设计模式之策略模式

策略模式：定义一系列算法，将它们分别封装起来，让他们之间可以相互替换，但不会影响到使用算法的用户。

 

public interface Strategy {
    public void function();
}

public class ConcreteStrategyOne implements Strategy{
    @Override
    public void function() {
        System.out.println("One.");
    }
}

public class ConcreteStrategyTwo implements Strategy{
    @Override
    public void function() {
        System.out.println("Two.");
    }
}

 

public class StrategyContext {
    private Strategy strategy;

    public StrategyContext(Strategy strategy) {
        this.strategy = strategy;
    }

    public void StrategyContextFunction() {
        strategy.function();
    }
}

 

public class StrategyDemo {
    public static void main(String[] args) {
        StrategyContext contextOne = new StrategyContext(new ConcreteStrategyOne());
        contextOne.StrategyContextFunction();

        StrategyContext contextTwo = new StrategyContext(new ConcreteStrategyTwo());
        contextTwo.StrategyContextFunction();
    }
}