java spi

1.新建一个接口及其两个实现类

package com.zy.javaspi;

public interface UploadCDN {
    void upload(String yrl);
}

package com.zy.javaspi;

public class QiyiCDN implements UploadCDN {
    @Override
    public void upload(String yrl) {
        System.out.println("上传到爱奇艺");
    }
}

package com.zy.javaspi;

public class YoukuCDN implements UploadCDN {
    @Override
    public void upload(String yrl) {
        System.out.println("上传到优酷");
    }
}

2.在resources下新建META-INF包，然后新建services文件夹，然后新建以接口为名称的文件，里面写上实现类的全限定名称

 

文件内容：

com.zy.javaspi.QiyiCDN
com.zy.javaspi.YoukuCDN

3.测试

public class Test {
    public static void main(String[] args) {
        //测试javaspi
        ServiceLoader<UploadCDN> load = ServiceLoader.load(UploadCDN.class);
        for (UploadCDN uploadCDN:load){
            uploadCDN.upload("filepath");
        }
}