Apex Design Patterns

Ignoring the equals() and hashcode() methods while performing object comparison

Consider the following Apex class:

global class DealInfo {     
    public Integer amount {get;set;} 
    public String amountCurrency {get;set;}  
} 

Now, we are in a situation where we need to sort a list of objects from the preceding class. Let's run the following anonymous code:

DealInfo o = new DealInfo(); 
o.amount = 200; 
o.amountCurrency = 'USD'; 
 
DealInfo o1 = new DealInfo(); 
o1.amount = 100; 
o1.amountCurrency = 'USD';  
List<DealInfo> lstDeals = new List<DealInfo>{o,o1}; 
lstDeals.sort(); 

If you are expecting the list to get sorted, then it's not so. We get the following error from Apex:

System.ListException: One or more of the items in this list is not Comparable. 

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