private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance,
            com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance.Builder,
            com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstanceOrBuilder>
        getPrimaryInstanceFieldBuilder() {
      if (primaryInstanceBuilder_ == null) {
        primaryInstanceBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance,
                com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance
                    .Builder,
                com.google.cloud.memorystore.v1.CrossInstanceReplicationConfig
                    .RemoteInstanceOrBuilder>(
                getPrimaryInstance(), getParentForChildren(), isClean());
        primaryInstance_ = null;
      }
      return primaryInstanceBuilder_;
    }
<pre>
Optional. Details of the primary instance that is used as the replication
source for this secondary instance.

This field is only set for a secondary instance.
</pre>

<code>
.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance primary_instance = 2 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/CrossInstanceReplicationConfig.java