com.fasterxml.jackson工具类通过注解过滤给前端返回json，没有value则移除对应的key

   <dependency>
            <groupId>com.liferay</groupId>
            <artifactId>com.fasterxml.jackson.annotations</artifactId>
            <version>2.10.3.LIFERAY-PATCHED-1</version>
        </dependency>

import com.fasterxml.jackson.annotation.JsonInclude;
import lombok.Data;

@JsonInclude(JsonInclude.Include.NON_NULL)
@Data
public class AudioDomain {


    /**
     * 开始时间
     */
    private String startTime;

    /**
     * 结束时间
     */
    private String endTime;


}