设计模式：享元模式案例
import java.util.HashMap;
import java.util.Map;
// 享元接口
interface ChessPieceFlyweight {
void move(int x, int y); // 外部状态：位置
String getColor(); // 内部状态：颜色
}
// 具体享元类
class ConcreteChessPiece implements ChessPieceFlyweight {
private final String color; // 内部状态
public ConcreteChessPiece(String color) {
this.color = color;
}
@Override
public void move(int x, int y) {
System.out.printf("Moving %s piece to (%d,%d).\n", color, x, y);
}
@Override
public String getColor() {
return color;
}
}
// 享元工厂
class ChessPieceFactory {
private static final Map<String, ChessPieceFlyweight> pieces = new HashMap<>();
public static ChessPieceFlyweight getChessPiece(String color) {
if (!pieces.containsKey(color)) {
ChessPieceFlyweight piece = new ConcreteChessPiece(color);
pieces.put(color, piece);
}
return pieces.get(color);
}
}
// 客户端代码
public class FlyweightExample {
public static void main(String[] args) {
ChessPieceFlyweight whitePiece = ChessPieceFactory.getChessPiece("White");
ChessPieceFlyweight blackPiece = ChessPieceFactory.getChessPiece("Black");
// 棋子被多次移动到不同位置，但对象是共享的
whitePiece.move(1, 2);
blackPiece.move(2, 3);
whitePiece.move(4, 5);
// ... 其他棋子移动操作
}
}