public String getKey() {
        return this.key;
    }
<p>
The filter key.
</p>
<ul>
<li>
<p>
<code>product</code> - Filter results based on the specified product identifier.
</p>
</li>
<li>
<p>
<code>provisionedproduct</code> - Filter results based on the provisioned product identifier.
</p>
</li>
</ul>

@return The filter key.</p>
        <ul>
        <li>
        <p>
        <code>product</code> - Filter results based on the specified product identifier.
        </p>
        </li>
        <li>
        <p>
        <code>provisionedproduct</code> - Filter results based on the provisioned product identifier.
        </p>
        </li>
aws-java-sdk-servicecatalog/src/main/java/com/amazonaws/services/servicecatalog/model/ListRecordHistorySearchFilter.java