/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.query;
import org.apache.jena.riot.RIOT ;
import org.apache.jena.riot.system.RiotLib ;
import org.apache.jena.sparql.SystemARQ ;
import org.apache.jena.sparql.algebra.optimize.TransformOrderByDistinctApplication ;
import org.apache.jena.sparql.core.assembler.AssemblerUtils ;
import org.apache.jena.sparql.engine.http.Service ;
import org.apache.jena.sparql.expr.aggregate.AggregateRegistry ;
import org.apache.jena.sparql.function.FunctionRegistry ;
import org.apache.jena.sparql.lib.Metadata ;
import org.apache.jena.sparql.mgt.ARQMgt ;
import org.apache.jena.sparql.mgt.Explain ;
import org.apache.jena.sparql.mgt.Explain.InfoLevel ;
import org.apache.jena.sparql.mgt.SystemInfo ;
import org.apache.jena.sparql.pfunction.PropertyFunctionRegistry ;
import org.apache.jena.sparql.util.Context ;
import org.apache.jena.sparql.util.MappingRegistry ;
import org.apache.jena.sparql.util.Symbol ;
import org.apache.jena.system.JenaSystem ;
import org.slf4j.Logger ;
import org.slf4j.LoggerFactory ;
/** ARQ - miscellaneous settings */
public class ARQ
{
// Initialization statics must be first in the class to avoid
// problems with recursive initialization. Specifcally,
// initLock being null because elsewhere started the initialization
// and is calling into the TDB class.
// The best order is:
// Initialization controls
// All calculated constants
// static { JenaSystem.init() ; }
// Otherwise, using constants after JenaSystem.init can lead to null being seen.
private static volatile boolean initialized = false ;
private static final Object initLock = new Object() ;
// Initialization notes:
// 1/ No use of ARQConstants before the initialization block. (Can be afterwards.)
// Risk is
// ARQConstants -> OWL -> ModelFactory -> jena initialization
// -> ARQ.init while initializing -> StageBuilder.init -> NodeConst -> rdf.type -> OWL
// recursing initialization, hits NPE via OWL.
// 2/ stageGenerator constant must be set before the call to ARQ.init.
/** Name of the execution logger */
public static final String logExecName = "org.apache.jena.arq.exec" ;
/** Name of the information logger */
public static final String logInfoName = "org.apache.jena.arq.info" ;
/** Name of the logger for remote HTTP requests */
public static final String logHttpRequestName = "org.apache.jena.arq.service" ;
private static final Logger logExec = LoggerFactory.getLogger(logExecName) ;
private static final Logger logInfo = LoggerFactory.getLogger(logInfoName) ;
private static final Logger logHttpRequest = LoggerFactory.getLogger(logHttpRequestName) ;
/** The execution logger */
public static Logger getExecLogger() { return logExec ; }
/** The information logger */
public static Logger getInfoLogger() { return logInfo ; }
/** The HTTP Request logger */
public static Logger getHttpRequestLogger() { return logHttpRequest ; }
/** Symbol to enable logging of execution.
* Must also set log4j, or other logging system,
* for logger "com.hp.hpl.jena.sparql.exec"
* e.g. log4j.properties -- log4j.logger.com.hp.hpl.jena.sparql.exec=INFO
* See the <a href="http://jena.apache.org/documentation/query/logging.html">ARQ Logging Documentation</a>.
*/
public static final Symbol symLogExec = SystemARQ.allocSymbol("logExec") ;
/** Get the currently global execution logging setting */
public static Explain.InfoLevel getExecutionLogging() { return (Explain.InfoLevel)ARQ.getContext().get(ARQ.symLogExec) ; }
/** Set execution logging - logging is to logger "org.apache.jena.arq.exec" at level INFO.
* An appropriate logging configuration is also required.
