/** Copyright by Barry G. Becker, 2000-2011. Licensed under MIT License: http://www.opensource.org/licenses/MIT */
package com.barrybecker4.game.twoplayer.common.search.tree;
import com.barrybecker4.game.twoplayer.common.TwoPlayerMove;
import javax.swing.tree.DefaultMutableTreeNode;
import java.awt.*;
import java.util.Enumeration;
import java.util.List;
/**
* Represents a move/node in the game tree.
* Each SearchTreeNode contains a Move as its userObject.
* When showing the game tree graphically, these variables can take a lot of space
* since they are in every node in the tree. Still it is better to have them here than
* in the move structure so that when we are not in debug mode the space is not used.
*
* @author Barry Becker
*/
public class SearchTreeNode extends DefaultMutableTreeNode {
private static final long serialVersionUID = 1L;
public NodeAttributes attributes;
/**
* Used to layout the tree. Roughly based on the num descendants.
* initialized by GameTreeViewer.
*/
private int spaceAllocation_ = 0;
/**
* location in the board viewer
*/
private Point position_;
/**
* Default Constructor
* @param move a twoplayer board move.
*/
public SearchTreeNode(TwoPlayerMove move) {
setUserObject(move);
this.attributes = new NodeAttributes();
}
/**
* Default Constructor
* @param move a twoplayer board move.
* @param attributes set of name value pairs describing the node.
*/
public SearchTreeNode(TwoPlayerMove move, final NodeAttributes attributes) {
setUserObject(move);
this.attributes = attributes;
}
public TwoPlayerMove[] getChildMoves() {
if (children == null) return null;
TwoPlayerMove[] moves = new TwoPlayerMove[children.size()];
Enumeration enumeration = children();
int i = 0;
while (enumeration.hasMoreElements()) {
SearchTreeNode node = (SearchTreeNode)enumeration.nextElement();
moves[i++] = (TwoPlayerMove)node.getUserObject();
}
return moves;
}
/**
* Show nodes corresponding to pruned branches in the game tree (if one is used).
*
* @param list list of moves that resulted in pruned branches.
* @param i th child.
* @param attributes list of name values to show.
*/
public void addPrunedChildNodes( List list, int i, NodeAttributes attributes) {
int index = i;
while ( !list.isEmpty() ) {
TwoPlayerMove theMove = (TwoPlayerMove) (list.remove(0));
SearchTreeNode child = new SearchTreeNode( theMove, attributes );
this.insert( child, index );
index++;
}
}
/**
*
* @return the move that the computer expects will be played next
*/
public SearchTreeNode getExpectedNextNode() {
if (children == null) return null;
Enumeration enumeration = children();
while (enumeration.hasMoreElements()) {
SearchTreeNode node = (SearchTreeNode)enumeration.nextElement();
TwoPlayerMove m = (TwoPlayerMove)node.getUserObject();
if (m.isSelected())
return node;
}
return null;
}
/**
* One of our existing children bust be the next node.
* It must never be null, but it may not be there yet because they are added in a different thread
* So we block until there.
* @param move the move whose child moves we will search.
* @return the next child node to use as parent. Must never be null.
*/
public SearchTreeNode findChild(TwoPlayerMove move) {
Enumeration enumeration = this.children();
while (enumeration.hasMoreElements()) {
SearchTreeNode node = (SearchTreeNode)enumeration.nextElement();
if (move.equals(node.getUserObject())) {
return node;
}
}
return null;
}
/**
* Serialize all the children.
* @return children represented in string form
*/
private String childrenAsString() {
StringBuilder bld = new StringBuilder();
Enumeration enumeration = this.children();
while (enumeration.hasMoreElements()) {
SearchTreeNode node = (SearchTreeNode)enumeration.nextElement();
bld.append(node);
}
return bld.toString();
}
public boolean isPruned() {
return attributes.pruned;
}
@Override
public String toString () {
Object m = getUserObject();
if (m == null) return null;
StringBuilder s = new StringBuilder(m.toString());
s.append(attributes.toString());
return s.toString();
}
public int getSpaceAllocation() {
return spaceAllocation_;
}
public void setSpaceAllocation(int spaceAllocation) {
this.spaceAllocation_ = spaceAllocation;
}
public Point getPosition() {
return position_;
}
public void setLocation(int x, int y) {
position_ = new Point(x, y);
}
}