Today, let's talk about how to eliminate redundant if...else through strategy mode and factory method. What is the specific strategy mode, you can learn by yourself, and I will not introduce too much here.
Note: If the business scenario is simple, it is recommended to use if...else, because the code logic is simple and easy to understand.
Policy interface
Eat.java
/**
* Policy interface
*
*/
public interface Eat {
public void eatFruit(String fruit);
}Policy class
EatApple.java
/**
* Specific strategies: eating apples
*/
public class EatApple implements Eat{
@Override
public void eatFruit(String fruit) {
System.out.println("Eating apples");
}
}EatBanana.java
/**
* Specific strategies: eating bananas
*/
public class EatBanana implements Eat {
@Override
public void eatFruit(String fruit) {
System.out.println("Eat bananas");
}
}EatPear.java
/**
* Specific Strategies: Eating Pears
*/
public class EatPear implements Eat {
@Override
public void eatFruit(String fruit) {
System.out.println("Eat pear");
}
}Policy context
EatContext.java
/**
* Policy context
*/
public class EatContext {
private Eat eat;
public EatContext(Eat eat) {
this.eat = eat;
}
public void eatContext(String fruit) {
eat.eatFruit(fruit);
}
}Policy Factory Class
EatFactory.java
/**
* Policy Factory Class
*/
public class EatFactory {
private static Map<String, Eat> map = new HashMap<>();
static {
map.put("apple", new EatApple());
map.put("banana", new EatBanana());
map.put("pear", new EatPear());
}
public static Eat getEatStrategy(String fruitType) {
return map.get(fruitType);
}
}test
public class Demo {
public static void main(String[] args) {
String fruit = "apple";
// Introduce specific fruit types and get Apple strategy interface
Eat eat = EatFactory.getEatStrategy(fruit);
// Call specific policy methods
eat.eatFruit(fruit);
}
}Test results:
Eating apples
The first time to write a blog, write bad places, but also hope you leave a message for advice!