public Builder setFamilies(int index, java.lang.String value) {
      if (value == null) {
        throw new NullPointerException();
      }
      ensureFamiliesIsMutable();
      families_.set(index, value);
      bitField0_ |= 0x00000200;
      onChanged();
      return this;
    }
<pre>
Output only. Families of the node type.
For node types to be in the same cluster
they must share at least one element in the `families`.
</pre>

<code>repeated string families = 13 [(.google.api.field_behavior) = OUTPUT_ONLY];</code>

@param index The index to set the value at.
@param value The families to set.
@return This builder for chaining.
java-vmwareengine/proto-google-cloud-vmwareengine-v1/src/main/java/com/google/cloud/vmwareengine/v1/NodeType.java