Package com.mongodb.client.model

Class Accumulators

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static BsonField accumulator​(String fieldName, String initFunction, String accumulateFunction, String mergeFunction)
      Creates an $accumulator pipeline stage
      static BsonField accumulator​(String fieldName, String initFunction, String accumulateFunction, String mergeFunction, String finalizeFunction)
      Creates an $accumulator pipeline stage
      static BsonField accumulator​(String fieldName, String initFunction, String accumulateFunction, String mergeFunction, String finalizeFunction, String lang)
      Creates an $accumulator pipeline stage
      static BsonField accumulator​(String fieldName, String initFunction, List<String> initArgs, String accumulateFunction, List<String> accumulateArgs, String mergeFunction, String finalizeFunction)
      Creates an $accumulator pipeline stage
      static BsonField accumulator​(String fieldName, String initFunction, List<String> initArgs, String accumulateFunction, List<String> accumulateArgs, String mergeFunction, String finalizeFunction, String lang)
      Creates an $accumulator pipeline stage
      static <TExpression>
      BsonField      		 addToSet​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing all unique values that results from applying the given expression to each document in a group of documents that share the same group by key.
      static <TExpression>
      BsonField      		 avg​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the average of the values of the given expression when applied to all members of the group.
      static <TExpression>
      BsonField      		 first​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the value of the given expression when applied to the first member of the group.
      static <TExpression>
      BsonField      		 last​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the value of the given expression when applied to the last member of the group.
      static <TExpression>
      BsonField      		 max​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the maximum of the values of the given expression when applied to all members of the group.
      static <TExpression>
      BsonField      		 mergeObjects​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the result of merging the fields of the documents.
      static <TExpression>
      BsonField      		 min​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the minimum of the values of the given expression when applied to all members of the group.
      static <TExpression>
      BsonField      		 push​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing an array of all values that results from applying an expression to each document in a group of documents that share the same group by key.
      static <TExpression>
      BsonField      		 stdDevPop​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the sample standard deviation of the values of the given expression when applied to all members of the group.
      static <TExpression>
      BsonField      		 stdDevSamp​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the sample standard deviation of the values of the given expression when applied to all members of the group.
      static <TExpression>
      BsonField      		 sum​(String fieldName, TExpression expression)
      Gets a field name for a $group operation representing the sum of the values of the given expression when applied to all members of the group.

    • Method Detail

      • sum

        public static <TExpression> BsonField sum​(String fieldName,
                                          TExpression expression)
        Gets a field name for a $group operation representing the sum of the values of the given expression when applied to all members of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $sum

      • avg

        public static <TExpression> BsonField avg​(String fieldName,
                                          TExpression expression)
        Gets a field name for a $group operation representing the average of the values of the given expression when applied to all members of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $avg

      • first

        public static <TExpression> BsonField first​(String fieldName,
                                            TExpression expression)
        Gets a field name for a $group operation representing the value of the given expression when applied to the first member of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $first

      • last

        public static <TExpression> BsonField last​(String fieldName,
                                           TExpression expression)
        Gets a field name for a $group operation representing the value of the given expression when applied to the last member of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $last

      • max

        public static <TExpression> BsonField max​(String fieldName,
                                          TExpression expression)
        Gets a field name for a $group operation representing the maximum of the values of the given expression when applied to all members of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $max

      • min

        public static <TExpression> BsonField min​(String fieldName,
                                          TExpression expression)
        Gets a field name for a $group operation representing the minimum of the values of the given expression when applied to all members of the group.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $min

      • push

        public static <TExpression> BsonField push​(String fieldName,
                                           TExpression expression)
        Gets a field name for a $group operation representing an array of all values that results from applying an expression to each document in a group of documents that share the same group by key.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $push

      • addToSet

        public static <TExpression> BsonField addToSet​(String fieldName,
                                               TExpression expression)
        Gets a field name for a $group operation representing all unique values that results from applying the given expression to each document in a group of documents that share the same group by key.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        MongoDB documentation
        $addToSet

      • mergeObjects

        public static <TExpression> BsonField mergeObjects​(String fieldName,
                                                   TExpression expression)
        Gets a field name for a $group operation representing the result of merging the fields of the documents. If documents to merge include the same field name, the field, in the resulting document, has the value from the last document merged for the field.
        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        Since:
        4.4
        MongoDB documentation
        $mergeObjects

      • stdDevPop

        public static <TExpression> BsonField stdDevPop​(String fieldName,
                                                TExpression expression)
        Gets a field name for a $group operation representing the sample standard deviation of the values of the given expression when applied to all members of the group.

        Use if the values encompass the entire population of data you want to represent and do not wish to generalize about a larger population.