*/
public static void setExecutionLogging(Explain.InfoLevel infoLevel)
{
if ( InfoLevel.NONE.equals(infoLevel) )
{
ARQ.getContext().unset(ARQ.symLogExec) ;
return ;
}
ARQ.getContext().set(ARQ.symLogExec, infoLevel) ;
// if ( ! getExecLogger().isInfoEnabled() )
// getExecLogger().warn("Attempt to enable execution logging but the logger '"+logExecName+"' is not logging at level INFO") ;
}
/** IRI for ARQ */
public static final String arqIRI = "http://jena.hpl.hp.com/#arq" ;
/** Root of ARQ-defined parameter names */
public static final String arqParamNS = "http://jena.apache.org/ARQ#" ;
/** Prefix for ARQ-defined parameter names */
public static final String arqSymbolPrefix = "arq" ;
/** Stick exactly to the spec.
*/
public static final Symbol strictSPARQL =
SystemARQ.allocSymbol("strictSPARQL") ;
/** Controls bNode labels as <_:...> or not -
* that is a pseudo URIs.
* This does not affect [] or _:a bNodes as variables in queries.
*/
public static final Symbol constantBNodeLabels =
SystemARQ.allocSymbol("constantBNodeLabels") ;
/** Enable built-in property functions - also called "magic properties".
* These are properties in triple patterns that need
* calculation, not matching. See ARQ documentation for more details.
* rdfs:member and http://jena.apache.org/ARQ/list#member are provided.
*/
public static final Symbol enablePropertyFunctions =
SystemARQ.allocSymbol("enablePropertyFunctions") ;
/** Enable logging of execution timing.
*/
public static final Symbol enableExecutionTimeLogging =
SystemARQ.allocSymbol("enableExecutionTimeLogging") ;
/** If true, XML result sets written will contain the graph bNode label
* See also inputGraphBNodeLabels
*/
public static final Symbol outputGraphBNodeLabels =
SystemARQ.allocSymbol("outputGraphBNodeLabels") ;
/** If true, XML result sets will use the bNode label in the result set itself.
* See also outputGraphBNodeLabels
*/
public static final Symbol inputGraphBNodeLabels =
SystemARQ.allocSymbol("inputGraphBNodeLabels") ;
/** Turn on processing of blank node labels in queries */
public static void enableBlankNodeResultLabels() { enableBlankNodeResultLabels(true) ; }
/** Turn on/off processing of blank node labels in queries */
public static void enableBlankNodeResultLabels(boolean val)
{
Boolean b = val;
globalContext.set(inputGraphBNodeLabels, b) ;
globalContext.set(outputGraphBNodeLabels, b) ;
}
/**
* Set timeout. The value of this symbol gives thevalue of the timeout in milliseconds
* <ul>
* <li>A Number; the long value is used</li>
* <li>A string, e.g. "1000", parsed as a number</li>
* <li>A string, as two numbers separated by a comma, e.g. "500,10000" parsed as two numbers</li>
* </ul>
* @see QueryExecution#setTimeout(long)
* @see QueryExecution#setTimeout(long,long)
*/
public static final Symbol queryTimeout = SystemARQ.allocSymbol("queryTimeout") ;
// This can't be a context constant because NodeValues don't look in the context.
// /**
// * Context symbol controlling Roman Numerals in Filters.
// */
// public static final Symbol enableRomanNumerals = ARQConstants.allocSymbol("romanNumerals") ;
/**
* Context key for StageBuilder used in BGP compilation
*/
public static final Symbol stageGenerator = SystemARQ.allocSymbol("stageGenerator") ;
/**
* Context key to control hiding non-distinuished variables
*/
public static final Symbol hideNonDistiguishedVariables = SystemARQ.allocSymbol("hideNonDistiguishedVariables") ;
/**
* Use the SAX parser for XML result sets. The default is to use StAX for
* full streaming of XML results. The SAX parser takes a copy of the result set
* before giving the ResultSet to the calling application.
*/
public static final Symbol useSAX = SystemARQ.allocSymbol("useSAX") ;
/**
* Indicate whether duplicate select and groupby variables are allowed.
* If false, duplicates are silently supressed; it's not an error.
*/
public static final boolean allowDuplicateSelectColumns = false ;
/**
* Determine which regular expression system to use.
