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Java - Comparing enums based on Enum.compareTo() method

Java 

java.lang.Enum implements Comparable interface. Its compareTo method compares the elements based on their ordinals.
Enum#compareTo method returns self.ordinal - other.ordinal.
The elements being compared must be from the same enum class. 

package com.logicbig.example;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class EnumCompareToExample {
    enum MyEnum {
        E, B, A, C, D
    }

    public static void main(String[] args) {
        int i = MyEnum.A.compareTo(MyEnum.E);
        System.out.println(i);

        i = MyEnum.B.compareTo(MyEnum.E);
        System.out.println(i);

        List<MyEnum> list = Arrays.asList(MyEnum.A, MyEnum.B,
                MyEnum.C, MyEnum.D, MyEnum.E);
        Collections.sort(list);
        System.out.println(list);
    }
}

Output

2
1
[E, B, A, C, D]

See Also