com.mongodb.operation

接口 BatchCursor<T>

类型参数:

T - The type of documents the cursor contains

所有超级接口:

java.lang.AutoCloseable, java.io.Closeable, java.util.Iterator<java.util.List<T>>

所有已知子接口:

MapReduceBatchCursor<T>

@NotThreadSafe
public interface BatchCursor<T>
extends java.util.Iterator<java.util.List<T>>, java.io.Closeable

MongoDB returns query results as batches, and this interface provideds an iterator over those batches. The first call to the next method will return the first batch, and subsequent calls will trigger a request to get the next batch of results. Clients can control the batch size by setting the batchSize property between calls to next.

从以下版本开始:

3.0

MongoDB documentation

OP_GET_MORE

方法概要

限定符和类型	方法和说明
void	close()
int	getBatchSize() Gets the batch size to use when requesting the next batch.
ServerAddress	getServerAddress() Returns the server address
ServerCursor	getServerCursor() Returns the server cursor
boolean	hasNext() Returns true if another batch of results exists.
java.util.List<T>	next() Returns the next batch of results.
void	setBatchSize(int batchSize) Sets the batch size to use when requesting the next batch.
java.util.List<T>	tryNext() A special next() case that returns the next batch if available or null.

从接口继承的方法 java.util.Iterator

forEachRemaining, remove

方法详细资料

close

void close()

指定者:

close 在接口中 java.lang.AutoCloseable

指定者:

close 在接口中 java.io.Closeable

hasNext

boolean hasNext()

Returns true if another batch of results exists. A tailable cursor will block until another batch exists.

指定者:

hasNext 在接口中 java.util.Iterator<java.util.List<T>>

返回:

true if another batch exists

next

java.util.List<T> next()

Returns the next batch of results. A tailable cursor will block until another batch exists.

指定者:

next 在接口中 java.util.Iterator<java.util.List<T>>

返回:

the next batch of results

抛出:

java.util.NoSuchElementException - if no next batch exists

setBatchSize

void setBatchSize(int batchSize)

Sets the batch size to use when requesting the next batch. This is the number of documents to request in the next batch.

参数:

batchSize - the non-negative batch size. 0 means to use the server default.

getBatchSize

int getBatchSize()

Gets the batch size to use when requesting the next batch. This is the number of documents to request in the next batch.

返回:

the non-negative batch size. 0 means to use the server default.

tryNext

java.util.List<T> tryNext()

A special next() case that returns the next batch if available or null.

Tailable cursors are an example where this is useful. A call to tryNext() may return null, but in the future calling tryNext() would return a new batch if a document had been added to the capped collection.

返回:

the next batch if available or null.

MongoDB documentation

Tailable Cursor

getServerCursor

ServerCursor getServerCursor()

Returns the server cursor

返回:

ServerCursor

getServerAddress

ServerAddress getServerAddress()

Returns the server address

返回:

ServerAddress