Java obj克隆問題

Question

如果您是善良的人，我需要以下代碼的幫助。 基本上我有一個樹節點，記得它的父節點，深度級別和他的當前狀態（二維數組）。 大多數變量名稱都寫在我的母語，我希望這不是一個問題：

public class Nod implements Cloneable { 

private Nod parinte;//parent node 
private int[][] stare;//state 
private int cost;//depth-level 
private String actiune;//the action used to obtain this node 
private volatile int hashCode = 0; 

public boolean equals(Object obj) 
{ 
    if(this == obj) 
    { 
     return true; 
    } 
    if (!(obj instanceof Nod)) 
    { 
     return false; 
    } 
    Nod nod = (Nod)obj; 
    return cost == nod.getCost() && actiune.equals(nod.getActiune()) 
      && stare.equals(nod.getStareNod()); 
} 

public int hashCode() 
{ 
    StringBuffer strBuff = new StringBuffer(); 
    try 
    { 
     int n = Problema.Dimensiune();//returns the dimension of state matrix 
     for (int i=0;i<n;i++) 
      for (int j=0;j<n;j++) 
       strBuff.append(stare[i][j]); 
     strBuff.append(cost); 
     strBuff.append(actiune); 

     String str = strBuff.toString(); 
     hashCode = str.hashCode(); 

    } 
    catch (IOException e) { 
     e.printStackTrace(); 
    } 

    return hashCode; 
} 

    public Object clone() throws CloneNotSupportedException 
    { 
     return super.clone(); 
    } 


public static boolean goUp(int[][] st) throws IOException 
{ 

    int n = Problema.Dimensiune(); 
    boolean ok = false; 
    int[][] a = st; 

    for (int i=0;i<n;i++) 
     for (int j=0;j<n;j++) 
     { 
      if (a[i][j] == 0) 
       if (i != 0) 
        ok = true; 
     } 
    return ok; 
} 

public static boolean goDown(int[][] st) throws IOException 
{ 

    int n = Problema.Dimensiune(); 
    boolean ok = false; 
    int[][] a = st; 

    for (int i=0;i<n;i++) 
     for (int j=0;j<n;j++) 
     { 
      if (a[i][j] == 0) 
       if (i != (n-1)) 
        ok = true; 
     } 
    return ok; 
} 

public static boolean goLeft(int[][] st) throws IOException 
{ 

    int n = Problema.Dimensiune(); 
    boolean ok = false; 
    int[][] a = st; 

    for (int i=0;i<n;i++) 
     for (int j=0;j<n;j++) 
     { 
      if (a[i][j] == 0) 
       if (j != 0) 
        ok = true; 
     } 
    return ok; 
} 

public static boolean goRight(int[][] st) throws IOException 
{ 

    int n = Problema.Dimensiune(); 
    boolean ok = false; 
    int[][] a = st; 

    for (int i=0;i<n;i++) 
     for (int j=0;j<n;j++) 
     { 
      if (a[i][j] == 0) 
       if (j != (n-1)) 
        ok = true; 
     } 
    return ok; 
} 


public static int[] Zero(int[][] st) throws IOException 
{ 

    int[][] a = st; 
    int n = Problema.Dimensiune(); 
    int[] b = new int[2]; 

    for (int i=0;i<n;i++) 
     for (int j=0;j<n;j++) 
      if (a[i][j] == 0) 
      { 
       b[0] = i; 
       b[1] = j; 
      } 

    return b; 
} 

public static int[][] Actiune(int[][] st, String s) throws IOException 
{ 

    int[][] a = st; 
    int[] b = Zero(st); 

    if ((goRight(st) == true) && (s == "right")) 
    { 

     a[b[0]][b[1]] = a[b[0]][b[1]+1]; 
     a[b[0]][b[1]+1] = 0; 
    } 

    if ((goLeft(st) == true) && (s == "left")) 
    { 

     a[b[0]][b[1]] = a[b[0]][b[1]-1]; 
     a[b[0]][b[1]-1] = 0; 
    } 

    if ((goUp(st) == true) && (s == "up")) 
    { 

     a[b[0]][b[1]] = a[b[0]-1][b[1]]; 
     a[b[0]-1][b[1]] = 0; 
    } 

    if ((goDown(st) == true) && (s == "down")) 
    { 

     a[b[0]][b[1]] = a[b[0]+1][b[1]]; 
     a[b[0]+1][b[1]] = 0; 
    } 

    return a; 
} 

public Nod(){} 

public Nod (int[][] st) 
{ 
    parinte = null; 
    stare = st; 
    cost = 0; 
    actiune = null; 
} 

public Nod (Nod nod) 
{ 
    parinte = nod.parinte; 
    stare = nod.stare; 
    cost = nod.cost; 
    actiune = nod.actiune; 
} 

public Nod(Nod nodp, String ac) throws IOException 
{ 
    this.parinte = nodp; 
    this.cost = parinte.getCost()+1; 
    this.actiune = ac; 
    this.stare = Actiune(parinte.getStareNod(),actiune); 
} 

public void setCost(int cost) 
{ 
    this.cost = cost; 
} 

public int getCost(){ 
    return this.cost; 
} 

public void setStareNod(int[][] stare) 
{ 
    this.stare = stare; 
} 

public int[][] getStareNod(){ 
    return this.stare; 
} 

public void setNodParinte(Nod parinte) 
{ 
    this.parinte = parinte; 
} 

public Nod getNodParinte() throws IOException{ 
    return this.parinte; 
} 

public void setActiune(String actiune) 
{ 
    this.actiune = actiune; 
} 

public String getActiune() 
{ 
    return this.actiune; 
} 

}

現在，我創建一個初始節點後，從它一個子節點。問題是，當我創建子節點時，父節點的2D數組與子節點的數組變得完全相同。我試圖克隆節點對象，但沒有解決它。我很感激，如果有人有一個ideea如何解決它並分享它。

public class test { 

public static void main(String[] args) throws IOException, CloneNotSupportedException 
{ 
    int[][] p = Problema.stareInitiala(); 
    Nod nod = new Nod(p); 

    Nod nodc = (Nod) nod.clone(); 
    Nod nod1 = new Nod(nodc,"right"); 

    Nod nod1c = (Nod) nod1.clone(); 
    Nod nod2 = new Nod(nod1c,"up"); 

    if (nod.getStareNod().equals(nod.getStareNod())) 
     System.out.print("ok"); 
    else 
     System.out.print("not ok"); 
} 

}

因此，如果P = {{7,2,4}，{5,0,6}，{8,3,1}} if語句應該返回 「不正常」 ，但是我得到了「ok」的信息。

Answer 1

克隆機制沒有任何破裂或錯誤。只是一羣或程序員誰不明白它，這是一個適合你的課程。

public Object clone() { 
    try { 
     Nod clone = (Nod)super.clone(); 
     clone.stare = (int[][])stare.clone(); 
     return clone; 
    } catch (CloneNotSupportedException cnse) { 
     //won't happen; 
     throw new RuntimeError("Won't happen"); 
    } 
} 

此實現假設克隆想要使用與原始父代相同的父代。如果情況並非如此，您需要克隆它，或者將父項設置爲null。

Answer 2

您可能想要查看Object的clone（）方法的documentation。默認克隆實現（即，如果您實現了Cloneable，則執行此操作）執行淺拷貝。這可能不是你想要的，你可以通過編寫自己的複製方法來更好。