
  private static Map<String, Integer> typeMap = new Map<String, Integer>
  {
    'Coop' => 0,
    'Normal' => 1,
    'Package' => 2,
    'SubInvoicing' => 3
  };

  public Integer Value(String s)
  {
    return typeMap.get(s);
  }
}

You could even combine that with an enum (if you really want the enum rather than a string) and use the name() enum method to pass into the map:

Integer i = OrderTypeMap.Value(OrderType.Normal.name());

Best Answer

Related Solutions

[SalesForce] Documenting Salesforce.com Apex class files

[SalesForce] define a numbered Enum

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