src/net/pterodactylus/util/data/NodeImpl.java

   1
   2 package net.pterodactylus.util.data;
   3
   4 import java.util.ArrayList;
   5 import java.util.Iterator;
   6 import java.util.List;
   7
   8 /**
   9  * Implementation of the {@link Node} interface.
  10  *
  11  * @author David ‘Bombe’ Roden &lt;bombe@freenetproject.org&gt;
  12  * @param <E>
  13  *            The type of the element to store
  14  */
  15 class NodeImpl<E> implements Node<E> {
  16
  17         /** The parent node of this node. */
  18         private final Node<E> parentNode;
  19
  20         /** The element contained in this node. */
  21         private final E element;
  22
  23         /** The child nodes of this node. */
  24         private final List<Node<E>> children = new ArrayList<Node<E>>();
  25
  26         /**
  27          * Creates a new root node.
  28          */
  29         NodeImpl() {
  30                 this.parentNode = null;
  31                 this.element = null;
  32         }
  33
  34         /**
  35          * Creates a new node with the given parent and element.
  36          *
  37          * @param parentNode
  38          *            The parent of this node
  39          * @param element
  40          *            The element of this node
  41          */
  42         NodeImpl(Node<E> parentNode, E element) {
  43                 if ((parentNode == null) || (element == null)) {
  44                         throw new NullPointerException("null is not allowed as parent or element");
  45                 }
  46                 this.parentNode = parentNode;
  47                 this.element = element;
  48         }
  49
  50         /**
  51          * {@inheritDoc}
  52          */
  53         public Node<E> getParent() {
  54                 return parentNode;
  55         }
  56
  57         /**
  58          * {@inheritDoc}
  59          */
  60         public E getElement() {
  61                 return element;
  62         }
  63
  64         /**
  65          * {@inheritDoc}
  66          */
  67         public Node<E> addChild(E child) {
  68                 Node<E> childNode = new NodeImpl<E>(this, child);
  69                 children.add(childNode);
  70                 return childNode;
  71         }
  72
  73         /**
  74          * {@inheritDoc}
  75          */
  76         public int size() {
  77                 return children.size();
  78         }
  79
  80         /**
  81          * {@inheritDoc}
  82          */
  83         public Node<E> getChild(int childIndex) {
  84                 return children.get(childIndex);
  85         }
  86
  87         /**
  88          * {@inheritDoc}
  89          */
  90         public boolean hasChildNode(Node<E> childNode) {
  91                 return children.contains(childNode);
  92         }
  93
  94         /**
  95          * {@inheritDoc}
  96          */
  97         public int getIndexOfChild(Node<E> childNode) {
  98                 int childIndex = 0;
  99                 for (Node<E> node: children) {
 100                         if (node.equals(childNode)) {
 101                                 return childIndex;
 102                         }
 103                         childIndex++;
 104                 }
 105                 return -1;
 106         }
 107
 108         /**
 109          * {@inheritDoc}
 110          */
 111         public int getIndexOfChild(E element) {
 112                 int childIndex = 0;
 113                 for (Node<E> node: children) {
 114                         if (node.getElement().equals(element)) {
 115                                 return childIndex;
 116                         }
 117                         childIndex++;
 118                 }
 119                 return -1;
 120         }
 121
 122         /**
 123          * {@inheritDoc}
 124          */
 125         public void removeChild(Node<E> childNode) {
 126                 children.remove(childNode);
 127         }
 128
 129         /**
 130          * {@inheritDoc}
 131          */
 132         public void removeChild(E child) {
 133                 for (Node<E> childNode: children) {
 134                         if (child.equals(childNode.getElement())) {
 135                                 children.remove(childNode);
 136                                 break;
 137                         }
 138                 }
 139         }
 140
 141         /**
 142          * {@inheritDoc}
 143          */
 144         public void removeChild(int childIndex) {
 145                 children.remove(childIndex);
 146         }
 147
 148         /**
 149          * {@inheritDoc}
 150          */
 151         public Iterator<Node<E>> iterator() {
 152                 return children.iterator();
 153         }
 154
 155         /**
 156          * {@inheritDoc}
 157          */
 158         public Node<E> findChild(E element) {
 159                 for (Node<E> childNode: children) {
 160                         Node<E> wantedNode = childNode.findChild(element);
 161                         if (wantedNode != null) {
 162                                 return wantedNode;
 163                         }
 164                 }
 165                 if (this.element.equals(element)) {
 166                         return this;
 167                 }
 168                 return null;
 169         }
 170
 171 }