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>
Output only. The primary instance that acts as the source of replication
for the secondary instances.
</pre>

<code>
.google.cloud.memorystore.v1.CrossInstanceReplicationConfig.RemoteInstance primary_instance = 1 [(.google.api.field_behavior) = OUTPUT_ONLY];
</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/CrossInstanceReplicationConfig.java