基因算法bug（程序不大长，分数大大有）

Question

简单的解释一下我的程序。
gene.java 基因类：其中的getgene（）方法表示生成一个染色体（二维数组gene[i][j]），其中第一个维度i你可以不用管他，我都设为1，表示只有一代染色体。也就是说，这个2维数组目前只是一个一维的向量。
main.java 类： 程序入口
maze.java 类：迷宫类。定义迷宫不能走的地方，isObstacle（）表示那个地方是障碍，outOfMaze()就是超出了迷宫的范围。
mazeSolver.java 类： 解决方法类，也是算法的核心。解释一下 move() 因为gene[][]的值是0，1，2，3这4个数中的随机一个。 如果是0，我定义它为向上，也就是纵坐标＋1。后面类似。
目前的问题是，第一个值运行的很好，如果nextPoint是障碍或者超出迷宫，currentPoint会保持不变，然后计算下一个nextPoint，直到nextPoint为一个合法的值，才会执行currentPoint = nextPoint
但是之后就乱套了，不管是不是障碍，不管是不是超出迷宫，程序都会执行 currentPoint = nextPoint， 不知道为什么。
gene.java/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package gam;import java.util.Random;/**
 *
 * @author panyunpeng
 */
public class Gene {    /**
     * 
     * @param x number of chromosome
     * @return one generation of chromosome
     */
    Maze maze;    public Gene(Maze maze) {
        this.maze = maze;
    }    /**
     * 
     * @param x max number of chromosomes
     * @return
     */
    
    /*
     * generate gene
     */
    public int[][] getGene(int x) {        int maxNumberOfChromosome = x;//你可以不用管他，目前我都设为1
        int gene[][] = new int[maxNumberOfChromosome][maze.width * maze.height];//基因的长度是迷宫的长＊宽
        int i, j;
        Random k = new Random();
        for (i = 0; i < maxNumberOfChromosome; i++) {//i number of chromosomes
            for (j = 0; j < maze.width * maze.height; j++) { //j number of alleles
                int u = k.nextInt(4);//random from 0 to 3(int)
                gene[i][j] = u;
            }
        }
        return gene;
    }
}main.java/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package gam;import java.awt.Point;/**
 *
 * @author panyunpeng
 */
public class Main {
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {        Point startPoint = new Point(0,0);
        Point endPoint = new Point(12,12);
        Maze myMaze = new Maze(13,13);
        Gene myGene = new Gene(myMaze);
        MazeSolver ms = new MazeSolver(myGene, myMaze);
        ms.findWayOut(startPoint, endPoint);
        System.out.println("MaxDistance:" + new Point(0,0).distance(new Point(12,12)));//忽略它    }
}Maze.java/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package gam;import java.awt.Point;/**
 *
 * @author panyunpeng
 */
public class Main {
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {        Point startPoint = new Point(0,0);
        Point endPoint = new Point(12,12);
        Maze myMaze = new Maze(13,13);
        Gene myGene = new Gene(myMaze);
        MazeSolver ms = new MazeSolver(myGene, myMaze);
        ms.findWayOut(startPoint, endPoint);
        System.out.println("MaxDistance:" + new Point(0,0).distance(new Point(12,12)));//忽略它    }
}
MazeSolver.java/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package gam;import java.awt.Point;/**
 *
 * @author panyunpeng
 */
public class MazeSolver {    Gene myGene;
    Maze myMaze;
    double fitness;//适应度，你可以忽略它
    Point currentPoint = new Point(0,0);
    Point nextPoint = new Point(0,0);
    int numberOfChromosome = 1;
    int currentChromosome;//忽略
    int currentAllele;//就是基因的第二维。
    int[][] gene;    public MazeSolver(Gene g, Maze m) {
        this.myGene = g;
        this.myMaze = m;
    }    public void findWayOut(Point startPoint, Point endPoint) {
//        currentPoint = new Point(0,0);
//        nextPoint = new Point(0,0);
        System.out.println("Start from here: "+currentPoint);
        System.out.println("Initial next point: "+nextPoint);
        gene = myGene.getGene(numberOfChromosome);
        myMaze.init();
        for (int i = 0; i < numberOfChromosome; i++) {
            currentChromosome = i;
            for (int j = 0; j < myMaze.height * myMaze.width; j++) {
                currentAllele = j;
                this.move();
                if(myMaze.isObstacle(nextPoint)){
                 System.out.println("Error:Obstacle!" + nextPoint + "We still at the point: " +currentPoint);
                }
                else if(myMaze.outOfMaze(nextPoint)){
                 System.out.println("Error:Out of maze!" + nextPoint + "We still at the point: " + currentPoint);
                }
                else{
                 System.out.println("Moved!");
                 currentPoint = nextPoint;
                 System.out.println("Now we are at the new point: " + currentPoint);
                }
            }
        }
    }    public void move() {        int i = currentChromosome;
        int j = currentAllele;
        if (gene[i][j] == 0) { //up
            nextPoint.x = currentPoint.x;
            nextPoint.y = currentPoint.y + 1;
            System.out.println("Next point calculated:" +nextPoint+"Current chromosome: " + currentChromosome+ "Current point:"+currentPoint);
        } else if (gene[i][j] == 1) {//down
            nextPoint.x = currentPoint.x;
            nextPoint.y = currentPoint.y - 1;
            System.out.println("Next point calculated"+nextPoint+"Current chromosome: " + currentChromosome+ "Current point:"+currentPoint);
        } else if (gene[i][j] == 2) {//left
            nextPoint.x = currentPoint.x - 1;
            nextPoint.y = currentPoint.y;
            System.out.println("Next point calculated"+nextPoint+"Current chromosome: " + currentChromosome+ "Current point:"+currentPoint);
        } else //right
        {
            nextPoint.x = currentPoint.x + 1;
            nextPoint.y = currentPoint.y;
            System.out.println("Next point calculated"+nextPoint+"Current chromosome: " + currentChromosome+ "Current point:"+currentPoint);
        }    }
}

