public Builder clearContents() {
      if (contentsBuilder_ == null) {
        contents_ = java.util.Collections.emptyList();
        bitField0_ = (bitField0_ & ~0x00000040);
        onChanged();
      } else {
        contentsBuilder_.clear();
      }
      return this;
    }
<pre>
Optional. Input only. Immutable. The content to cache
</pre>

<code>
repeated .google.cloud.vertexai.v1.Content contents = 4 [(.google.api.field_behavior) = OPTIONAL, (.google.api.field_behavior) = IMMUTABLE, (.google.api.field_behavior) = INPUT_ONLY];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/CachedContent.java