[Solved] Sorting ArrayList without sorting the index in java

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Besides the Map option, you can consider using some sort of Key value pair and, storing that in your array and sort your array based on the values.

See this for potential key value pairs, or make your own.

An example:

package com.example;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class KeyValue {

    private int key;
    private Integer value;

    public KeyValue(int i, Integer j) {
        key  = i;
        value = j;
    }

    public static void main(String[] args) {

        List<KeyValue> arr = new ArrayList<KeyValue>();
        arr.add(new KeyValue(1, 100));
        arr.add(new KeyValue(2, 50));
        arr.add(new KeyValue(3, 10));
        Collections.sort(arr, new Comparator<KeyValue>(){

            @Override
            public int compare(KeyValue arg0, KeyValue arg1) {
                return Integer.compare(arg0.getValue(), arg1.getValue());
            }

        });
        for (KeyValue kv : arr){
            System.out.println(kv);
        }
    }

    public int getKey() {
        return key;
    }

    public void setKey(int key) {
        this.key = key;
    }

    public Integer getValue() {
        return value;
    }

    public void setValue(Integer value) {
        this.value = value;
    }

    @Override
    public String toString(){
        return "("+key+","+value.toString()+")";                
    }

}

solved Sorting ArrayList without sorting the index in java