Class RolapEvaluator

  • All Implemented Interfaces:
    Evaluator
    Direct Known Subclasses:
    RolapDependencyTestingEvaluator, RolapProfilingEvaluator

    public class RolapEvaluator
    extends Object
    implements Evaluator
    RolapEvaluator evaluates expressions in a dimensional environment.

    The context contains a member (which may be the default member) for every dimension in the current cube. Certain operations, such as evaluating a calculated member or a tuple, change the current context.

    There are two ways of preserving context.

    First, the push(mondrian.olap.Member[]) method creates a verbatim copy of the evaluator. Use that copy for computations, and any changes of state will be made only to the copy.

    Second, the savepoint() method tells the evaluator to create a checkpoint of its state, and returns an int value that can later be passed to restore(int).

    The savepoint method is recommended for most purposes, because the initial checkpoint is extremely cheap. Each call that modifies state (such as Evaluator.setContext(mondrian.olap.Member)) creates, at a modest cost, an entry on an internal command stack.

    One occasion that you would use push is when creating an iterator, and the iterator needs its own evaluator context, even if the code that created the iterator later reverts the context. In this case, the iterator's constructor should call push.

    Developers note

    Many of the methods in this class are performance-critical. Where possible they are declared 'final' so that the JVM can optimize calls to these methods. If future functionality requires it, the 'final' modifier can be removed and these methods can be overridden.

    Since:
    10 August, 2001
    Author:
    jhyde
    • Field Detail

      • cellReader

        protected mondrian.rolap.CellReader cellReader
      • root

        protected final mondrian.rolap.RolapEvaluatorRoot root
      • aggregationLists

        protected final List<List<List<Member>>> aggregationLists
        List of lists of tuples or members, rarely used, but overrides the ordinary dimensional context if set when a cell value comes to be evaluated.
    • Constructor Detail

      • RolapEvaluator

        protected RolapEvaluator​(mondrian.rolap.RolapEvaluatorRoot root,
                                 RolapEvaluator parent,
                                 List<List<Member>> aggregationList)
        Creates a non-root evaluator.
        Parameters:
        root - Root context for stack of evaluators (contains information which does not change during the evaluation)
        parent - Parent evaluator, not null
        aggregationList - List of tuples to add to aggregation context, or null
      • RolapEvaluator

        public RolapEvaluator​(mondrian.rolap.RolapEvaluatorRoot root)
        Creates a root evaluator.
        Parameters:
        root - Shared context between this evaluator and its children
    • Method Detail

      • getActiveNativeExpansions

        public Set<Exp> getActiveNativeExpansions()
        Set of expressions actively being expanded. Prevents infinite cycle of expansions.
        Returns:
        Mutable set of expressions being expanded
      • getMeasureCube

        public RolapCube getMeasureCube()
        Description copied from interface: Evaluator
        Returns the base (non-virtual) cube that the current measure in the context belongs to.
        Specified by:
        getMeasureCube in interface Evaluator
        Returns:
        Cube
      • needToReturnNullForUnrelatedDimension

        public boolean needToReturnNullForUnrelatedDimension​(Member[] members)
        Description copied from interface: Evaluator
        If IgnoreMeasureForNonJoiningDimension is set to true and one or more members are on unrelated dimension for the measure in current context then returns true.

        You must not call this method unless Evaluator.mightReturnNullForUnrelatedDimension() has returned true.

        Specified by:
        needToReturnNullForUnrelatedDimension in interface Evaluator
        Parameters:
        members - Dimensions for the members need to be checked whether related or unrelated
        Returns:
        boolean
      • nativeEnabled

        public boolean nativeEnabled()
        Description copied from interface: Evaluator
        Returns whether native evaluation is enabled in this context.
        Specified by:
        nativeEnabled in interface Evaluator
        Returns:
        whether native evaluation is enabled in this context
      • currentIsEmpty

