Java tutorial
//package com.java2s; /* * Copyright 2004-2014 the Seasar Foundation and the Others. * * Licensed 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.Collection; import java.util.HashSet; public class Main { public static <ELEMENT> HashSet<ELEMENT> newHashSet() { return new HashSet<ELEMENT>(); } public static <ELEMENT> HashSet<ELEMENT> newHashSet(Collection<ELEMENT> elements) { final HashSet<ELEMENT> set = newHashSetSized(elements.size()); set.addAll(elements); return set; } public static <ELEMENT> HashSet<ELEMENT> newHashSet(ELEMENT... elements) { final HashSet<ELEMENT> set = newHashSetSized(elements.length); for (ELEMENT element : elements) { set.add(element); } return set; } public static <ELEMENT> HashSet<ELEMENT> newHashSetSized(int size) { return new HashSet<ELEMENT>(size); } }