src/main/java/net/pterodactylus/sone/text/PartContainer.java

   1 /*
   2  * Sone - PartContainer.java - Copyright © 2010 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.sone.text;
  19
  20 import java.util.ArrayDeque;
  21 import java.util.ArrayList;
  22 import java.util.Deque;
  23 import java.util.Iterator;
  24 import java.util.List;
  25 import java.util.NoSuchElementException;
  26
  27 /**
  28  * Part implementation that can contain an arbitrary amount of other parts.
  29  * Parts are added using the {@link #add(Part)} method and will be rendered in
  30  * the order they are added.
  31  *
  32  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  33  */
  34 public class PartContainer implements Part, Iterable<Part> {
  35
  36         /** The parts to render. */
  37         private final List<Part> parts = new ArrayList<Part>();
  38
  39         //
  40         // ACCESSORS
  41         //
  42
  43         /**
  44          * Adds a part to render.
  45          *
  46          * @param part
  47          *            The part to add
  48          */
  49         public void add(Part part) {
  50                 parts.add(part);
  51         }
  52
  53         /**
  54          * Returns the part at the given index.
  55          *
  56          * @param index
  57          *            The index of the part
  58          * @return The part
  59          */
  60         public Part getPart(int index) {
  61                 return parts.get(index);
  62         }
  63
  64         /**
  65          * Removes the part at the given index.
  66          *
  67          * @param index
  68          *            The index of the part to remove
  69          */
  70         public void removePart(int index) {
  71                 parts.remove(index);
  72         }
  73
  74         /**
  75          * Returns the number of parts.
  76          *
  77          * @return The number of parts
  78          */
  79         public int size() {
  80                 return parts.size();
  81         }
  82
  83         //
  84         // ITERABLE METHODS
  85         //
  86
  87         /**
  88          * {@inheritDoc}
  89          */
  90         @Override
  91         @SuppressWarnings("synthetic-access")
  92         public Iterator<Part> iterator() {
  93                 return new Iterator<Part>() {
  94
  95                         private Deque<Iterator<Part>> partStack = new ArrayDeque<Iterator<Part>>();
  96                         private Part nextPart;
  97                         private boolean foundNextPart;
  98                         private boolean noNextPart;
  99
 100                         {
 101                                 partStack.push(parts.iterator());
 102                         }
 103
 104                         private void findNext() {
 105                                 if (foundNextPart) {
 106                                         return;
 107                                 }
 108                                 noNextPart = true;
 109                                 while (!partStack.isEmpty()) {
 110                                         Iterator<Part> parts = partStack.pop();
 111                                         if (parts.hasNext()) {
 112                                                 nextPart = parts.next();
 113                                                 partStack.push(parts);
 114                                                 if (nextPart instanceof PartContainer) {
 115                                                         partStack.push(((PartContainer) nextPart).iterator());
 116                                                 } else {
 117                                                         noNextPart = false;
 118                                                         break;
 119                                                 }
 120                                         }
 121                                 }
 122                                 foundNextPart = true;
 123                         }
 124
 125                         @Override
 126                         public boolean hasNext() {
 127                                 findNext();
 128                                 return !noNextPart;
 129                         }
 130
 131                         @Override
 132                         public Part next() {
 133                                 findNext();
 134                                 if (noNextPart) {
 135                                         throw new NoSuchElementException();
 136                                 }
 137                                 foundNextPart = false;
 138                                 return nextPart;
 139                         }
 140
 141                         @Override
 142                         public void remove() {
 143                                 /* ignore. */
 144                         }
 145
 146                 };
 147         }
 148
 149 }