Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

import java.util.Comparator;

public class Main {
    /**
     * Exactly the same as {@link Comparator#naturalOrder()}, but can be used to compare objects
     * whose type is unknown. The comparator will throw a {@link ClassCastException} if presented
     * with arguments that aren't mutually {@linkplain Comparable comparable}. 
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public static Comparator<Object> naturalOrder() {
        // Use raw type to eliminate the lower bound of Comparable on argument type.
        Comparator ret = Comparator.naturalOrder();
        // This implicitly does an unchecked cast. In this case, it's okay, because we explicitly
        // document this comparator as throwing ClassCastException when given objects that are not
        // Comparable.
        // NB: We do not have our own naturalOrder Comparator, to avoid these type gymnastics and
        // compiler warnings, because it is very convenient for code to test whether a given
        // comparator is a natural ordering:
        //  comparator == Comparator.naturalOrder()
        // We preserve that ability by using the same comparator and doing casts to make javac let us.
        return ret;
    }
}