Salesforce | Sort “wrapper class” objects alphabetically based on a String parameter

Suppose we have a Wrapper class with fName as a string instance variable and we want to sort a list of objects alphabetically based on value of this variable.

Implement Comparable interface

global class MyWrapperclass implements Comparable
 {
    public String fName {get;set;
 }

public MyWrapperclass(String fullName) 
{    
   fName=fullName;
}

public MyWrapperclass() {
        }
}	

2. Override the compareTo method as below :

global Integer compareTo(Object objToCompare) {	 
 	if (objToCompare==NULL)
     		return 0;	
	 
	MyWrapperclass myObj = (MyWrapperclass) objToCompare;
 	String fn = myObj.fullName;
 	if (fn==NULL) 
     	fn='';

 	if (this.fullName==NULL)
     		return 0; 

 	return this.fullName.compareTo(fn);
    }

3. Sort your list :

 public void sortMyList() 
{
 	courseCatalogList = new List();
 	CourseCatalogWrapper obj1  = new CourseCatalogWrapper();
obj1.fName = ‘John’;
CourseCatalogWrapper obj2  = new CourseCatalogWrapper();
obj2.fName = ‘Aarav’;

CourseCatalogWrapper obj3  = new CourseCatalogWrapper();
obj3.fName = ‘Nick’;

            courseCatalogList.add(obj1);
courseCatalogList.add(obj2);
    	courseCatalogList.add(obj3);

            courseCatalogList.sort();
 }