枚举单例模式实践

枚举单例模式简单实践，用枚举构建一个百度API的client唯一实例。

public enum BaiduApi {
    API;
    public static final String APP_ID = "43543";
    public static final String API_KEY = "K9dpjF0HqltT534ePgPuhQCrhsG";
    public static final String SECRET_KEY = "8fd9WaY7BeKkT34534KMY3rIs3oSSFmzxRep0";
    private AipNlp client;
    private BaiduApi(){
        client=new AipNlp(APP_ID, API_KEY, SECRET_KEY);
    }
    public AipNlp getClient(){
        return this.client;
    }
}

测试类

    @Test
    public void testBaiduApi(){
        System.out.println(BaiduApi.API.getClient());
        System.out.println(BaiduApi.API.getClient());
        System.out.println(BaiduApi.API.getClient());
    }

结果为

com.baidu.aip.nlp.AipNlp@65e579dc
com.baidu.aip.nlp.AipNlp@65e579dc
com.baidu.aip.nlp.AipNlp@65e579dc

在程序运行过程中获取的是唯一的client。