Cursor

Abstract Value Members

abstract def collect[M[_]](maxDocs: Int = Int.MaxValue, err: ErrorHandler[M[T]] = Cursor.FailOnError[M[T]]())(implicit cbf: CanBuildFrom[M[_], T, M[T]], ec: ExecutionContext): Future[M[T]]

Collects all the documents into a collection of type M[T].
Collects all the documents into a collection of type M[T].
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited).
err
The binary operator to be applied when failing to get the next response. Exception or Fail raised within the suc function cannot be recovered by this error handler. (default: Cursor.FailOnError)
```
import scala.concurrent.ExecutionContext
import reactivemongo.api.Cursor
import reactivemongo.api.bson.BSONDocument
import reactivemongo.api.bson.collection.BSONCollection
def foo(collection: BSONCollection, query: BSONDocument)(
  implicit ec: ExecutionContext) = {
  val cursor = collection.find(query).cursor[BSONDocument]()
  // return the 3 first documents in a Vector[BSONDocument].
  cursor.collect[Vector](3, Cursor.FailOnError[Vector[BSONDocument]]())
}
```
Definition Classes
CursorCompatAPI
abstract def foldBulks[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, Iterator[T]) ⇒ State[A], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

Applies a binary operator to a start value and all bulks of documents retrieved by this cursor, going first to last.
Applies a binary operator to a start value and all bulks of documents retrieved by this cursor, going first to last.
A
the result type of the binary operator
```
import reactivemongo.api.Cursor
import scala.concurrent.ExecutionContext
case class Person(name: String, age: Int)
def foo(cursor: Cursor[Person])(implicit ec: ExecutionContext) =
  cursor.foldBulks(Nil: Seq[Person])(
    (s, bulk: Iterator[Person]) => Cursor.Cont(s ++ bulk),
    { (l, e) => println("last valid value: " + l); Cursor.Fail(e) })
```
z
the initial value
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited). The actual document count can exceed this, when this maximum devided by the batch size given a non-zero remainder.
suc
The binary operator to be applied when the next response is successfully read.
err
The binary operator to be applied when failing to get the next response. Exception or Fail raised within the suc function cannot be recovered by this error handler.
abstract def foldBulksM[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, Iterator[T]) ⇒ Future[State[A]], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

Applies a binary operator to a start value and all bulks of documents retrieved by this cursor, going first to last.
Applies a binary operator to a start value and all bulks of documents retrieved by this cursor, going first to last.
A
the result type of the binary operator
```
import scala.concurrent.{ ExecutionContext, Future }
import reactivemongo.api.Cursor
case class Person(name: String, age: Int)
def foo(cursor: Cursor[Person])(implicit ec: ExecutionContext) =
  cursor.foldBulksM(Nil: Seq[Person])(
    { (s, bulk: Iterator[Person]) =>
     Future.successful(Cursor.Cont(s ++ bulk))
   },
    { (l, e) =>
      println("last valid value: " + l)
      Cursor.Fail[Seq[Person]](e)
    })
```
z
the initial value
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited). The actual document count can exceed this, when this maximum devided by the batch size given a non-zero remainder.
suc
The binary operator to be applied when the next response is successfully read. This must be safe, and any error must be returned as Future.failed[State[A]].
err
The binary operator to be applied when failing to get the next response. Exception or Fail raised within the suc function cannot be recovered by this error handler.
abstract def foldWhile[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ State[A], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
A
the result type of the binary operator
```
import reactivemongo.api.Cursor
import scala.concurrent.ExecutionContext
case class Person(name: String, age: Int)
def foo(cursor: Cursor[Person])(implicit ec: ExecutionContext) =
  cursor.foldWhile(Nil: Seq[Person])((s, p) => Cursor.Cont(s :+ p),
    { (l, e) => println("last valid value: " + l); Cursor.Fail(e) })
```
z
the initial value
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited).
suc
The binary operator to be applied when the next document is successfully read.
err
The binary operator to be applied when failing to get the next response. Exception or Fail raised within the suc function cannot be recovered by this error handler.
abstract def foldWhileM[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ Future[State[A]], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
A
the result type of the binary operator
```
import scala.concurrent.{ ExecutionContext, Future }
import reactivemongo.api.Cursor
case class Person(name: String, age: Int)
def foo(cursor: Cursor[Person])(implicit ec: ExecutionContext) =
  cursor.foldWhileM(Nil: Seq[Person])(
    (s, p) => Future.successful(Cursor.Cont(s :+ p)),
    { (l, e) =>
      println("last valid value: " + l)
      Cursor.Fail[Seq[Person]](e)
    })
```
z
the initial value
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited).
suc
The binary operator to be applied when the next document is successfully read. This must be safe, and any error must be returned as Future.failed[State[A]].
err
The binary operator to be applied when failing to get the next response. Exception or Fail raised within the suc function cannot be recovered by this error handler.

abstract def head(implicit ec: ExecutionContext): Future[T]

Returns the first document matching the query, or fails with Cursor.NoSuchResultException if none.

import scala.concurrent.{ ExecutionContext, Future }

import reactivemongo.api.bson.BSONDocument
import reactivemongo.api.bson.collection.BSONCollection

def first(query: BSONDocument)(collection: BSONCollection)(
  implicit ec: ExecutionContext): Future[BSONDocument] = {
  val cursor = collection.find(query).cursor[BSONDocument]()
  // return option of the first element.
  cursor.head
}

abstract def headOption(implicit ec: ExecutionContext): Future[Option[T]]

