| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| FastStack |
|
| 1.7;1.7 |
| 1 | //////////////////////////////////////////////////////////////////////////////// | |
| 2 | // checkstyle: Checks Java source code for adherence to a set of rules. | |
| 3 | // Copyright (C) 2001-2014 Oliver Burn | |
| 4 | // | |
| 5 | // This library is free software; you can redistribute it and/or | |
| 6 | // modify it under the terms of the GNU Lesser General Public | |
| 7 | // License as published by the Free Software Foundation; either | |
| 8 | // version 2.1 of the License, or (at your option) any later version. | |
| 9 | // | |
| 10 | // This library is distributed in the hope that it will be useful, | |
| 11 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | // Lesser General Public License for more details. | |
| 14 | // | |
| 15 | // You should have received a copy of the GNU Lesser General Public | |
| 16 | // License along with this library; if not, write to the Free Software | |
| 17 | // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | //////////////////////////////////////////////////////////////////////////////// | |
| 19 | package com.puppycrawl.tools.checkstyle.api; | |
| 20 | ||
| 21 | import com.google.common.collect.Lists; | |
| 22 | import java.util.Iterator; | |
| 23 | import java.util.List; | |
| 24 | ||
| 25 | /** | |
| 26 | * Simple implementation of a LIFO Stack that can be used instead of | |
| 27 | * {@link java.util.Vector} which is <tt>synchronized</tt>. | |
| 28 | * @author oliverb | |
| 29 | * @param <E> The type to hold. | |
| 30 | */ | |
| 31 | 897 | public class FastStack<E> implements Iterable<E> |
| 32 | { | |
| 33 | /** Hold the entries in the stack. */ | |
| 34 | 897 | private final List<E> mEntries = Lists.newArrayList(); |
| 35 | ||
| 36 | /** | |
| 37 | * Pushes the supplied element onto the stack. | |
| 38 | * @param aElement the element to push onto the stack. | |
| 39 | */ | |
| 40 | public void push(E aElement) | |
| 41 | { | |
| 42 | 13576 | mEntries.add(aElement); |
| 43 | 13576 | } |
| 44 | ||
| 45 | /** | |
| 46 | * Returns whether the stack is empty. | |
| 47 | * @return whether the stack is empty. | |
| 48 | */ | |
| 49 | public boolean isEmpty() | |
| 50 | { | |
| 51 | 104 | return mEntries.isEmpty(); |
| 52 | } | |
| 53 | ||
| 54 | /** | |
| 55 | * Returns the number of entries in the stack. | |
| 56 | * @return the number of entries in the stack. | |
| 57 | */ | |
| 58 | public int size() | |
| 59 | { | |
| 60 | 297 | return mEntries.size(); |
| 61 | } | |
| 62 | ||
| 63 | /** | |
| 64 | * Returns the entry at the top of the stack without removing it. | |
| 65 | * @return the top entry | |
| 66 | * @throws IllegalStateException if the stack is empty. | |
| 67 | */ | |
| 68 | public E peek() | |
| 69 | { | |
| 70 | 2097 | if (mEntries.isEmpty()) { |
| 71 | 1 | throw new IllegalStateException("FastStack is empty"); |
| 72 | } | |
| 73 | 2096 | return mEntries.get(mEntries.size() - 1); |
| 74 | } | |
| 75 | ||
| 76 | /** | |
| 77 | * Returns the entry at the top of the stack by removing it. | |
| 78 | * @return the top entry | |
| 79 | * @throws IllegalStateException if the stack is empty. | |
| 80 | */ | |
| 81 | public E pop() | |
| 82 | { | |
| 83 | 13493 | if (mEntries.isEmpty()) { |
| 84 | 1 | throw new IllegalStateException("FastStack is empty"); |
| 85 | } | |
| 86 | 13492 | return mEntries.remove(mEntries.size() - 1); |
| 87 | } | |
| 88 | ||
| 89 | /** | |
| 90 | * Return the element at the specified index. It does not remove the | |
| 91 | * element from the stack. | |
| 92 | * @param aIndex the index to return | |
| 93 | * @return the element at the index | |
| 94 | * @throws IllegalArgumentException if index out of range | |
| 95 | */ | |
| 96 | public E peek(int aIndex) | |
| 97 | { | |
| 98 | 544 | if ((aIndex < 0) || (aIndex >= mEntries.size())) { |
| 99 | 0 | throw new IllegalArgumentException("index out of range."); |
| 100 | } | |
| 101 | 544 | return mEntries.get(aIndex); |
| 102 | } | |
| 103 | ||
| 104 | /** | |
| 105 | * Returns if the stack contains the specified element. | |
| 106 | * @param aElement the element to find | |
| 107 | * @return whether the stack contains the entry | |
| 108 | */ | |
| 109 | public boolean contains(E aElement) | |
| 110 | { | |
| 111 | 9 | return mEntries.contains(aElement); |
| 112 | } | |
| 113 | ||
| 114 | /** | |
| 115 | * Clears the stack. | |
| 116 | */ | |
| 117 | public void clear() | |
| 118 | { | |
| 119 | 79 | mEntries.clear(); |
| 120 | 79 | } |
| 121 | ||
| 122 | /** | |
| 123 | * Returns an iterator that goes from the oldest element to the newest. | |
| 124 | * @return an iterator | |
| 125 | */ | |
| 126 | public Iterator<E> iterator() | |
| 127 | { | |
| 128 | 10947 | return mEntries.iterator(); |
| 129 | } | |
| 130 | ||
| 131 | /** | |
| 132 | * Factory method to create a new instance. | |
| 133 | * @param <T> the type of elements to hold in the stack. | |
| 134 | * @return a new instance of {@link FastStack} | |
| 135 | */ | |
| 136 | public static <T> FastStack<T> newInstance() | |
| 137 | { | |
| 138 | 891 | return new FastStack<T>(); |
| 139 | } | |
| 140 | } |