public synchronized MixedFormatConnectorMetadata get() {
      if (metadata == null) {
        try (ThreadContextClassLoader ignored = new ThreadContextClassLoader(classLoader)) {
          metadata = metadataFactory.create();
        }
      }
      return metadata;
    }
This is used to guarantee one transaction to one {@link MixedFormatConnectorMetadata}
amoro-format-mixed/amoro-mixed-trino/src/main/java/org/apache/amoro/trino/MixedFormatTransactionManager.java