Returns the first document matching the query, if any.

import scala.concurrent.{ ExecutionContext, Future }

import reactivemongo.api.bson.BSONDocument

import reactivemongo.api.bson.collection.BSONCollection

def maybeFirst(query: BSONDocument)(collection: BSONCollection)(
  implicit ec: ExecutionContext): Future[Option[BSONDocument]] = {
  val cursor = collection.find(query).cursor[BSONDocument]()
  // return option of the first element.
  cursor.headOption
}

abstract def peek[M[_]](maxDocs: Int)(implicit cbf: CanBuildFrom[M[_], T, M[T]], ec: ExecutionContext): Future[Result[M[T]]]

EXPERIMENTAL: The cursor state, if already resolved.
EXPERIMENTAL: The cursor state, if already resolved.

Definition Classes
CursorCompatAPI

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
def +(other: String): String

Implicit information
This member is added by an implicit conversion from Cursor[T] to any2stringadd[Cursor[T]] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd
def ->[B](y: B): (Cursor[T], B)

Implicit information
This member is added by an implicit conversion from Cursor[T] to ArrowAssoc[Cursor[T]] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
@inline()
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0

Definition Classes
Any
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
def ensuring(cond: (Cursor[T]) ⇒ Boolean, msg: ⇒ Any): Cursor[T]

Implicit information
This member is added by an implicit conversion from Cursor[T] to Ensuring[Cursor[T]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: (Cursor[T]) ⇒ Boolean): Cursor[T]

Implicit information
This member is added by an implicit conversion from Cursor[T] to Ensuring[Cursor[T]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: Boolean, msg: ⇒ Any): Cursor[T]

Implicit information
This member is added by an implicit conversion from Cursor[T] to Ensuring[Cursor[T]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: Boolean): Cursor[T]

Implicit information
This member is added by an implicit conversion from Cursor[T] to Ensuring[Cursor[T]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
def fold[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ A)(implicit ec: ExecutionContext): Future[A]

Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
Applies a binary operator to a start value and all elements retrieved by this cursor, going first to last.
A
the result type of the binary operator
```
import scala.concurrent.ExecutionContext
import reactivemongo.api.Cursor
case class Person(name: String, age: Int)
def foo(cursor: Cursor[Person])(implicit ec: ExecutionContext) =
  cursor.foldWhile(Nil: Seq[Person])((s, p) => Cursor.Cont(s :+ p),
    { (l, e) => println("last valid value: " + l); Cursor.Fail(e) })
```
z
the initial value
maxDocs
the maximum number of documents to be retrieved (-1 for unlimited).
suc
The binary operator to be applied when the next document is successfully read.
def formatted(fmtstr: String): String

Implicit information
This member is added by an implicit conversion from Cursor[T] to StringFormat[Cursor[T]] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
@inline()
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
def →[B](y: B): (Cursor[T], B)

Implicit information
This member is added by an implicit conversion from Cursor[T] to ArrowAssoc[Cursor[T]] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc

Related Docs: object Cursor | package api

trait Cursor[T] extends CursorCompatAPI[T]

Abstract Value Members

abstract def collect[M[_]](maxDocs: Int = Int.MaxValue, err: ErrorHandler[M[T]] = Cursor.FailOnError[M[T]]())(implicit cbf: CanBuildFrom[M[_], T, M[T]], ec: ExecutionContext): Future[M[T]]

abstract def foldBulks[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, Iterator[T]) ⇒ State[A], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

abstract def foldBulksM[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, Iterator[T]) ⇒ Future[State[A]], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

abstract def foldWhile[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ State[A], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

abstract def foldWhileM[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ Future[State[A]], err: ErrorHandler[A] = FailOnError[A]())(implicit ec: ExecutionContext): Future[A]

abstract def head(implicit ec: ExecutionContext): Future[T]

abstract def headOption(implicit ec: ExecutionContext): Future[Option[T]]

abstract def peek[M[_]](maxDocs: Int)(implicit cbf: CanBuildFrom[M[_], T, M[T]], ec: ExecutionContext): Future[Result[M[T]]]

Concrete Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

def +(other: String): String

def ->[B](y: B): (Cursor[T], B)

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

def clone(): AnyRef

def ensuring(cond: (Cursor[T]) ⇒ Boolean, msg: ⇒ Any): Cursor[T]

def ensuring(cond: (Cursor[T]) ⇒ Boolean): Cursor[T]

def ensuring(cond: Boolean, msg: ⇒ Any): Cursor[T]

def ensuring(cond: Boolean): Cursor[T]

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

def fold[A](z: ⇒ A, maxDocs: Int = 1)(suc: (A, T) ⇒ A)(implicit ec: ExecutionContext): Future[A]

def formatted(fmtstr: String): String

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

def →[B](y: B): (Cursor[T], B)

Inherited from CursorCompatAPI[T]

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from Cursor[T] to any2stringadd[Cursor[T]]

Inherited by implicit conversion StringFormat from Cursor[T] to StringFormat[Cursor[T]]

Inherited by implicit conversion Ensuring from Cursor[T] to Ensuring[Cursor[T]]

Inherited by implicit conversion ArrowAssoc from Cursor[T] to ArrowAssoc[Cursor[T]]

Ungrouped