        public boolean currentIsEmpty()
        Description copied from interface: Evaluator
        Returns whether the current context is an empty cell.
        Specified by:
        currentIsEmpty in interface Evaluator
        Returns:
        Whether the current context is an empty cell
      • getPreviousContext

        public Member getPreviousContext​(Hierarchy hierarchy)
        Description copied from interface: Evaluator
        Returns the member that was the current evaluation context for a particular hierarchy before the most recent change in context.
        Specified by:
        getPreviousContext in interface Evaluator
        Parameters:
        hierarchy - Hierarchy
        Returns:
        Previous context member for given hierarchy
      • getTiming

        public final QueryTiming getTiming()
        Description copied from interface: Evaluator
        Returns the query timing context for this execution.
        Specified by:
        getTiming in interface Evaluator
        Returns:
        query timing context
      • savepoint

        public final int savepoint()
        Description copied from interface: Evaluator
        Creates a savepoint encapsulating the current state of the evalutor. You can restore the evaluator to this state by calling Evaluator.restore(int) with the value returned by this method.

        This method is typically called before evaluating an expression which is known to corrupt the evaluation context.

        Multiple savepoints may be active at the same time for the same evaluator. And, it is allowable to restore to the save savepoint more than once (or not at all). However, when you have rolled back to a particular savepoint you may not restore to a later savepoint.

        Specified by:
        savepoint in interface Evaluator
        Returns:
        Evaluator with each given member overriding the state of the current Evaluator for its hierarchy
      • setNativeEnabled

        public final void setNativeEnabled​(boolean nativeEnabled)
        Description copied from interface: Evaluator
        Sets whether native evaluation should be used.
        Specified by:
        setNativeEnabled in interface Evaluator
        Parameters:
        nativeEnabled - Whether native evaluation should be used
      • getLogger

        protected final org.apache.logging.log4j.Logger getLogger()
      • getMembers

        public final Member[] getMembers()
        Description copied from interface: Evaluator
        Returns an array of the members which make up the current context.
        Specified by:
        getMembers in interface Evaluator
      • getNonAllMembers

        public final Member[] getNonAllMembers()
        Description copied from interface: Evaluator
        Returns an array of the non-All members which make up the current context.

        Notes:

        • The 0th element is a measure, but otherwise the order of the members is unspecified.
        • No hierarchy occurs more than once.
        • In rare circumstances, some of the members may be an 'All' member.
        • The list may contain calculated members.
        Specified by:
        getNonAllMembers in interface Evaluator
      • getQuery

        public final Query getQuery()
        Description copied from interface: Evaluator
        Returns the current query.
        Specified by:
        getQuery in interface Evaluator
      • getDepth

        public final int getDepth()
        Description copied from interface: Evaluator
        Obsolete method.
        Specified by:
        getDepth in interface Evaluator
      • getQueryStartTime

        public Date getQueryStartTime()
        Description copied from interface: Evaluator
        Returns the start time of the current query.
        Specified by:
        getQueryStartTime in interface Evaluator
      • getDialect

        public Dialect getDialect()
      • push

        public final RolapEvaluator push​(Member[] members)
        Description copied from interface: Evaluator
        Creates a new Evaluator with each given member overriding the context of the current Evaluator for its hierarchy. Other hierarchies retain the same context as this Evaluator.

        In mondrian-3.3 and later, a more efficient way to save the state of an evaluator is to call Evaluator.savepoint() followed by Evaluator.restore(int). We recommend using those methods.

        Specified by:
        push in interface Evaluator
        Parameters:
        members - Array of members to add to the context
        Returns:
        Evaluator with each given member overriding the state of the current Evaluator for its hierarchy
      • push

        public final RolapEvaluator push​(Member member)
        Description copied from interface: Evaluator
        Creates a new Evaluator with the same context except for one member.

        This method is typically called before evaluating an expression which may corrupt the evaluation context.

        In mondrian-3.3 and later, a more efficient way to save the state of an evaluator is to call Evaluator.savepoint() followed by Evaluator.restore(int). We recommend using those methods.

