org.apache.lucene.search
Class TimeLimitedCollector

java.lang.Object
  org.apache.lucene.search.HitCollector
      org.apache.lucene.search.TimeLimitedCollector

public class TimeLimitedCollector
extends HitCollector

The TimeLimitedCollector is used to timeout search requests that take longer than the maximum allowed search time limit. After this time is exceeded, the search thread is stopped by throwing a TimeExceeded Exception.

Nested Class Summary

static class

TimeLimitedCollector.TimeExceededException Thrown when elapsed search time exceeds allowed search time.

Field Summary

boolean	DEFAULT_GREEDY Default for isGreedy().
static int	DEFAULT_RESOLUTION Default timer resolution.

Constructor Summary

TimeLimitedCollector(HitCollector hc, long timeAllowed)
Create a TimeLimitedCollector wrapper over another HitCollector with a specified timeout.

Method Summary

void	collect(int doc, float score) Calls collect() on the decorated HitCollector.
static long	getResolution() Return the timer resolution.
boolean	isGreedy() Checks if this time limited collector is greedy in collecting the last hit.
void	setGreedy(boolean greedy) Sets whether this time limited collector is greedy.
static void	setResolution(long newResolution) Set the timer resolution.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_RESOLUTION

public static final int DEFAULT_RESOLUTION

Default timer resolution.

See Also:

setResolution(long), Constant Field Values

DEFAULT_GREEDY

public boolean DEFAULT_GREEDY

Default for isGreedy().

See Also:

isGreedy()

Constructor Detail

TimeLimitedCollector

public TimeLimitedCollector(HitCollector hc,
                            long timeAllowed)

Create a TimeLimitedCollector wrapper over another HitCollector with a specified timeout.

Parameters:

hc - the wrapped HitCollector

timeAllowed - max time allowed for collecting hits after which TimeLimitedCollector.TimeExceededException is thrown

Method Detail

collect

public void collect(int doc,
                    float score)

Calls collect() on the decorated HitCollector.

Specified by:

collect in class HitCollector

Throws:

TimeLimitedCollector.TimeExceededException - if the time allowed has been exceeded.

getResolution

public static long getResolution()

Return the timer resolution.

See Also:

setResolution(long)

setResolution

public static void setResolution(long newResolution)

Set the timer resolution. The default timer resolution is 20 milliseconds. This means that a search required to take no longer than 800 milliseconds may be stopped after 780 to 820 milliseconds.
Note that:

• Finer (smaller) resolution is more accurate but less efficient.
• Setting resolution to less than 5 milliseconds will be silently modified to 5 milliseconds.
• Setting resolution smaller than current resolution might take effect only after current resolution. (Assume current resolution of 20 milliseconds is modified to 5 milliseconds, then it can take up to 20 milliseconds for the change to have effect.

isGreedy

public boolean isGreedy()

Checks if this time limited collector is greedy in collecting the last hit. A non greedy collector, upon a timeout, would throw a TimeLimitedCollector.TimeExceededException without allowing the wrapped collector to collect current doc. A greedy one would first allow the wrapped hit collector to collect current doc and only then throw a TimeLimitedCollector.TimeExceededException.

See Also:

setGreedy(boolean)

setGreedy

public void setGreedy(boolean greedy)

Sets whether this time limited collector is greedy.

Parameters:

greedy - true to make this time limited greedy

See Also:

isGreedy()