com.amazon.carbonado.cursor
Class ThrottledCursor<S>

java.lang.Object
  com.amazon.carbonado.cursor.AbstractCursor<S>
      com.amazon.carbonado.cursor.ThrottledCursor<S>

All Implemented Interfaces:

Cursor<S>

public class ThrottledCursor<S>
extends AbstractCursor<S>

Wraps another cursor and fetches results at a reduced speed.

Author:

Brian S O'Neill

Constructor Summary

ThrottledCursor(Cursor<S> cursor, double throttle)

Method Summary

void	close() Call close to release any resources being held by this cursor.
boolean	hasNext() Returns true if this cursor has more elements.
S	next() Returns the next element from this cursor.
int	skipNext(int amount) Skips forward by the specified amount of elements, returning the actual amount skipped.

Methods inherited from class com.amazon.carbonado.cursor.AbstractCursor

copyInto, copyInto, toList, toList

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ThrottledCursor

public ThrottledCursor(Cursor<S> cursor,
                       double throttle)

Parameters:

cursor - cursor to wrap

throttle - 1.0 = fetch at full speed, 0.5 = fetch at half speed, 0.1 = fetch at one tenth speed, etc.

Method Detail

close

public void close()
           throws FetchException

Description copied from interface: Cursor

Call close to release any resources being held by this cursor. Further operations on this cursor will behave as if there are no results.

Throws:

FetchException

hasNext

public boolean hasNext()
                throws FetchException

Description copied from interface: Cursor

Returns true if this cursor has more elements. In other words, returns true if next would return an element rather than throwing an exception.

Throws:

FetchException - if storage layer throws an exception

next

public S next()
       throws FetchException

Description copied from interface: Cursor

Returns the next element from this cursor. This method may be called repeatedly to iterate through the results.

Throws:

FetchException - if storage layer throws an exception

skipNext

public int skipNext(int amount)
             throws FetchException

Description copied from interface: Cursor

Skips forward by the specified amount of elements, returning the actual amount skipped. The actual amount is less than the requested amount only if the end of the results was reached.

Specified by:

skipNext in interface Cursor<S>

Overrides:

skipNext in class AbstractCursor<S>

Parameters:

amount - maximum amount of elements to skip

Returns:

actual amount skipped

Throws:

FetchException - if storage layer throws an exception