改动的只有Context类和客户端类： 

/**
 * 工厂模式与策略模式相结合
 */
public class Context {
    private Strategy strategy;

    /***
     * 这里不再传入具体的策略对象 而是传入要操作的策略标志
     * 创建实例的过程 由客户端到了Context
     * @param type
     */
    public Context(String type) {
        switch (type) {
            case "A":
                strategy = new ConcreteStrategyA();
                break;
            case "B":
                strategy = new ConcreteStrategyB();
                break;
            case "C":
                strategy = new ConcreteStrategyC();
                break;
        }
    }


    /**
     * 根据具体的策略对象 调用其算法
     */
    public void ContextInterface() {
//        这里可以Return计算结果给客户端
        strategy.AlgorithmInterface();
    }
}

public class Main {
    public static void main(String[] args) {
        Context context;
        context = new Context("A");
        context.ContextInterface();

        context = new Context("B");
        context.ContextInterface();

        context = new Context("C");
        context.ContextInterface();
    }
}