Example usage for org.springframework.data.mongodb.core.mapreduce GroupByResults GroupByResults

Introduction

In this page you can find the example usage for org.springframework.data.mongodb.core.mapreduce GroupByResults GroupByResults.

Prototype

public GroupByResults(List<T> mappedResults, Document rawResults) 

Source Link

Usage

From source file:org.springframework.data.mongodb.core.MongoTemplate.java

public <T> GroupByResults<T> group(Criteria criteria, String inputCollectionName, GroupBy groupBy,
        Class<T> entityClass) {

    DBObject dbo = groupBy.getGroupByObject();
    dbo.put("ns", inputCollectionName);

    if (criteria == null) {
        dbo.put("cond", null);
    } else {//from w w  w . j a  va  2  s  .co  m
        dbo.put("cond", mapper.getMappedObject(criteria.getCriteriaObject(), null));
    }
    // If initial document was a JavaScript string, potentially loaded by Spring's Resource abstraction, load it and
    // convert to DBObject

    if (dbo.containsField("initial")) {
        Object initialObj = dbo.get("initial");
        if (initialObj instanceof String) {
            String initialAsString = replaceWithResourceIfNecessary((String) initialObj);
            dbo.put("initial", JSON.parse(initialAsString));
        }
    }

    if (dbo.containsField("$reduce")) {
        dbo.put("$reduce", replaceWithResourceIfNecessary(dbo.get("$reduce").toString()));
    }
    if (dbo.containsField("$keyf")) {
        dbo.put("$keyf", replaceWithResourceIfNecessary(dbo.get("$keyf").toString()));
    }
    if (dbo.containsField("finalize")) {
        dbo.put("finalize", replaceWithResourceIfNecessary(dbo.get("finalize").toString()));
    }

    DBObject commandObject = new BasicDBObject("group", dbo);

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug(String.format("Executing Group with DBObject [%s]", serializeToJsonSafely(commandObject)));
    }

    CommandResult commandResult = executeCommand(commandObject, getDb().getOptions());
    handleCommandError(commandResult, commandObject);

    if (LOGGER.isDebugEnabled()) {
        LOGGER.debug("Group command result = [" + commandResult + "]");
    }

    @SuppressWarnings("unchecked")
    Iterable<DBObject> resultSet = (Iterable<DBObject>) commandResult.get("retval");

    List<T> mappedResults = new ArrayList<T>();
    DbObjectCallback<T> callback = new ReadDbObjectCallback<T>(mongoConverter, entityClass);
    for (DBObject dbObject : resultSet) {
        mappedResults.add(callback.doWith(dbObject));
    }
    GroupByResults<T> groupByResult = new GroupByResults<T>(mappedResults, commandResult);
    return groupByResult;

}

---