Here you can find the source of toArray(Collection
static public String[] toArray(Collection<String> col)
//package com.java2s; /**/*from ww w . ja v a 2 s. co m*/ * Copyright 2014, Emory University * * 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; public class Main { static public String[] toArray(Collection<String> col) { String[] array = new String[col.size()]; col.toArray(array); return array; } }