        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        Since:
        3.2
        MongoDB documentation
        $stdDevPop
        Since server release
        3.2

      • stdDevSamp

        public static <TExpression> BsonField stdDevSamp​(String fieldName,
                                                 TExpression expression)
        Gets a field name for a $group operation representing the sample standard deviation of the values of the given expression when applied to all members of the group.

        Use if the values encompass a sample of a population of data from which to generalize about the population.

        Type Parameters:
        TExpression - the expression type
        Parameters:
        fieldName - the field name
        expression - the expression
        Returns:
        the field
        Since:
        3.2
        MongoDB documentation
        $stdDevSamp
        Since server release
        3.2

      • accumulator

        public static BsonField accumulator​(String fieldName,
                                    String initFunction,
                                    String accumulateFunction,
                                    String mergeFunction)
        Creates an $accumulator pipeline stage
        Parameters:
        fieldName - the field name
        initFunction - a function used to initialize the state
        accumulateFunction - a function used to accumulate documents
        mergeFunction - a function used to merge two internal states, e.g. accumulated on different shards or threads. It returns the resulting state of the accumulator.
        Returns:
        the $accumulator pipeline stage
        Since:
        4.1
        MongoDB documentation
        $accumulator
        Since server release
        4.4

      • accumulator

        public static BsonField accumulator​(String fieldName,
                                    String initFunction,
                                    String accumulateFunction,
                                    String mergeFunction,
                                    @Nullable
                                    String finalizeFunction)
        Creates an $accumulator pipeline stage
        Parameters:
        fieldName - the field name
        initFunction - a function used to initialize the state
        accumulateFunction - a function used to accumulate documents
        mergeFunction - a function used to merge two internal states, e.g. accumulated on different shards or threads. It returns the resulting state of the accumulator.
        finalizeFunction - a function used to finalize the state and return the result (may be null)
        Returns:
        the $accumulator pipeline stage
        Since:
        4.1
        MongoDB documentation
        $accumulator
        Since server release
        4.4

      • accumulator

        public static BsonField accumulator​(String fieldName,
                                    String initFunction,
                                    @Nullable
                                    List<String> initArgs,
                                    String accumulateFunction,
                                    @Nullable
                                    List<String> accumulateArgs,
                                    String mergeFunction,
                                    @Nullable
                                    String finalizeFunction)
        Creates an $accumulator pipeline stage
        Parameters:
        fieldName - the field name
        initFunction - a function used to initialize the state
        initArgs - init function’s arguments (may be null)
        accumulateFunction - a function used to accumulate documents
        accumulateArgs - additional accumulate function’s arguments (may be null). The first argument to the function is ‘state’.
        mergeFunction - a function used to merge two internal states, e.g. accumulated on different shards or threads. It returns the resulting state of the accumulator.
        finalizeFunction - a function used to finalize the state and return the result (may be null)
        Returns:
        the $accumulator pipeline stage
        Since:
        4.1
        MongoDB documentation
        $accumulator
        Since server release
        4.4

      • accumulator

        public static BsonField accumulator​(String fieldName,
                                    String initFunction,
                                    String accumulateFunction,
                                    String mergeFunction,
                                    @Nullable
                                    String finalizeFunction,
                                    String lang)
        Creates an $accumulator pipeline stage
        Parameters:
        fieldName - the field name
        initFunction - a function used to initialize the state
        accumulateFunction - a function used to accumulate documents
        mergeFunction - a function used to merge two internal states, e.g. accumulated on different shards or threads. It returns the resulting state of the accumulator.
        finalizeFunction - a function used to finalize the state and return the result (may be null)
        lang - a language specifier
        Returns:
        the $accumulator pipeline stage
        Since:
        4.1
        MongoDB documentation
        $accumulator
        Since server release
        4.4

      • accumulator

        public static BsonField accumulator​(String fieldName,
                                    String initFunction,
                                    @Nullable
                                    List<String> initArgs,
                                    String accumulateFunction,
                                    @Nullable
                                    List<String> accumulateArgs,
                                    String mergeFunction,
                                    @Nullable
                                    String finalizeFunction,
                                    String lang)
        Creates an $accumulator pipeline stage
        Parameters:
        fieldName - the field name
        initFunction - a function used to initialize the state
        initArgs - init function’s arguments (may be null)
        accumulateFunction - a function used to accumulate documents
        accumulateArgs - additional accumulate function’s arguments (may be null). The first argument to the function is ‘state’.
        mergeFunction - a function used to merge two internal states, e.g. accumulated on different shards or threads. It returns the resulting state of the accumulator.
        finalizeFunction - a function used to finalize the state and return the result (may be null)
        lang - a language specifier
        Returns:
        the $accumulator pipeline stage
        Since:
        4.1
        MongoDB documentation
        $accumulator
        Since server release
        4.4