Java ViewQuery.limit方法代码示例

import org.ektorp.ViewQuery; //导入方法依赖的package包/类
@Override
protected DataSet materializeMainSchemaTable(Table table, List<Column> columns, int firstRow, int maxRows) {
    // the connector represents a handle to the the couchdb "database".
    final String databaseName = table.getName();
    final CouchDbConnector connector = _couchDbInstance.createConnector(databaseName, false);

    ViewQuery query = new ViewQuery().allDocs().includeDocs(true);

    if (maxRows > 0) {
        query = query.limit(maxRows);
    }
    if (firstRow > 1) {
        final int skip = firstRow - 1;
        query = query.skip(skip);
    }

    final StreamingViewResult streamingView = connector.queryForStreamingView(query);

    final List<SelectItem> selectItems = columns.stream().map(SelectItem::new).collect(Collectors.toList());
    return new CouchDbDataSet(selectItems, streamingView);
}
 

import org.ektorp.ViewQuery; //导入方法依赖的package包/类
@Override
public void emitTuples()
{
  ViewQuery viewQuery = getViewQuery();
  if (pageSize > 0) {
    viewQuery.limit(pageSize);
  }
  if (nextPageKey != null) {
    viewQuery.startKey(nextPageKey);
  }
  if (skip) {
    viewQuery.skip(1);
  }
  ViewResult result = store.queryStore(viewQuery);
  List<ViewResult.Row> rows = result.getRows();
  try {
    for (ViewResult.Row row : result.getRows()) {
      T tuple = getTuple(row);
      outputPort.emit(tuple);
    }
  } catch (Throwable cause) {
    Throwables.propagate(cause);
  }
  if (rows.size() > 0) {
    // Use the last row as the start key and skip one item
    // In case we reach the end we will continue to make the request with last row till there is more data available
    // in the store
    nextPageKey = rows.get(rows.size() - 1).getKey();
    // The skip option should only be used with small values, as skipping a large range of documents this way is inefficient.
    skip = true;
  }
}
 

import org.ektorp.ViewQuery; //导入方法依赖的package包/类
private ViewQuery getViewQuery(StatementFilter filter, int limit,
		boolean ascending) {
	ViewQuery viewQuery = new ViewQuery(mapper).designDocId(
			"_design/statements").viewName(viewName);
	Object startKey = ascending ? getStartKey(filter) : getEndKey(filter);
	if (startKey != null) {
		viewQuery.startKey(startKey);
	}
	Object endKey = ascending ? getEndKey(filter) : getStartKey(filter);
	if (endKey != null) {
		viewQuery.endKey(endKey);
	}
	if (!ascending) {
		viewQuery.descending(true);
	}
	// fetch one too many for paging-check
	viewQuery.limit(limit + 1);

	String startId = filter.getStartId();
	if (startId != null) {
		viewQuery.startDocId(startId);
	}
	viewQuery.includeDocs(true);

	viewQuery.staleOkUpdateAfter();

	return viewQuery;
}
 

import org.ektorp.ViewQuery; //导入方法依赖的package包/类
@Override
public List<GameRun> findAllGameRun(int limit) {
	ViewQuery q = createQuery("by_result");
	q.includeDocs(true);
	q.descending(true);
	if (limit != -1) {
		q.limit(limit);
	}
	return db.queryView(q, type);
}
 

import org.ektorp.ViewQuery; //导入方法依赖的package包/类
/**
 * Configures Ektorp's {@link ViewQuery} with the given {@link ViewParams}.
 * 
 * @param view the Ektorp object to be configured
 * @param params the parameters that shall be used 
 */
public void configure(ViewQuery view, ViewParams params) {
    if (params.getAttachments() != null) {
        throw new UnsupportedViewParameterException("attachments");
    }
    if (params.getAttEncodingInfo() != null) {
        throw new UnsupportedViewParameterException("att_encoding_info");
    }
    if (params.getConflicts() != null) {
        throw new UnsupportedViewParameterException("conflicts");
    }
    if (params.getDescending() != null) {
        view.descending(params.getDescending());
    }
    if (params.getGroup() != null) {
        view.group(params.getGroup());
    }
    if (params.getIncludeDocs() != null) {
        view.includeDocs(params.getIncludeDocs());
    }
    if (params.getInclusiveEnd() != null) {
        view.inclusiveEnd(params.getInclusiveEnd());
    }
    if (params.getReduce() != null) {
        view.reduce(params.getReduce());
    }
    if (params.getUpdateSeq() != null) {
        view.updateSeq(params.getUpdateSeq());
    }
    if (params.getEndKey() != null) {
        view.endKey(params.getEndKey());
    }
    if (params.getEndKeyDocId() != null) {
        view.endDocId(params.getEndKeyDocId());
    }
    if (params.getGroupLevel() != null) {
        view.groupLevel(params.getGroupLevel());
    }
    if (params.getKey() != null) {
        view.key(params.getKey());
    }
    if (params.getLimit() != null) {
        view.limit(params.getLimit());
    }
    if (params.getSkip() != null) {
        view.skip(params.getSkip());
    }
    if (params.getStale() != null) {
        if ("ok".equals(params.getStale())) {
            view.staleOk(true);
        } else if ("update_after".equals(params.getStale())) {
            view.staleOkUpdateAfter();
        }
    }
    if (params.getStartKey() != null) {
        view.startKey(params.getStartKey());
    }
    if (params.getStartKeyDocId() != null) {
        view.startDocId(params.getStartKeyDocId());
    }

    //

    if (params.getDesignDocument() != null) {
        view.designDocId("_design/" + params.getDesignDocument());
    }
    if (params.getView() != null) {
        view.viewName(params.getView());
    }
}