* The value of this context entry should be a string or symbol
* of one of the following:
* javaRegex : use java.util.regex (support features outside the strict SPARQL regex language)
* xercesRegex : use the internal XPath regex engine (more compliant)
*/
public static final Symbol regexImpl = SystemARQ.allocSymbol("regexImpl") ;
/** Symbol to name java.util.regex regular expression engine */
public static final Symbol javaRegex = SystemARQ.allocSymbol("javaRegex") ;
/** Symbol to name the Xerces-J regular expression engine */
public static final Symbol xercesRegex = SystemARQ.allocSymbol("xercesRegex") ;
/**
* Use this Symbol to allow passing additional query parameters to a
* SERVICE <IRI> call.
* Parameters need to be grouped by SERVICE <IRI>,
* a Map<String, Map<String,List<String>>> is assumed.
* The key of the first map is the SERVICE IRI, the value is a Map
* which maps the name of a query string parameters to its values.
*
* @see org.apache.jena.sparql.engine.http.Service
*/
public static final Symbol serviceParams = SystemARQ.allocSymbol("serviceParams") ;
/**
* Control whether SERVICE processing is allowed.
* If the context of the query exexcution contains this,
* and it's set to "false", then SERVICE is not allowed.
*/
public static final Symbol serviceAllowed = Service.serviceAllowed ;
/** If set to true, the parsers will convert undefined prefixes to a URI
* according to the fixup function {@link RiotLib#fixupPrefixes}.
* Normally, unset (which equates to false).
*
* @see RiotLib#isPrefixIRI
*/
public static final Symbol fixupUndefinedPrefixes = SystemARQ.allocSymbol("fixupPrefixes") ;
/**
* A Long value that specifies the number of bindings (or triples for CONSTRUCT queries) to be stored in memory by sort
* operations or hash tables before switching to temporary disk files. The value defaults to -1, which will always
* keep the bindings in memory and never write to temporary files. The amount of memory used will vary based on
* the size of the bindings. If you are retrieving large literal strings, then you may need to lower the value.
* <p/>
* Note that for a complex query, several sort or hash operations might be running in parallel; each one will be
* allowed to retain as many bindings in memory as this value specifies before it starts putting data in temporary
* files. Also, several running sessions could be doing such operations concurrently. Therefore, the total number
* of bindings held in memory could be many times this value; it is necessary to keep this fact in mind when
* choosing the value.
* <p/>
* Operations currently affected by this symbol: <br>
* ORDER BY, SPARQL Update, CONSTRUCT (optionally)
* <p/>
* TODO: Give a reasonable suggested value here. 10,000?
* <p/>
* @see <a href="https://issues.apache.org/jira/browse/JENA-119">JENA-119</a>
*/
// Some possible additions to the list:
// Sort: DISTINCT, merge joins<br>
// Hash table: GROUP BY, MINUS, SERVICE, VALUES, and hash joins <br>
public static final Symbol spillToDiskThreshold = SystemARQ.allocSymbol("spillToDiskThreshold") ;
// Optimizer controls.
/**
* Globally switch the default optimizer on and off :
* Note that storage subsystems may also be applying
* separately controlled optimizations.
*/
public static void enableOptimizer(boolean state)
{
enableOptimizer(ARQ.getContext(), state) ;
}
/**
* Switch the default optimizer on and off for a specific Context.
* Note that storage subsystems may also be applying
* separately controlled optimizations.
*/
public static void enableOptimizer(Context context, boolean state)
{
context.set(ARQ.optimization, state) ;
}
/**
* Context key controlling whether the main query engine applies the
* default optimization transformations.
*/
public static final Symbol optimization = SystemARQ.allocSymbol("optimization") ;
/**
* Context key controlling whether the main query engine flattens simple paths
* (e.g. <tt>?x :p/:q ?z => ?x :p ?.0 . ?.0 ?q ?z</tt>)
* <p>Default is "true"
*/
public static final Symbol optPathFlatten = SystemARQ.allocSymbol("optPathFlatten") ;
/**
* Context key controlling whether the main query engine moves filters to the "best" place.
