public Builder mergePullTarget(com.google.cloud.tasks.v2beta2.PullTarget value) {
      if (pullTargetBuilder_ == null) {
        if (targetTypeCase_ == 4
            && targetType_ != com.google.cloud.tasks.v2beta2.PullTarget.getDefaultInstance()) {
          targetType_ =
              com.google.cloud.tasks.v2beta2.PullTarget.newBuilder(
                      (com.google.cloud.tasks.v2beta2.PullTarget) targetType_)
                  .mergeFrom(value)
                  .buildPartial();
        } else {
          targetType_ = value;
        }
        onChanged();
      } else {
        if (targetTypeCase_ == 4) {
          pullTargetBuilder_.mergeFrom(value);
        } else {
          pullTargetBuilder_.setMessage(value);
        }
      }
      targetTypeCase_ = 4;
      return this;
    }
<pre>
Pull target.

A pull queue is a queue that has a
[PullTarget][google.cloud.tasks.v2beta2.PullTarget].
</pre>

<code>.google.cloud.tasks.v2beta2.PullTarget pull_target = 4;</code>
java-tasks/proto-google-cloud-tasks-v2beta2/src/main/java/com/google/cloud/tasks/v2beta2/Queue.java