Java Code Examples for com.google.cloud.spanner.KeySet#getKeys()

/**
 * Builds a query that returns the rows associated with a key set with additional SQL-where.
 * The {@link org.springframework.cloud.gcp.data.spanner.core.mapping.Where} of the {@code persistentEntity} parameter
 * is ignored, you should pass the SQL-where as a {@code whereClause} parameter.
 * The secondary {@code index} will be used instead of the table name when the corresponding parameter is not null.
 * @param keySet the key set whose members to get.
 * @param persistentEntity the persistent entity of the table.
 * @param <T> the type of the persistent entity
 * @param writeConverter a converter to convert key values as needed to bind to the query statement.
 * @param mappingContext mapping context
 * @param whereClause SQL where clause
 * @param index the secondary index name
 * @return the Spanner statement to perform the retrieval.
 */
public static <T> Statement buildQuery(KeySet keySet,
		SpannerPersistentEntity<T> persistentEntity, SpannerCustomConverter writeConverter,
		SpannerMappingContext mappingContext, String whereClause, String index) {
	List<String> orParts = new ArrayList<>();
	List<String> tags = new ArrayList<>();
	List keyParts = new ArrayList();
	int tagNum = 0;
	List<SpannerPersistentProperty> keyProperties = persistentEntity.getFlattenedPrimaryKeyProperties();

	for (Key key : keySet.getKeys()) {
		StringJoiner andJoiner = new StringJoiner(" AND ");
		Iterator parentKeyParts = key.getParts().iterator();
		while (parentKeyParts.hasNext()) {
			SpannerPersistentProperty keyProp = keyProperties.get(tagNum % keyProperties.size());
			String tagName = "tag" + tagNum;
			andJoiner.add(keyProp.getColumnName() + " = @" + tagName);
			tags.add(tagName);
			keyParts.add(parentKeyParts.next());
			tagNum++;
		}
		orParts.add(andJoiner.toString());
	}
	String keyClause = orParts.stream().map(s -> "(" + s + ")").collect(Collectors.joining(" OR "));
	String condition = combineWithAnd(keyClause, whereClause);
	String sb = "SELECT " + getColumnsStringForSelect(persistentEntity, mappingContext, true) + " FROM "
			+ (StringUtils.isEmpty(index) ? persistentEntity.tableName() : String.format("%s@{FORCE_INDEX=%s}", persistentEntity.tableName(), index))
			+ (condition.isEmpty() ? "" : " WHERE " + condition);
	return buildStatementFromSqlWithArgs(sb, tags, null, writeConverter,
			keyParts.toArray(), null);
}
 

private static long sizeOf(KeySet keySet) {
  long result = 0;
  for (Key k : keySet.getKeys()) {
    result += sizeOf(k);
  }
  for (KeyRange kr : keySet.getRanges()) {
    result += sizeOf(kr);
  }
  return result;
}