/*
* Copyright 2014 - 2018 Rafael Winterhalter
*
* 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 net.bytebuddy.utility;
import java.util.
ArrayList;
import java.util.
Collections;
import java.util.
List;
/**
* Creates a list representation of two lists as a single, compound list.
*/
public class
CompoundList {
/**
* A compound list cannot be created.
*/
private
CompoundList() {
throw new
UnsupportedOperationException("This class is a utility class and not supposed to be instantiated");
}
/**
* Creates a list of a single element and another list.
*
* @param left The left element.
* @param right The right list.
* @param <S> The type of the list's elements.
* @return A compound list representing the element and the list.
*/
public static <S>
List<S>
of(S
left,
List<? extends S>
right) {
if (
right.
isEmpty()) {
return
Collections.
singletonList(
left);
} else {
List<S>
list = new
ArrayList<S>(1 +
right.
size());
list.
add(
left);
list.
addAll(
right);
return
list;
}
}
/**
* Creates a list of a list and an element.
*
* @param left The left left.
* @param right The right element.
* @param <S> The type of the list's elements.
* @return A compound list representing the element and the list.
*/
public static <S>
List<S>
of(
List<? extends S>
left, S
right) {
if (
left.
isEmpty()) {
return
Collections.
singletonList(
right);
} else {
List<S>
list = new
ArrayList<S>(
left.
size() + 1);
list.
addAll(
left);
list.
add(
right);
return
list;
}
}
/**
* Creates a list of a left and right list.
*
* @param left The left list.
* @param right The right list.
* @param <S> The type of the list's elements.
* @return A compound list representing the elements of both lists.
*/
public static <S>
List<S>
of(
List<? extends S>
left,
List<? extends S>
right) {
List<S>
list = new
ArrayList<S>(
left.
size() +
right.
size());
list.
addAll(
left);
list.
addAll(
right);
return
list;
}
/**
* Creates a list of a left, a middle and a right list.
*
* @param left The left list.
* @param middle The middle list.
* @param right The right list.
* @param <S> The type of the list's elements.
* @return A compound list representing the elements of all lists.
*/
public static <S>
List<S>
of(
List<? extends S>
left,
List<? extends S>
middle,
List<? extends S>
right) {
List<S>
list = new
ArrayList<S>(
left.
size() +
middle.
size() +
right.
size());
list.
addAll(
left);
list.
addAll(
middle);
list.
addAll(
right);
return
list;
}
}