I'm sure there is a simple answer to this because I think I have used or heard of it previously but can't seem to find it, possibly because Google doesn't understand English. Basically I need something similar or the same as an array that does not allow duplicate values (in Java).
Example: int[] example = {1,2,2,3,4,4}
would be {1,2,3,4}
Hopefully this is clear enough for a human to understand even if Google couldn't.
You should use a Set implementation. And also an array in Java cannot behave like a set, but with a Set implementation like HashSet it is possible to manage the uniqueness of the elements within your collection.
Set<Integer> such as LinkedHashSet<Integer> or TreeSet<Integer>
You can use HashSet.
For integers it will work fine. But later if you plan to store Objects, you should override hashCode() and equals() method. Because HashSet internally uses equals() and hashcode() to check for equality.
Try using Set implementations
for example :
public static void main(String[] args) {
Set<Integer> numbers = new HashSet<>();
numbers.add(3);
numbers.add(5);
numbers.add(5);
numbers.add(5);
numbers.add(6);
numbers.add(12);
System.out.println(numbers);
}
will produce:
[3, 5, 6, 12]
import java.util.HashSet;
import java.util.Set;
public static void main(String[] args) {
Set<Integer> numbers = new HashSet<Integer>();
numbers.add(3);
numbers.add(5);
numbers.add(5);
numbers.add(5);
numbers.add(6);
numbers.add(12);
System.out.println(numbers);
}
Take this.you can get what you want to get.
Try this code for removing duplicates using Hashset
public static Integer[] removeDuplicateUsingSet(Integer[] example) {
List<Integer> inputList = Arrays.asList(example);
Set<Integer> inputSet = new HashSet<Integer>(inputList);
Integer[] ints = new Integer[inputSet.size()];
int index = 0;
for (Integer i : inputSet) {
ints[index++] = i;
}
return ints;
}
public static void main(String[] args) {
Integer[] example = { 1, 2, 2, 3, 4, 4 };
example = removeDuplicateUsingSet(example);
for(int i = 0 ;i < example.length;i++){
System.out.println(example[i]);
}
}
If can Use Hash Set while adding a element it won't allow Duplicate value or else u can use like this:
import java.util.ArrayList;
import java.util.Arrays;
public class NotDuplicateArray {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Integer[] Value={1,2,2,3,3,4,5,6,6};
ArrayList<Integer> Check=new ArrayList<Integer>();
int count=0;
int x = 1;
for(int i=0;i<Value.length;i++){
if(Check!=null){
if(!Check.contains(Value[i])){
Check.add(Value[i]);
}
}else{
Check.add(Value[i]);
}
}
for(int v:Check){
System.out.println(v);
}
}
}