        Specified by:
        push in interface Evaluator
        Parameters:
        member - Member to add to the context
        Returns:
        Evaluator with each given member overriding the state of the current Evaluator for its hierarchy
      • push

        public final Evaluator push​(boolean nonEmpty)
        Description copied from interface: Evaluator
        Creates a new evaluator with the same state except nonEmpty property

        In mondrian-3.3 and later, a more efficient way to save the state of an evaluator is to call Evaluator.savepoint() followed by Evaluator.restore(int). We recommend using those methods.

        Specified by:
        push in interface Evaluator
      • push

        public final Evaluator push​(boolean nonEmpty,
                                    boolean nativeEnabled)
        Description copied from interface: Evaluator
        Creates a new evaluator with the same state except nonEmpty and nativeEnabled properties.

        In mondrian-3.3 and later, a more efficient way to save the state of an evaluator is to call Evaluator.savepoint() followed by Evaluator.restore(int). We recommend using those methods.

        Specified by:
        push in interface Evaluator
      • push

        public final RolapEvaluator push()
        Description copied from interface: Evaluator
        Creates a new Evaluator with the same context as this evaluator.

        This method is typically called before evaluating an expression which may corrupt the evaluation context.

        In mondrian-3.3 and later, a more efficient way to save the state of an evaluator is to call Evaluator.savepoint() followed by Evaluator.restore(int). We recommend using those methods most of the time.

        However, it makes sense to use this method in the constructor of an iterator. It allows the iterator to modify its evaluation context without affecting the evaluation context of the calling code. This behavior cannot be achieved using savepoint.

        Specified by:
        push in interface Evaluator
        Returns:
        Evaluator with each given member overriding the state of the current Evaluator for its hierarchy
      • _push

        protected RolapEvaluator _push​(List<List<Member>> aggregationList)
        Creates a clone of the current validator.
        Parameters:
        aggregationList - List of tuples to add to aggregation context, or null
      • restore

        public final void restore​(int savepoint)
        Description copied from interface: Evaluator
        Restores previous evaluator.
        Specified by:
        restore in interface Evaluator
        Parameters:
        savepoint - Savepoint returned by Evaluator.savepoint()
      • pushAggregation

        public final Evaluator pushAggregation​(List<List<Member>> list)
        Description copied from interface: Evaluator
        Returns a new Aggregator whose aggregation context adds a given list of tuples, and whose evaluation context is the same as this Aggregator.
        Specified by:
        pushAggregation in interface Evaluator
        Parameters:
        list - List of tuples
        Returns:
        Aggregator with list added to its aggregation context
      • equals

        public final boolean equals​(Object obj)
        Returns true if the other object is a RolapEvaluator with identical context.
        Overrides:
        equals in class Object
      • hashCode

        public final int hashCode()
        Overrides:
        hashCode in class Object
      • setSlicerContext

        public final void setSlicerContext​(List<Member> members,
                                           Map<Hierarchy,​Set<Member>> membersByHierarchy)
        Adds a slicer member to the evaluator context, and remember it as part of the slicer. The slicer members are passed onto derived evaluators so that functions using those evaluators can choose to ignore the slicer members. One such function is CrossJoin emptiness check.
        Parameters:
        members - members in slicer
        membersByHierarchy - members in slicer by hierarchy
      • getSlicerMembers

        public final List<Member> getSlicerMembers()
        Return the list of slicer members in the current evaluator context.
        Returns:
        slicerMembers
      • setSlicerTuples

        public final void setSlicerTuples​(TupleList tuples)
        Sets the slicer tuple object, used later by native evaluation and non-empty crossjoins.
        Parameters:
        tuples - slicer
      • getSlicerTuples

        public final TupleList getSlicerTuples()
        Return the list of compound slicer tuples
      • isDisjointSlicerTuple

