@java.lang.Override
      public com.google.cloud.tasks.v2beta3.HttpTarget.Header build() {
        com.google.cloud.tasks.v2beta3.HttpTarget.Header result = buildPartial();
        if (!result.isInitialized()) {
          throw newUninitializedMessageException(result);
        }
        return result;
      }
<pre>
Defines a header message. A header can have a key and a value.
</pre>

Protobuf type {@code google.cloud.tasks.v2beta3.HttpTarget.Header}
java-tasks/proto-google-cloud-tasks-v2beta3/src/main/java/com/google/cloud/tasks/v2beta3/HttpTarget.java