Answer 1

你看下你发的Maze.java就知道了

Answer 2

你发的Maze.java
里面是Main.java的内容

Answer 3

对不起各位，我把maze.java再发一次。Maze.java
----------package gam;import java.awt.Point;
import java.util.ArrayList;
import java.util.List;public class Maze { int height;
int width; public Maze(int height, int width) {
this.height = height;
this.width = width;
} List<Point> obstacleList = new ArrayList<Point>(); /*
 * Discribe a maze
 */
public void init() {
obstacleList.add(new Point(0, 7));
obstacleList.add(new Point(1, 1));
obstacleList.add(new Point(1, 3));
obstacleList.add(new Point(1, 4));
obstacleList.add(new Point(1, 5));
obstacleList.add(new Point(1, 7));
obstacleList.add(new Point(1, 9));
obstacleList.add(new Point(1, 10));
obstacleList.add(new Point(1, 11));
obstacleList.add(new Point(2, 1));
obstacleList.add(new Point(2, 7));
obstacleList.add(new Point(2, 9));
obstacleList.add(new Point(3, 1));
obstacleList.add(new Point(3, 4));
obstacleList.add(new Point(3, 5));
obstacleList.add(new Point(3, 7));
obstacleList.add(new Point(3, 9));
obstacleList.add(new Point(3, 11));
obstacleList.add(new Point(4, 5));
obstacleList.add(new Point(4, 9));
obstacleList.add(new Point(4, 11));
obstacleList.add(new Point(5, 1));
obstacleList.add(new Point(5, 2));
obstacleList.add(new Point(5, 3));
obstacleList.add(new Point(5, 5));
obstacleList.add(new Point(5, 6));
obstacleList.add(new Point(5, 7));
obstacleList.add(new Point(5, 8));
obstacleList.add(new Point(5, 9));
obstacleList.add(new Point(5, 11));
obstacleList.add(new Point(6, 1));
obstacleList.add(new Point(6, 7));
obstacleList.add(new Point(7, 1));
obstacleList.add(new Point(7, 3));
obstacleList.add(new Point(7, 4));
obstacleList.add(new Point(7, 5));
obstacleList.add(new Point(7, 6));
obstacleList.add(new Point(7, 7));
obstacleList.add(new Point(7, 9));
obstacleList.add(new Point(7, 10));
obstacleList.add(new Point(7, 11));
obstacleList.add(new Point(7, 12));
obstacleList.add(new Point(8, 1));
obstacleList.add(new Point(8, 7));
obstacleList.add(new Point(9, 1));
obstacleList.add(new Point(9, 2));
obstacleList.add(new Point(9, 3));
obstacleList.add(new Point(9, 4));
obstacleList.add(new Point(9, 5));
obstacleList.add(new Point(9, 7));
obstacleList.add(new Point(9, 9));
obstacleList.add(new Point(9, 10));
obstacleList.add(new Point(9, 11));
obstacleList.add(new Point(10, 1));
obstacleList.add(new Point(10, 5));
obstacleList.add(new Point(10, 9));
obstacleList.add(new Point(11, 1));
obstacleList.add(new Point(11, 3));
obstacleList.add(new Point(11, 5));
obstacleList.add(new Point(11, 6));
obstacleList.add(new Point(11, 7));
obstacleList.add(new Point(11, 8));
obstacleList.add(new Point(11, 9));
obstacleList.add(new Point(11, 11));
obstacleList.add(new Point(11, 12));
obstacleList.add(new Point(12, 3));
obstacleList.add(new Point(12, 5)); } public boolean isObstacle(Point P) {
return obstacleList.contains(P);
} public boolean outOfMaze(Point p) {
if ((p.x < 0) || (p.y < 0)) {
return true;
} 
else if((p.x > 12) || (p.y > 12)) {
return true;
}
else return false;
}}

Answer 4

问题关键：
MazeSolver.java中
这一句：
currentPoint = nextPoint;
所以在一次成功的moved之后，
你的currentPoint和nextPoint的引用变成了同一个对象你之后做move()方法的时候
nextPoint.x = currentPoint.x;
nextPoint.y = currentPoint.y - 1;
这样的语句，实际上就是改变了currentPoint本身的值了
在move()的时候，你就已经让currentPoint超出迷宫了所以你的这句
currentPoint = nextPoint;
要改成
currentPoint.x = nextPoint.x;
currentPoint.y = nextPoint.y;