Question

How to remove repeated elements from ArrayList in Java

Answer 1

import java.util.ArrayList;
import java.util.HashSet;
import java.util.Set;
 
public class MyClass {
    public static void main(String args[]) {
         
        ArrayList<String> al = new ArrayList<String>(); 
    
        al.add("java"); 
        al.add("c++"); 
        al.add("c"); 
        al.add("javascript"); 
        al.add("c#");  
        al.add("c");  
        al.add("c");  
        al.add("php"); 
        al.add("php"); 
        al.add("javascript"); 
        
        Set<String> set = new HashSet<>(al);
        
        al.clear();
        
        al.addAll(set);
 
        System.out.println(al);
    }
}
 
 
 
 
 
/*
run:
 
[c#, c++, java, c, php, javascript]
 
*/

 

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