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/*
* Copyright (c) 2013 Google Inc.
*
* 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.
*/
package com.google.api.client.util;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
/**
* Static utility methods pertaining to {@link List} instances.
*
* NOTE: this is a copy of a subset of Guava's {@link com.google.common.collect.Lists}. The
* implementation must match as closely as possible to Guava's implementation.
*
* @since 1.14
* @author Yaniv Inbar
*/
public final class Lists {
/** Returns a new mutable, empty {@code ArrayList} instance. */
public static ArrayList newArrayList() {
return new ArrayList();
}
/**
* Creates an {@code ArrayList} instance backed by an array of the exact size specified;
* equivalent to {@link ArrayList#ArrayList(int)}.
*
* @param initialArraySize the exact size of the initial backing array for the returned array list
* ({@code ArrayList} documentation calls this value the "capacity")
* @return a new, empty {@code ArrayList} which is guaranteed not to resize itself unless its size
* reaches {@code initialArraySize + 1}
* @throws IllegalArgumentException if {@code initialArraySize} is negative
*/
public static ArrayList newArrayListWithCapacity(int initialArraySize) {
return new ArrayList(initialArraySize);
}
/**
* Returns a new mutable {@code ArrayList} instance containing the given elements.
*
* @param elements the elements that the list should contain, in order
* @return a new {@code ArrayList} containing those elements
*/
public static ArrayList newArrayList(Iterable elements) {
return (elements instanceof Collection)
? new ArrayList(Collections2.cast(elements))
: newArrayList(elements.iterator());
}
/**
* Returns a new mutable {@code ArrayList} instance containing the given elements.
*
* @param elements the elements that the list should contain, in order
* @return a new {@code ArrayList} containing those elements
*/
public static ArrayList newArrayList(Iterator elements) {
ArrayList list = newArrayList();
while (elements.hasNext()) {
list.add(elements.next());
}
return list;
}
private Lists() {}
}