How to use

find

method

in

org.springframework.data.keyvalue.core.KeyValueOperations

/**
 * Execute a "delete" query, not really a query more of an operation.
 * <p>
 *
 * @param query       The query to run
 * @param queryMethod Used here to find the type of object to match the query
 * @return Collection of deleted objects or the number of deleted objects
 */
private Object executeDeleteQuery(final KeyValueQuery<?> query, final QueryMethod queryMethod) {
  Iterable<?> resultSet = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
  Iterator<?> iterator = resultSet.iterator();
  List<Object> result = new ArrayList<>();
  while (iterator.hasNext()) {
    result.add(this.keyValueOperations.delete(iterator.next()));
  }
  if (queryMethod.isCollectionQuery()) {
    return result;
  } else if (long.class.equals(queryMethod.getReturnedObjectType()) || Long.class
      .equals(queryMethod.getReturnedObjectType())) {
    return result.size();
  } else {
    throw new UnsupportedOperationException(String.format(
        "Illegal returned type: %s. The operation 'deleteBy' accepts only 'long' and 'Collection' as the returned "
            + "object type", queryMethod.getReturnedObjectType()));
  }
}

/**
 * <p>
 * Execute a retrieval query. The query engine will return this in an iterator, which may need conversion to a single
 * domain entity or a stream.
 * </P>
 *
 * @param query       The query to run
 * @param queryMethod Holds metadata about the query, is paging etc
 * @return Query result
 */
private Object executeFindQuery(final KeyValueQuery<?> query, final QueryMethod queryMethod) {
  Iterable<?> resultSet = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
  if (!queryMethod.isCollectionQuery() && !queryMethod.isPageQuery() && !queryMethod.isSliceQuery() && !queryMethod
      .isStreamQuery()) {
    // Singleton result
    return resultSet.iterator().hasNext() ? resultSet.iterator().next() : null;
  }
  if (queryMethod.isStreamQuery()) {
    return StreamUtils.createStreamFromIterator(resultSet.iterator());
  }
  return resultSet;
}

/**
 * @param parameters
 * @param query
 */
@Nullable
@SuppressWarnings({ "unchecked", "rawtypes" })
protected Object doExecute(Object[] parameters, KeyValueQuery<?> query) {
  if (queryMethod.isPageQuery() || queryMethod.isSliceQuery()) {
    Pageable page = (Pageable) parameters[queryMethod.getParameters().getPageableIndex()];
    query.setOffset(page.getOffset());
    query.setRows(page.getPageSize());
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    long count = queryMethod.isSliceQuery() ? 0
        : keyValueOperations.count(query, queryMethod.getEntityInformation().getJavaType());
    return new PageImpl(IterableConverter.toList(result), page, count);
  } else if (queryMethod.isCollectionQuery()) {
    return this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
  } else if (queryMethod.isQueryForEntity()) {
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    return result.iterator().hasNext() ? result.iterator().next() : null;
  }
  throw new UnsupportedOperationException("Query method not supported.");
}

/**
 * @param parameters
 * @param query
 */
@Nullable
@SuppressWarnings({ "unchecked", "rawtypes" })
protected Object doExecute(Object[] parameters, KeyValueQuery<?> query) {
  if (queryMethod.isPageQuery() || queryMethod.isSliceQuery()) {
    Pageable page = (Pageable) parameters[queryMethod.getParameters().getPageableIndex()];
    query.setOffset(page.getOffset());
    query.setRows(page.getPageSize());
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    long count = queryMethod.isSliceQuery() ? 0
        : keyValueOperations.count(query, queryMethod.getEntityInformation().getJavaType());
    return new PageImpl(IterableConverter.toList(result), page, count);
  } else if (queryMethod.isCollectionQuery()) {
    return this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
  } else if (queryMethod.isQueryForEntity()) {
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    return result.iterator().hasNext() ? result.iterator().next() : null;
  }
  throw new UnsupportedOperationException("Query method not supported.");
}

/**
 * @param parameters
 * @param query
 */
@Nullable
@SuppressWarnings({ "unchecked", "rawtypes" })
protected Object doExecute(Object[] parameters, KeyValueQuery<?> query) {
  if (queryMethod.isPageQuery() || queryMethod.isSliceQuery()) {
    Pageable page = (Pageable) parameters[queryMethod.getParameters().getPageableIndex()];
    query.setOffset(page.getOffset());
    query.setRows(page.getPageSize());
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    long count = queryMethod.isSliceQuery() ? 0
        : keyValueOperations.count(query, queryMethod.getEntityInformation().getJavaType());
    return new PageImpl(IterableConverter.toList(result), page, count);
  } else if (queryMethod.isCollectionQuery()) {
    return this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
  } else if (queryMethod.isQueryForEntity()) {
    Iterable<?> result = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
    return result.iterator().hasNext() ? result.iterator().next() : null;
  }
  throw new UnsupportedOperationException("Query method not supported.");
}

query.setRows(pageRequest.getPageSize());
Iterable<?> resultSet = this.keyValueOperations.find(query, queryMethod.getEntityInformation().getJavaType());
List<?> content = IterableConverter.toList(resultSet);