java策略模式例子
时间: 2023-11-24 15:49:17 浏览: 41
Java中的策略模式可以通过以下例子来说明:
首先,我们需要定义一个策略接口,例如:
```
public interface Strategy {
int doOperation(int num1, int num2);
}
```
然后,我们可以实现不同的策略类,例如:
```
public class OperationAdd implements Strategy {
public int doOperation(int num1, int num2) {
return num1 + num2;
}
}
public class OperationSubtract implements Strategy {
public int doOperation(int num1, int num2) {
return num1 - num2;
}
}
public class OperationMultiply implements Strategy {
public int doOperation(int num1, int num2) {
return num1 * num2;
}
}
```
接下来,我们需要一个Context类来使用这些策略,例如:
```
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);
}
}
```
最后,我们可以使用这些类来实现策略模式,例如:
```
public class StrategyPatternDemo {
public static void main(String[] args) {
Context context = new Context(new OperationAdd());
System.out.println("10 + 5 = " + context.executeStrategy(10, 5));
context = new Context(new OperationSubtract());
System.out.println("10 - 5 = " + context.executeStrategy(10, 5));
context = new Context(new OperationMultiply());
System.out.println("10 * 5 = " + context.executeStrategy(10, 5));
}
}
```
这个例子中,我们定义了一个策略接口和三个不同的策略类,然后使用Context类来使用这些策略。在main方法中,我们可以看到不同的策略被使用来执行不同的操作。