types/src/main/java/com/google/common/html/types/SafeHtmlBuilder.java
public SafeHtmlBuilder setPoster(SafeUrl value) {
    if (!POSTER_SAFE_URL_ELEMENT_WHITELIST.contains(elementName)) {
      throw new IllegalArgumentException(
          "Attribute \"poster\" with a SafeUrl value can only be used "
              + "by one of the following elements: "
              + POSTER_SAFE_URL_ELEMENT_WHITELIST);
    }
    return setAttribute("poster", value.getSafeUrlString());
  }
public SafeHtmlBuilder setPoster(SafeUrl value) {
    if (!POSTER_SAFE_URL_ELEMENT_WHITELIST.contains(elementName)) {
      throw new IllegalArgumentException(
          "Attribute \"poster\" with a SafeUrl value can only be used "
              + "by one of the following elements: "
              + POSTER_SAFE_URL_ELEMENT_WHITELIST);
    }
    return setAttribute("poster", value.getSafeUrlString());
  }
Sets the {@code poster} attribute for this element.

<p>The attribute {@code poster} with a {@code SafeUrl} value is allowed on these elements:

<ul>
<li>{@code video}
</ul>

@throws IllegalArgumentException if the {@code poster} attribute with a {@code SafeUrl} value
is not allowed on this element