* Default is "true" - filter placement is done.
*/
public static final Symbol optFilterPlacement = SystemARQ.allocSymbol("optFilterPlacement") ;
/**
* Context key controlling whether to do filter placement within BGP and quad blocks.
* Modies the effect of optFilterPlacement.
* Default is "true" - filter placement is pushed into BGPs.
*/
public static final Symbol optFilterPlacementBGP = SystemARQ.allocSymbol("optFilterPlacementBGP") ;
/**
* Context key controlling whether the main query engine moves filters to the "best" place using
* the more limited and conservative strategy which does not place as many filters
* Must be explicitly set "true" to operate.
* Filter placement, via {@link #optFilterPlacement} must also be active (which it is by default).
* @see #optFilterPlacement
*/
public static final Symbol optFilterPlacementConservative = SystemARQ.allocSymbol("optFilterPlacementConservative") ;
/**
* Context key controlling whether an ORDER BY-LIMIT query is done avoiding total sort using an heap.
* Default is "true" - total sort if avoided by default when ORDER BY is used with LIMIT.
*/
public static final Symbol optTopNSorting = SystemARQ.allocSymbol("optTopNSorting") ;
/**
* Context key controlling whether a DISTINCT-ORDER BY query is done by replacing the distinct with a reduced.
* Default is "true" - the reduced operator does not need to keep a data structure with all previously seen bindings.
*/
public static final Symbol optDistinctToReduced = SystemARQ.allocSymbol("optDistinctToReduced") ;
/**
* Context key controlling whether a DISTINCT-ORDER BY query is done by applying the ORDER BY after the DISTINCT
* when default SPARQL semantics usually mean ORDER BY applies before DISTINCT. This optimization applies only
* in a subset of cases unlike the more general {@link #optDistinctToReduced} optimization.
* <p>
* See {@link TransformOrderByDistinctApplication} for more discussion on exactly when this may apply
* </p>
*/
public static final Symbol optOrderByDistinctApplication = SystemARQ.allocSymbol("optOrderByDistinctApplication");
/**
* Context key controlling whether the standard optimizer applies
* optimizations to equalities in FILTERs.
* This optimization is conservative - it does not take place if
* there is a potential risk of changing query semantics.
*/
public static final Symbol optFilterEquality = SystemARQ.allocSymbol("optFilterEquality") ;
/**
* Context key controlling whether the standard optimizer applies
* optimizations to inequalities in FILTERs
* This optimization is conservative - it does not take place if
* there is a potential risk of changing query semantics
*/
public static final Symbol optFilterInequality = SystemARQ.allocSymbol("optFilterInequality") ;
/**
* Context key controlling whether the standard optimizer applies optimizations to implicit joins in FILTERs.
* This optimization is conservative - it does not take place if there is a potential risk of changing query semantics.
*/
public static final Symbol optFilterImplicitJoin = SystemARQ.allocSymbol("optFilterImplicitJoin");
/**
* Context key controlling whether the standard optimizer applies optimizations to implicit left joins.
* This optimization is conservative - it does not take place if there is a potential risk of changing query semantics.
*/
public static final Symbol optImplicitLeftJoin = SystemARQ.allocSymbol("optImplicitLeftJoin");
/**
* Context key controlling whether the standard optimizer applies constant folding to expressions
* <p>By default, this transformation is applied.
*/
public static final Symbol optExprConstantFolding = SystemARQ.allocSymbol("optExprConstantFolding");
/**
* Context key controlling whether the standard optimizer applies
* optimizations to conjunctions (&&) in filters.
* <p>By default, this transformation is applied.
*/
public static final Symbol optFilterConjunction = SystemARQ.allocSymbol("optFilterConjunction") ;
/**
* Context key controlling whether the standard optimizer applies
* optimizations to IN and NOT IN.
* <p>By default, this transformation is applied.
