public String getDuration() {
        return this.duration;
    }
<p>
Specifies the time period that the boost applies to. For example, to make the boost apply to documents with the
field value within the last month, you would use "2628000s". Once the field value is beyond the specified range,
the effect of the boost drops off. The higher the importance, the faster the effect drops off. If you don't
specify a value, the default is 3 months. The value of the field is a numeric string followed by the character
"s", for example "86400s" for one day, or "604800s" for one week.
</p>
<p>
Only applies to <code>DATE</code> fields.
</p>

@return Specifies the time period that the boost applies to. For example, to make the boost apply to documents
        with the field value within the last month, you would use "2628000s". Once the field value is beyond the
        specified range, the effect of the boost drops off. The higher the importance, the faster the effect
        drops off. If you don't specify a value, the default is 3 months. The value of the field is a numeric
        string followed by the character "s", for example "86400s" for one day, or "604800s" for one week. </p>
        <p>
        Only applies to <code>DATE</code> fields.
aws-java-sdk-kendra/src/main/java/com/amazonaws/services/kendra/model/Relevance.java