Force.com Platform Fundamentals: Apex Data Types

Force.com Platform Fundamentals: Apex Data Types

Apex Data Types include:

  • Primitive
  • Enum
  • sObject
  • Collection

 

Primitive Data Types:

Include the following:

  • Boolean
  • Date
  • Date/Time
  • Time
  • ID
  • Integer
  • Long
  • Double
  • Decimal
  • String
  • Blob
  • Object

 

Enum Data Types

  • Is an abstract data type that allows you to store the values of a finite set of identifiers
  • Defined using the keyword ‘enum’
  • Built-in enums viz. System.StatusCode returns API error codes
  • Some enum methods:
    • Values() – returns a list of values for the enum
    • Name() – returns the name of the enum

 

sObject Data Types

  • Represents Objects (Standard and Custom) in Salesforce.com
  • Can be either strongly typed or loosely typed
  • Initialized to null by default
  • Can be instantiated with <name, value> pairs
  • Possible to declare variables of generic sObject data types. e.g.
    • sObject obj = new Account(); //obj instantiation
    • Account acct = (Account)obj; // type-casting
    • sObject[] acc = new Account[0];
    • List<Account> accnt = List<Account> acc; //List of Accounts

 

Collection Data Types

Three different collections: List, Set, Map

  • A List is an ordered collection of a single type
    • List<Integer> iList = new List<Integer>(); iList.add(1); iList.add(‘String’); // not allowed
    • Supports common methods like add, remove, clear, get, sort, isEmpty, size
  • A Set is an un-ordered collection of unique data
    • Set<Integer> iSet = new Set<Integer>(); iSet.add(1); iSet.add(2); iSet.add(3); iSet.add(2); //not allowed
    • Supports common methods like add, remove, clear, get, sort, isEmpty, size, remove, removeAll, contains, containsAll
  • A Map (Hash-Map) is an un-ordered collection of unique keys that map to single values
    • <Key, Value> pair
    • Keys and Values can be of any data type including other collections from the above list
    • Often used to map ID’s to sObjects
    • Supports common methods like add, remove, clear, get, sort, isEmpty, size, remove, removeAll, contains, containsAll, containsKey, keySet, values, put, putAll
    • Map<Integer, String> map = new Map<Integer, String>();  map.put(1, ‘One’); map.put(2, ‘Two’);

 
[message_box title=”Salesforce.com Certified” color=”blue”]From the small business to the large enterprise, we have solutions to help improve win rates.[/message_box] Contact Us

Leave a Reply

Your email address will not be published. Required fields are marked *