Package org.apache.solr.search

Class QueryLimits

java.lang.Object

org.apache.solr.search.QueryLimits

All Implemented Interfaces:

org.apache.lucene.index.QueryTimeout

public class QueryLimits
extends Object
implements org.apache.lucene.index.QueryTimeout

Represents the limitations on the query. These limits might be wall clock time, cpu time, memory, or other resource limits. Exceeding any specified limit will cause shouldExit() to return true the next time it is checked (it may be checked in either Lucene code or Solr code)

Field Summary

Fields

Modifier and Type	Field	Description
static QueryLimits	NONE

Constructor Summary

Constructors

Constructor	Description
QueryLimits(SolrQueryRequest req, SolrQueryResponse rsp)	Implementors of a Query Limit should add an if block here to activate it, and typically this if statement will hinge on hasXXXLimit() static method attached to the implementation class.

Method Summary

Modifier and Type	Method	Description
String	formatExceptionMessage(String label)	Format an exception message with optional label and details from limitStatusMessage().
static QueryLimits	getCurrentLimits()	Helper method to retrieve the current QueryLimits from SolrRequestInfo.getRequestInfo() if it exists, otherwise it returns NONE.
boolean	isLimitsEnabled()	Return true if there are any limits enabled for the current request.
String	limitStatusMessage()	Method to diagnose limit exceeded.
boolean	maybeExitWithPartialResults(String label)	If limit is reached then depending on the request param CommonParams.PARTIAL_RESULTS either mark it as partial result in the response and signal the caller to return, or throw an exception.
boolean	shouldExit()

Methods inherited from class java.lang.Object

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

Field Detail

NONE

public static QueryLimits NONE

Constructor Detail

QueryLimits

public QueryLimits(SolrQueryRequest req,
                   SolrQueryResponse rsp)

Implementors of a Query Limit should add an if block here to activate it, and typically this if statement will hinge on hasXXXLimit() static method attached to the implementation class.

Parameters:

req - the current SolrQueryRequest.

rsp - the current SolrQueryResponse.

Method Detail

shouldExit

public boolean shouldExit()

Specified by:

shouldExit in interface org.apache.lucene.index.QueryTimeout

formatExceptionMessage

public String formatExceptionMessage(String label)

Format an exception message with optional label and details from limitStatusMessage().

maybeExitWithPartialResults

public boolean maybeExitWithPartialResults(String label)
                                    throws QueryLimitsExceededException

If limit is reached then depending on the request param CommonParams.PARTIAL_RESULTS either mark it as partial result in the response and signal the caller to return, or throw an exception.

Parameters:

label - optional label to indicate the caller.

Returns:

true if the caller should stop processing and return partial results, false otherwise.

Throws:

QueryLimitsExceededException - if CommonParams.PARTIAL_RESULTS request parameter is false and limits have been reached.

limitStatusMessage

public String limitStatusMessage()

Method to diagnose limit exceeded. Note that while this should always list the exceeded limit, it may also nominate additional limits that have been exceeded since the actual check that cause the failure. This gap is intentional to avoid overly complicated (and possibly expensive) tracking code that would have to run within the shouldExit method. This method should only be used to report a failure since it incurs the cost of rechecking every configured limit and does not short circuit.

Returns:

A string describing the state pass/fail state of each limit specified for this request.

isLimitsEnabled

public boolean isLimitsEnabled()

Return true if there are any limits enabled for the current request.

getCurrentLimits

public static QueryLimits getCurrentLimits()

Helper method to retrieve the current QueryLimits from SolrRequestInfo.getRequestInfo() if it exists, otherwise it returns NONE.