        public boolean isDisjointSlicerTuple()
      • isMultiLevelSlicerTuple

        public boolean isMultiLevelSlicerTuple()
      • getOptimizedSlicerTuples

        public final TupleList getOptimizedSlicerTuples​(RolapCube baseCube)
        Returns an optimized list of tuples related to the slicer based on the current evaluator. This function removes overridden compound slicer members from the tuple list. TODO: Add Virtual Cube test cases, demonstrating unrelated dimensions. TODO: Test various Tuple List sizes - tuples sizes that are bigger and smaller than list size
        Parameters:
        baseCube - if this is a virtual cube, remove the unrelated tuples from the slicer.
        Returns:
        optimized slicer tuple list
      • setContext

        public final Member setContext​(Member member)
        Description copied from interface: Evaluator
        Makes member the current member of its hierarchy.
        Specified by:
        setContext in interface Evaluator
        Parameters:
        member - New member
        Returns:
        Previous member of this hierarchy
      • setContext

        public final void setContext​(Member member,
                                     boolean safe)
        Description copied from interface: Evaluator
        Makes member the current member of its hierarchy.

        If safe, checks whether this is the first time that a member of this hierarchy has been changed since Evaluator.savepoint() was called. If so, saves the previous member. If safe is false, never saves the previous member.

        Use safe = false only if you are sure that the context has been set before. For example,

        int n = 0;
        for (Member member : members) {
          evaluator.setContext(member, n++ > 0);
        }
        Specified by:
        setContext in interface Evaluator
        Parameters:
        member - New member
        safe - Whether to store the member of this hierarchy that was current last time that Evaluator.savepoint() was called.
      • setContext

        public final void setContext​(List<Member> memberList)
        Description copied from interface: Evaluator
        Sets the context to a list of members.

        Equivalent to

        for (Member member : memberList) {
          setContext(member);
        }
        Specified by:
        setContext in interface Evaluator
        Parameters:
        memberList - List of members
      • setContext

        public final void setContext​(List<Member> memberList,
                                     boolean safe)
        Description copied from interface: Evaluator
        Sets the context to a list of members, optionally skipping the check whether it is necessary to store the previous member of each hierarchy.

        Equivalent to

        for (Member member : memberList) {
          setContext(member, safe);
        }
        Specified by:
        setContext in interface Evaluator
        Parameters:
        memberList - List of members
        safe - Whether to store the member of each hierarchy that was current last time that Evaluator.savepoint() was called.
      • setContext

        public final void setContext​(Member[] members)
        Description copied from interface: Evaluator
        Sets the context to an array of members.

        Equivalent to

        for (Member member : memberList) {
          setContext(member);
        }
        Specified by:
        setContext in interface Evaluator
        Parameters:
        members - Array of members
      • setContext

        public final void setContext​(Member[] members,
                                     boolean safe)
        Description copied from interface: Evaluator
        Sets the context to an array of members, optionally skipping the check whether it is necessary to store the previous member of each hierarchy.

        Equivalent to

        for (Member member : memberList) {
          setContext(member, safe);
        }
        Specified by:
        setContext in interface Evaluator
        Parameters:
        members - Array of members
        safe - Whether to store the member of each hierarchy that was current last time that Evaluator.savepoint() was called.
      • evaluateCurrent

        public final Object evaluateCurrent()
        Description copied from interface: Evaluator
        Calculates and returns the value of the cell at the current context.
        Specified by:
        evaluateCurrent in interface Evaluator
      • getProperty

        public final Object getProperty​(String name,
                                        Object defaultValue)
        Description copied from interface: Evaluator
        Retrieves the value of property name. If more than one member in the current context defines that property, the one with the highest solve order has precedence.

        If the property is not defined, default value is returned.

