Java Code Examples for com.mongodb.client.AggregateIterable#first()

The following examples show how to use com.mongodb.client.AggregateIterable#first() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example 1

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 统计频数
 *
 * @param collectionName
 * @param match
 * @param distinctField
 * @return
 */
public int distinctCount(String collectionName, Document match, String distinctField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, addToSet("_array", "$" + distinctField))
                    , project(new Document("_num", new Document("$size", "$_array")))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.getInteger("_num");
    }
    return 0;
}

Example 2

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 获取不一样的记录
 *
 * @param collectionName
 * @param match
 * @param distinctField
 * @return
 */
public List distinct(String collectionName, Document match, String distinctField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, addToSet("_array", "$" + distinctField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return (List) first.get("_array");
    }
    return null;
}

Example 3

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 最大统计
 *
 * @param collectionName
 * @param match
 * @param maxField
 * @return
 */
public Object max(String collectionName, Document match, String maxField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, Accumulators.max("_max", "$" + maxField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.get("_max");
    }
    return null;
}

Example 4

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 最小统计
 *
 * @param collectionName
 * @param match
 * @param minField
 * @return
 */
public Object min(String collectionName, Document match, String minField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, Accumulators.min("_min", "$" + minField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.get("_min");
    }
    return null;
}

Example 5

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 合统计
 *
 * @param collectionName
 * @param match
 * @param sumField
 * @return
 */
public Double sum(String collectionName, Document match, String sumField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, Accumulators.sum("_sum", "$" + sumField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.getDouble("_sum");
    }
    return null;
}

Example 6

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 平均统计
 *
 * @param collectionName
 * @param match
 * @param avgField
 * @return
 */
public Double avg(String collectionName, Document match, String avgField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, Accumulators.avg("_avg", "$" + avgField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.getDouble("_avg");
    }
    return null;
}

Example 7

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 最近统计
 *
 * @param collectionName
 * @param match
 * @param lastField
 * @param sort
 * @return
 */
public Object last(String collectionName, Document match, String lastField, Document sort) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , sort(sort)
                    , group(null, Accumulators.last("_last", "$" + lastField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.get("_last");
    }
    return null;
}

Example 8

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 标准差统计
 *
 * @param collectionName
 * @param match
 * @param stdDevField
 * @return
 */
public Double stdDevPop(String collectionName, Document match, String stdDevField) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , group(null, Accumulators.stdDevPop("_stdDev", "$" + stdDevField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.getDouble("_stdDev");
    }
    return null;
}

Example 9

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 采样标准差统计
 *
 * @param collectionName
 * @param match
 * @param stdDevField
 * @param sampleSize
 * @return
 */
public Double stdDevSamp(String collectionName, Document match, String stdDevField, int sampleSize) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match)
                    , sample(sampleSize)
                    , group(null, Accumulators.stdDevSamp("_stdDev", "$" + stdDevField))
            )
    );
    Document first = aggregate.first();
    if (first != null) {
        return first.getDouble("_stdDev");
    }
    return null;
}

Example 10

Source File: MongoDao.java From Liudao with GNU General Public License v3.0

5 votes

/**
 * 统计值 是否在统计结果（gte最小值）中
 *
 * @param collectionName 集合名
 * @param match          match条件
 * @param field          统计字段
 * @param value          统计值
 * @param minCount       最小值
 * @return
 */
public boolean inSortMap(String collectionName, Document match, String field, Object value, int minCount) {
    AggregateIterable<Document> aggregate = getDB().getCollection(collectionName).aggregate(
            Arrays.asList(
                    match(match.append(field, value))
                    , group("$" + field, Accumulators.sum("_count", 1))
                    , match(new Document("_count", new Document("$gte", minCount)))
            )
    );

    Document first = aggregate.first();
    return first == null ? false : true;
}