Main.java Source code

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Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Hibernate Validator, declare and validate application constraints
 *
 * License: Apache License, Version 2.0
 * See the license.txt file in the root directory or <http://www.apache.org/licenses/LICENSE-2.0>.
 */

import java.util.Collection;

import java.util.HashSet;

public class Main {
    public static <T> HashSet<T> newHashSet() {
        return new HashSet<T>();
    }

    public static <T> HashSet<T> newHashSet(int size) {
        return new HashSet<T>(getInitialCapacityFromExpectedSize(size));
    }

    public static <T> HashSet<T> newHashSet(Collection<? extends T> c) {
        return new HashSet<T>(c);
    }

    public static <T> HashSet<T> newHashSet(Iterable<? extends T> iterable) {
        HashSet<T> set = newHashSet();
        for (T t : iterable) {
            set.add(t);
        }
        return set;
    }

    /**
     * As the default loadFactor is of 0.75, we need to calculate the initial capacity from the expected size to avoid
     * resizing the collection when we populate the collection with all the initial elements. We use a calculation
     * similar to what is done in {@link HashMap#putAll(Map)}.
     *
     * @param expectedSize the expected size of the collection
     * @return the initial capacity of the collection
     */
    private static int getInitialCapacityFromExpectedSize(int expectedSize) {
        if (expectedSize < 3) {
            return expectedSize + 1;
        }
        return (int) ((float) expectedSize / 0.75f + 1.0f);
    }
}