        Specified by:
        getProperty in interface Evaluator
      • getFormatString

        public final String getFormatString()
        Returns the format string for this cell. This is computed by evaluating the format expression in the current context, and therefore different cells may have different format strings.
        Specified by:
        getFormatString in interface Evaluator
      • format

        public final String format​(Object o)
        Description copied from interface: Evaluator
        Formats a value as a string according to the current context's format.
        Specified by:
        format in interface Evaluator
      • format

        public final String format​(Object o,
                                   String formatString)
        Description copied from interface: Evaluator
        Formats a value as a string according to the current context's format, using a given format string.
        Specified by:
        format in interface Evaluator
      • getCachedResult

        public final Object getCachedResult​(ExpCacheDescriptor cacheDescriptor)
        Description copied from interface: Evaluator
        Simple caching of the result of an Exp. The key for the cache consists of all members of the current context that exp depends on. Members of independent hierarchies are not part of the key.
        Specified by:
        getCachedResult in interface Evaluator
        See Also:
        Calc.dependsOn(Hierarchy)
      • clearExpResultCache

        public final void clearExpResultCache​(boolean clearValidResult)
      • isNonEmpty

        public final boolean isNonEmpty()
        Description copied from interface: Evaluator
        Returns true for an axis that is NON EMPTY.

        May be used by expression evaluators to optimize their result. For example, a top-level crossjoin may be optimized by removing all non-empty set elements before performing the crossjoin. This is possible because of the identity

        nonempty(crossjoin(a, b)) == nonempty(crossjoin(nonempty(a), nonempty(b));
        Specified by:
        isNonEmpty in interface Evaluator
      • setNonEmpty

        public final void setNonEmpty​(boolean nonEmpty)
        Description copied from interface: Evaluator
        Sets whether an expression evaluation should filter out empty cells. Allows expressions to modify non empty flag to evaluate their children.
        Specified by:
        setNonEmpty in interface Evaluator
      • newEvalException

        public final RuntimeException newEvalException​(Object context,
                                                       String s)
        Description copied from interface: Evaluator
        Creates an exception which indicates that an error has occurred during the runtime evaluation of a function. The caller should then throw that exception.
        Specified by:
        newEvalException in interface Evaluator
      • getNamedSetEvaluator

        public final Evaluator.NamedSetEvaluator getNamedSetEvaluator​(NamedSet namedSet,
                                                                      boolean create)
        Description copied from interface: Evaluator
        Returns an evaluator for a named set.
        Specified by:
        getNamedSetEvaluator in interface Evaluator
        Parameters:
        namedSet - Named set
        create - Whether to create evaluator if not found
        Returns:
        Evaluator of named set
      • getSetEvaluator

        public final Evaluator.SetEvaluator getSetEvaluator​(Exp exp,
                                                            boolean create)
        Description copied from interface: Evaluator
        Returns an evaluator for a set.
        Specified by:
        getSetEvaluator in interface Evaluator
        Parameters:
        exp - Expression
        create - Whether to create evaluator if not found
        Returns:
        Evaluator of named set
      • getMissCount

        public final int getMissCount()
        Description copied from interface: Evaluator
        Returns the number of times that this evaluator has told a lie when retrieving cell values.
        Specified by:
        getMissCount in interface Evaluator
      • getIterationLength

        public final int getIterationLength()
        Specified by:
        getIterationLength in interface Evaluator
        Returns:
        the iteration length of the current context
      • setIterationLength

        public final void setIterationLength​(int iterationLength)
        Description copied from interface: Evaluator
        Sets the iteration length for the current evaluator context
        Specified by:
        setIterationLength in interface Evaluator
        Parameters:
        iterationLength - length to be set
      • isEvalAxes

        public final boolean isEvalAxes()
        Specified by:
        isEvalAxes in interface Evaluator
        Returns:
        true if evaluating axes
      • setEvalAxes

        public final void setEvalAxes​(boolean evalAxes)
        Description copied from interface: Evaluator
        Indicate whether the evaluator is evaluating the axes
        Specified by:
        setEvalAxes in interface Evaluator
        Parameters:
        evalAxes - true if evaluating axes
      • shouldIgnoreUnrelatedDimensions

        public boolean shouldIgnoreUnrelatedDimensions()
        Checks if unrelated dimensions to the measure in the current context should be ignored.
        Specified by:
        shouldIgnoreUnrelatedDimensions in interface Evaluator
        Returns:
        boolean