JAVA策略模式-案例

拼搏现实的明天。 2024-03-27 19:24 11阅读 0赞

## Java策略模式 ##

// 定义策略接口  
    public interface Strategy {  
        public int doOperation(int num1, int num2);  
    }  
      
    // 实现具体策略：加法  
    public class OperationAdd implements Strategy {  
        @Override  
        public int doOperation(int num1, int num2) {  
            return num1 + num2;  
        }  
    }  
      
    // 实现具体策略：减法  
    public class OperationSubtract implements Strategy {  
        @Override  
        public int doOperation(int num1, int num2) {  
            return num1 - num2;  
        }  
    }  
      
    // 实现具体策略：乘法  
    public class OperationMultiply implements Strategy {  
        @Override  
        public int doOperation(int num1, int num2) {  
            return num1 * num2;  
        }  
    }  
      
    //上下文类，将使用策略  
    public class Context {  
        private Strategy strategy;  
      
        public Context(Strategy strategy) {  
            this.strategy = strategy;  
        }  
      
        public int executeStrategy(int num1, int num2) {  
            return strategy.doOperation(num1, num2);  
        }  
    }  
      
    // 测试策略模式  
    public class StrategyPatternDemo {  
        public static void main(String[] args) {  
            Context context = new Context(new OperationAdd());   // 创建上下文并设置加法策略  
            System.out.println("10 + 5 = " + context.executeStrategy(10, 5));   // 执行加法策略  
      
            context = new Context(new OperationSubtract());   // 创建上下文并设置减法策略  
            System.out.println("10 - 5 = " + context.executeStrategy(10, 5));   // 执行减法策略  
      
            context = new Context(new OperationMultiply());   // 创建上下文并设置乘法策略  
            System.out.println("10 * 5 = " + context.executeStrategy(10, 5));   // 执行乘法策略  
        }  
    }