Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 * 
 *  http://www.apache.org/licenses/LICENSE-2.0
 * 
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */

import java.util.Collections;

import java.util.HashSet;

import java.util.Set;

public class Main {
    /**
     * Returns a minimal Set containing the elements passed in.  There is no guarantee that the
     * returned set is mutable or immutable.
     * @param <T>
     * @param a The elements to add to the Set
     * @return A set containing the elements passed in.
     * @see #asUnmodifiableSet
     */
    public static <T> Set<T> asSet(T... a) {
        return _asSet(a, false);
    }

    private static <T> Set<T> _asSet(T[] a, boolean makeImmutable) {
        int count = (a != null) ? a.length : 0;

        Set<T> outSet;

        if (count == 0) {
            outSet = Collections.emptySet();
        } else {
            if (count == 1) {
                outSet = Collections.singleton(a[0]);
            } else {
                // make the initial size big enough that we don't have to rehash to fit the array, for
                // the .75 load factor we pass in
                int initialSize = (int) Math.ceil(count / .75d);

                outSet = new HashSet<T>(initialSize, .75f);

                for (int i = 0; i < count; i++) {
                    outSet.add(a[i]);
                }

                if (makeImmutable) {
                    outSet = Collections.unmodifiableSet(outSet);
                }
            }
        }

        return outSet;
    }
}