public boolean equals(TableIdentifier that) {
    if (that == null)
      return false;
    if (this == that)
      return true;

    boolean this_present_catalog = true && this.isSetCatalog();
    boolean that_present_catalog = true && that.isSetCatalog();
    if (this_present_catalog || that_present_catalog) {
      if (!(this_present_catalog && that_present_catalog))
        return false;
      if (!this.catalog.equals(that.catalog))
        return false;
    }

    boolean this_present_database = true && this.isSetDatabase();
    boolean that_present_database = true && that.isSetDatabase();
    if (this_present_database || that_present_database) {
      if (!(this_present_database && that_present_database))
        return false;
      if (!this.database.equals(that.database))
        return false;
    }

    boolean this_present_tableName = true && this.isSetTableName();
    boolean that_present_tableName = true && that.isSetTableName();
    if (this_present_tableName || that_present_tableName) {
      if (!(this_present_tableName && that_present_tableName))
        return false;
      if (!this.tableName.equals(that.tableName))
        return false;
    }

    return true;
  }
Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise
iceberg/iceberg-handler/src/main/java/org/apache/iceberg/mr/hive/compaction/evaluator/amoro/TableIdentifier.java