*/
public static final Symbol optFilterExpandOneOf = SystemARQ.allocSymbol("optFilterExpandOneOf") ;
/**
* Context key controlling whether the standard optimizer applies
* optimizations to disjunctions (||) in filters.
* <p>By default, this transformation is applied.
*/
public static final Symbol optFilterDisjunction = SystemARQ.allocSymbol("optFilterDisjunction") ;
/**
* Context key controlling whether the standard optimizer applies table empty promotion
*/
public static final Symbol optPromoteTableEmpty = SystemARQ.allocSymbol("optPromoteTableEmpty") ;
/**
* Context key controlling whether the standard optimizer applies optimizations to the evaluation
* of joins to favour index joins wherever possible
*/
public static final Symbol optIndexJoinStrategy = SystemARQ.allocSymbol("optIndexJoinStrategy");
/**
* Context key controlling whether the standard optimizer applies optimizations where by some
* assignments may be eliminated/inlined into the operators where their values are used only once
* <p>By default, this transformation is not applied.
*/
public static final Symbol optInlineAssignments = SystemARQ.allocSymbol("optInlineAssignments");
/**
* Context key controlling whether the standard optimizer aggressively inlines assignments whose
* values are used only once into operators where those expressions may be evaluated multiple times e.g. order
* <p>This is modifier to {@link #optInlineAssignments}.
*/
public static final Symbol optInlineAssignmentsAggressive = SystemARQ.allocSymbol("optInlineAssignmentsAggressive");
/**
* Context key controlling whether the standard optimizater applies optimizations to joined BGPs to
* merge them into single BGPs.
* <p>By default, this transformation is applied.
*/
public static final Symbol optMergeBGPs = SystemARQ.allocSymbol("optMergeBGPs");
/**
* Context key controlling whether the standard optimizater applies the optimization
* to combine stacks of (extend) into one compound operation. Ditto (assign).
* <p>By default, this transformation is applied.
*/
public static final Symbol optMergeExtends = SystemARQ.allocSymbol("optMergeExtends");
/**
* Context key controlling whether the standard optimizater applies the optimization
* to reorder basic graph patterns.
* <p>By default, this transformation is NOT applied.
* It is left to the specific engines to decide.
*/
// However, StageGeneratorGeneric does reorder based on partial results.
public static final Symbol optReorderBGP = SystemARQ.allocSymbol("optReorderBGP");
/**
* Context key controlling whether the main query engine processes property functions.
* <p>By default, this is applied.
*/
public static final Symbol propertyFunctions = SystemARQ.allocSymbol("propertyFunctions") ;
/**
* Expression evaluation without extension types (e.g. xsd:date, language tags)
*/
public static final Symbol extensionValueTypes = SystemARQ.allocSymbol("extensionValueTypesExpr") ;
/**
* Generate the ToList operation in the algebra (as ARQ is stream based, ToList is a non-op).
* Default is not to do so. Strict mode will also enable this.
*/
public static final Symbol generateToList = SystemARQ.allocSymbol("generateToList") ;
/** Set strict mode, including expression evaluation */
public static void setStrictMode() { setStrictMode(ARQ.getContext()) ; }
/** Set strict mode for a given Context.
*
* Does not influence expression evaluation because NodeValues
* are controlled globally, not per context.
*/
public static void setStrictMode(Context context)
{
SystemARQ.StrictDateTimeFO = true ;
SystemARQ.ValueExtensions = false ;
SystemARQ.EnableRomanNumerals = false ;
context.set(optimization, false) ;
context.set(hideNonDistiguishedVariables, true) ;
context.set(strictSPARQL, true) ;
context.set(enablePropertyFunctions, false) ;
context.set(extensionValueTypes, false) ;
context.set(constantBNodeLabels, false) ;
context.set(generateToList, true) ;
context.set(regexImpl, xercesRegex) ;
//context.set(filterPlacement, false) ;
}
public static boolean isStrictMode() { return ARQ.getContext().isTrue(strictSPARQL) ; }
/** Set normal mode, including expression evaluation */
public static void setNormalMode() {
SystemARQ.StrictDateTimeFO = false ;
SystemARQ.ValueExtensions = true ;
SystemARQ.EnableRomanNumerals = false ;
setNormalMode(ARQ.getContext()) ;
}
/** Explicitly set the values for normal operation.
