sdf/Engine.java

package com.car.model;

import java.util.ArrayList;
import java.util.List;

/**
 * 引擎类 - 汽车的核心组件
 * 与Car类是组合关系，包含Piston组件的组合关系
 */
public class Engine {
    private String type; // 引擎类型
    private int horsepower; // 马力
    private double displacement; // 排量
    private List<Piston> pistons; // 活塞列表 - 组合关系
    
    /**
     * 构造方法
     * @param type 引擎类型
     * @param horsepower 马力
     * @param displacement 排量
     * @param pistonCount 活塞数量
     */
    public Engine(String type, int horsepower, double displacement, int pistonCount) {
        this.type = type;
        this.horsepower = horsepower;
        this.displacement = displacement;
        this.pistons = new ArrayList<>(pistonCount);
        
        // 初始化活塞
        for (int i = 0; i < pistonCount; i++) {
            pistons.add(new Piston(85, 88, "Aluminum", 10));
        }
    }
    
    // 添加活塞方法
    public void addPiston(Piston piston) {
        pistons.add(piston);
    }
    
    // 替换活塞方法
    public boolean replacePiston(int index, Piston newPiston) {
        if (index >= 0 && index < pistons.size()) {
            pistons.set(index, newPiston);
            return true;
        }
        return false;
    }
    
    // getter and setter methods
    public String getType() {
        return type;
    }
    
    public void setType(String type) {
        this.type = type;
    }
    
    public int getHorsepower() {
        return horsepower;
    }
    
    public void setHorsepower(int horsepower) {
        this.horsepower = horsepower;
    }
    
    public double getDisplacement() {
        return displacement;
    }
    
    public void setDisplacement(double displacement) {
        this.displacement = displacement;
    }
    
    public List<Piston> getPistons() {
        return new ArrayList<>(pistons); // 返回副本，保持封装性
    }
    
    @Override
    public String toString() {
        return "Engine [type=" + type + ", horsepower=" + horsepower + ", displacement=" + displacement + ", pistonsCount=" + pistons.size() + "]";
    }
}