java 用枚举替换多if-else

1、定义抽象类

package com.polaris.design;

/**
 * @author ：shi
 * @date ：Created in 2020/8/18 20:15
 * @description：
 * @modified By：
 */
public abstract class GeneralChannelRule {
    public abstract void process();
}

2、实现抽象类方法

package com.polaris.design;

/**
 * @author ：shi
 * @date ：Created in 2020/8/18 20:18
 * @description：
 * @modified By：
 */
public class JDChannelRule extends GeneralChannelRule {

    @Override
    public void process() {
        System.out.println("我们大京东！");
    }
}

3、枚举

package com.polaris.design;

/**
 * @author ：shi
 * @date ：Created in 2020/8/18 20:18
 * @description：
 * @modified By：
 */
public enum ChannelRuleEnum {

    /**
     * 京东
     */
    JD("JD", new JDChannelRule()),

    /**
     * 头条
     */
    TOUTIAO("TOUTIAO", new TouTiaoChannelRule()),

    /**
     * 腾讯
     */
    TENCENT("TENCENT", new TencentChannelRule());

    public String name;

    public GeneralChannelRule channel;

    ChannelRuleEnum(String name, GeneralChannelRule channel) {
        this.name = name;
        this.channel = channel;
    }

    //匹配
    public static ChannelRuleEnum match(String name) {
        ChannelRuleEnum[] values = ChannelRuleEnum.values();
        for (ChannelRuleEnum value : values) {
            if (value.name.equals(name)) {
                return value;
            }
        }
        return null;
    }

    public String getName() {
        return name;
    }

    public GeneralChannelRule getChannel() {
        return channel;
    }
}

4、测试

package com.polaris.design;

/**
 * @author ：shi
 * @date ：Created in 2020/8/18 20:27
 * @description：
 * @modified By：
 */
public class Test1 {

    public static void main(String[] args) {
        String sign = "JD";
        ChannelRuleEnum channelRule = ChannelRuleEnum.match(sign);
        GeneralChannelRule rule = channelRule.channel;
        rule.process();
    }
}

转自：https://mp.weixin.qq.com/s/faQ3yWYM0swfDoEmtwa3nQ