* Does not influence expression evaluation.
*/
public static void setNormalMode(Context context)
{
context.set(optimization, true) ;
context.set(hideNonDistiguishedVariables, false) ;
context.set(strictSPARQL, false) ;
context.set(enablePropertyFunctions, true) ;
context.set(extensionValueTypes, true) ;
context.set(constantBNodeLabels, true) ;
context.set(generateToList, false) ;
context.set(regexImpl, javaRegex) ;
}
// ----------------------------------
/** The root package name for ARQ */
public static final String PATH = "org.apache.jena.arq";
static private String metadataLocation = "org/apache/jena/arq/arq-properties.xml" ;
static private Metadata metadata = new Metadata(metadataLocation) ;
/** The product name */
public static final String NAME = "ARQ";
/** The full name of the current ARQ version */
public static final String VERSION = metadata.get(PATH+".version", "unknown") ;
/** The date and time at which this release was built */
public static final String BUILD_DATE = metadata.get(PATH+".build.datetime", "unset") ;
// Initialize now in case other initialization uses getContext().
private static Context globalContext = null ;
/** Ensure things have started - applications do not need call this.
* The method is public so any part of ARQ can call it.
*/
static { JenaSystem.init(); }
public static void init() {
if ( initialized ) {
return ;
}
synchronized(initLock)
{
if ( initialized ) {
JenaSystem.logLifecycle("ARQ.init - skip") ;
return ;
}
initialized = true ;
JenaSystem.logLifecycle("ARQ.init - start") ;
globalContext = defaultSettings() ;
ARQMgt.init() ; // After context and after PATH/NAME/VERSION/BUILD_DATE are set
MappingRegistry.addPrefixMapping(ARQ.arqSymbolPrefix, ARQ.arqParamNS) ;
// This is the pattern for any subsystem to register.
SystemInfo sysInfo = new SystemInfo(ARQ.arqIRI, ARQ.PATH, ARQ.VERSION, ARQ.BUILD_DATE) ;
SystemARQ.registerSubSystem(sysInfo) ;
AssemblerUtils.init() ;
// Register RIOT details here, not earlier, to avoid
// initialization loops with RIOT.init() called directly.
RIOT.register() ;
// Initialise the standard library.
FunctionRegistry.init() ;
AggregateRegistry.init() ;
PropertyFunctionRegistry.init() ;
JenaSystem.logLifecycle("ARQ.init - finish") ;
}
}
/* Side effects */
private static Context defaultSettings()
{
// This must be exeutable before initialization
SystemARQ.StrictDateTimeFO = false ;
SystemARQ.ValueExtensions = true ;
SystemARQ.EnableRomanNumerals = false ;
Context context = new Context() ;
context.unset(optimization) ;
//context.set(hideNonDistiguishedVariables, true) ;
context.set(strictSPARQL, false) ;
context.set(constantBNodeLabels, true) ;
context.set(enablePropertyFunctions, true) ;
context.set(regexImpl, javaRegex) ;
return context ;
}
public static Context getContext()
{
return globalContext ;
}
// Convenience call-throughs
public static void set(Symbol symbol, boolean value) { getContext().set(symbol, value) ; }
public static void setTrue(Symbol symbol) { getContext().setTrue(symbol) ; }
public static void setFalse(Symbol symbol) { getContext().setFalse(symbol) ; }
public static void unset(Symbol symbol) { getContext().unset(symbol) ; }
public static boolean isTrue(Symbol symbol) { return getContext().isTrue(symbol) ; }
public static boolean isFalse(Symbol symbol) { return getContext().isFalse(symbol) ; }
public static boolean isTrueOrUndef(Symbol symbol) { return getContext().isTrueOrUndef(symbol) ; }
public static boolean isFalseOrUndef(Symbol symbol) { return getContext().isFalseOrUndef(symbol) ; }
}