Main.java Source code

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Here is the source code for Main.java

Source

//package com.java2s;
//License from project: Apache License 

import java.util.Collection;

import java.util.Map;

public class Main {
    /**
     * Find the common element type of the given Collection, if any.
     * @param collection the Collection to check
     * @return the common element type, or <code>null</code> if no clear
     * common type has been found (or the collection was empty)
     */
    public static Class<?> findCommonElementType(Collection collection) {
        if (isEmpty(collection)) {
            return null;
        }
        Class<?> candidate = null;
        for (Object val : collection) {
            if (val != null) {
                if (candidate == null) {
                    candidate = val.getClass();
                } else if (candidate != val.getClass()) {
                    return null;
                }
            }
        }
        return candidate;
    }

    public static boolean isEmpty(Collection<?> collection) {
        return (collection == null || collection.isEmpty());
    }

    /**
     * Return <code>true</code> if the supplied Map is <code>null</code>
     * or empty. Otherwise, return <code>false</code>.
     * @param map the Map to check
     * @return whether the given Map is empty
     */
    public static boolean isEmpty(Map map) {
        return (map == null || map.isEmpty());
    }
}