你所做的是浅拷贝，你需要的是深拷贝。试试这个

public class Cell {

boolean alive = false;

protected Cell clone() {
    return new Cell(this);
}

public Cell() {

}

public Cell(Cell cell) {
    this.alive = cell.alive;
}

boolean isAlive() {
    return alive;
}

void kill() {
    alive = false;
}

void born() {
    alive = true;
}

static int count(Cell[][] cell, int j, int k) {
    return 1;
}

public static void main(String[] args) {
    Cell[][] CellList = new Cell[2][3];
    CellList[0][1] = new Cell();
    nextGen(CellList);
}

public static Cell[][] nextGen(Cell[][] CellList) {

    Cell[][] Copy = deepArrayCopy(CellList);

    for (int i = 0; i < Copy.length; i++) {
        for (int n = 0; n < Copy[i].length; n++) {
            if (Copy[i][n].isAlive()) {
                if (Cell.count(Copy, i, n) <= 1 || Cell.count(Copy, i, n) >= 4) {
                    CellList[i][n].kill();
                }
            } else {
                if (Cell.count(Copy, i, n) == 3) {
                    CellList[i][n].born();
                }
            }
        }
    }

    return CellList;
}

public static Cell[][] deepArrayCopy(Cell[][] celllist) {
    Cell[][] copy = new Cell[celllist.length][celllist[0].length];
    for (int i = 0; i < celllist.length; i++) {
        for (int k = 0; k < celllist[i].length; k++) {
            if (celllist[i][k] != null)
                copy[i][k] = celllist[i][k].clone();
        }
    }
    return copy;
}

}