策略模式

IStrategy.java

public interface IStrategy {

	public void operate();
	
}

BackDoor.java

/**
 * 乔国老开后门
 */
public class BackDoor implements IStrategy {

	@Override
	public void operate() {
		System.out.println("找乔国老帮忙，让吴国太给孙权施加压力");
	}

}

GivenGreenLight.java

/**
 * 吴国太开绿灯
 */
public class GivenGreenLight implements IStrategy {

	@Override
	public void operate() {
		System.out.println("求吴国太开绿灯，放行！");
	}

}

BlockEnemy.java

/**
 * 孙夫人断后
 */
public class BlockEnemy implements IStrategy {

	@Override
	public void operate() {
		System.out.println("孙夫人断后，挡住追兵");
	}

}

Context.java

/**
 * 锦囊
 */
public class Context {

	
	private IStrategy strategy;
	
	public Context(IStrategy strategy) {
		this.strategy = strategy;
	}
	
	public void operate() {
		this.strategy.operate();
	}
	
}