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/*
 * 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
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package org.apache.cassandra.cql3.selection;

import java.util.*;
import java.util.function.Predicate;
import java.util.stream.Collectors;

import org.apache.cassandra.cql3.*;
import org.apache.cassandra.cql3.functions.*;
import org.apache.cassandra.cql3.selection.Selector.Factory;
import org.apache.cassandra.db.marshal.*;
import org.apache.cassandra.exceptions.InvalidRequestException;
import org.apache.cassandra.schema.ColumnMetadata;
import org.apache.cassandra.schema.TableMetadata;
import org.apache.cassandra.utils.Pair;

import static org.apache.cassandra.cql3.selection.SelectorFactories.createFactoriesAndCollectColumnDefinitions;
import static org.apache.cassandra.cql3.statements.RequestValidations.invalidRequest;

public interface Selectable extends AssignmentTestable
{
    public Selector.Factory newSelectorFactory(TableMetadata table, AbstractType expectedType, List defs, VariableSpecifications boundNames);

    /**
     * The type of the {@code Selectable} if it can be infered.
     *
     * @param keyspace the keyspace on which the statement for which this is a
     * {@code Selectable} is on.
     * @return the type of this {@code Selectable} if inferrable, or {@code null}
     * otherwise (for instance, the type isn't inferable for a bind marker. Even for
     * literals, the exact type is not inferrable since they are valid for many
     * different types and so this will return {@code null} too).
     */
    public AbstractType getExactTypeIfKnown(String keyspace);

    /**
     * Checks if this {@code Selectable} select columns matching the specified predicate.
     * @return {@code true} if this {@code Selectable} select columns matching the specified predicate,
     * {@code false} otherwise.
     */
    public boolean selectColumns(Predicate predicate);

    /**
     * Checks if the specified Selectables select columns matching the specified predicate.
     * @param selectables the selectables to check.
     * @return {@code true} if the specified Selectables select columns matching the specified predicate,
      {@code false} otherwise.
     */
    public static boolean selectColumns(List selectables, Predicate predicate)
    {
        for (Selectable selectable : selectables)
        {
            if (selectable.selectColumns(predicate))
                return true;
        }
        return false;
    }

    /**
     * Checks if any processing is performed on the selected columns, {@code false} otherwise.
     * @return {@code true} if any processing is performed on the selected columns, {@code false} otherwise.
     */
    public default boolean processesSelection()
    {
        // ColumnMetadata is the only case that returns false (if the column is not masked) and overrides this
        return true;
    }

    // Term.Raw overrides this since some literals can be WEAKLY_ASSIGNABLE
    default public TestResult testAssignment(String keyspace, ColumnSpecification receiver)
    {
        AbstractType type = getExactTypeIfKnown(keyspace);
        return type == null ? TestResult.NOT_ASSIGNABLE : type.testAssignment(keyspace, receiver);
    }

    @Override
    public default AbstractType getCompatibleTypeIfKnown(String keyspace)
    {
        return getExactTypeIfKnown(keyspace);
    }

    default int addAndGetIndex(ColumnMetadata def, List l)
    {
        int idx = l.indexOf(def);
        if (idx < 0)
        {
            idx = l.size();
            l.add(def);
        }
        return idx;
    }

    default ColumnSpecification specForElementOrSlice(Selectable selected, ColumnSpecification receiver, CollectionType.Kind kind, String selectionType)
    {
        switch (kind)
        {
            case LIST: throw new InvalidRequestException(String.format("%s selection is only allowed on sets and maps, but %s is a list", selectionType, selected));
            case SET: return Sets.valueSpecOf(receiver);
            case MAP: return Maps.keySpecOf(receiver);
            default: throw new AssertionError();
        }
    }

    public interface Raw
    {
        public Selectable prepare(TableMetadata table);
    }

    public static class WithTerm implements Selectable
    {
        /**
         * The names given to unamed bind markers found in selection. In selection clause, we often don't have a good
         * name for bind markers, typically if you have:
         *   SELECT (int)? FROM foo;
         * there isn't a good name for that marker. So we give the same name to all the markers. Note that we could try
         * to differenciate the names by using some increasing number in the name (so [selection_1], [selection_2], ...)
         * but it's actually not trivial to do in the current code and it's not really more helpful since if users wants
         * to bind by position (which they will have to in this case), they can do so at the driver level directly. And
         * so we don't bother.
         * Note that users should really be using named bind markers if they want to be able to bind by names.
         */
        private static final ColumnIdentifier bindMarkerNameInSelection = new ColumnIdentifier("[selection]", true);

        private final Term.Raw rawTerm;

        public WithTerm(Term.Raw rawTerm)
        {
            this.rawTerm = rawTerm;
        }

        @Override
        public TestResult testAssignment(String keyspace, ColumnSpecification receiver)
        {
            return rawTerm.testAssignment(keyspace, receiver);
        }

        public Selector.Factory newSelectorFactory(TableMetadata table, AbstractType expectedType, List defs, VariableSpecifications boundNames) throws InvalidRequestException
        {
            /*
             * expectedType will be null if we have no constraint on what the type should be. For instance, if this term is a bind marker:
             *   - it will be null if we do "SELECT ? FROM foo"
             *   - it won't be null (and be LongType) if we do "SELECT bigint_as_blob(?) FROM foo" because the function constrain it.
             *
             * In the first case, we have to error out: we need to infer the type of the metadata of a SELECT at preparation time, which we can't
             * here (users will have to do "SELECT (varint)? FROM foo" for instance).
             * But in the 2nd case, we're fine and can use the expectedType to "prepare" the bind marker/collect the bound type.
             *
             * Further, the term might not be a bind marker, in which case we sometimes can default to some most-general type. For instance, in
             *   SELECT 3 FROM foo
             * we'll just default the type to 'varint' as that's the most generic type for the literal '3' (this is mostly for convenience, the query
             * is not terribly useful in practice and use can force the type as for the bind marker case through "SELECT (int)3 FROM foo").
             * But note that not all literals can have such default type. For instance, there is no way to infer the type of a UDT literal in a vacuum,
             * and so we simply error out if we have something like:
             *   SELECT { foo: 'bar' } FROM foo
             *
             * Lastly, note that if the term is a terminal literal, we don't have to check it's compatibility with 'expectedType' as any incompatibility
             * would have been found at preparation time.
             */
            AbstractType type = getExactTypeIfKnown(table.keyspace);
            if (type == null)
            {
                type = expectedType;
                if (type == null)
                    throw new InvalidRequestException("Cannot infer type for term " + this + " in selection clause (try using a cast to force a type)");
            }

            // The fact we default the name to "[selection]" inconditionally means that any bind marker in a
            // selection will have this name. Which isn't terribly helpful, but it's unclear how to provide
            // something a lot more helpful and in practice user can bind those markers by position or, even better,
            // use bind markers.
            Term term = rawTerm.prepare(table.keyspace, new ColumnSpecification(table.keyspace, table.name, bindMarkerNameInSelection, type));
            term.collectMarkerSpecification(boundNames);
            return TermSelector.newFactory(rawTerm.getText(), term, type);
        }

        @Override
        public AbstractType getExactTypeIfKnown(String keyspace)
        {
            return rawTerm.getExactTypeIfKnown(keyspace);
        }

        @Override
        public AbstractType getCompatibleTypeIfKnown(String keyspace)
        {
            return rawTerm.getCompatibleTypeIfKnown(keyspace);
        }

        @Override
        public boolean selectColumns(Predicate predicate)
        {
            return false;
        }

        @Override
        public String toString()
        {
            return rawTerm.getText();
        }

        public static class Raw implements Selectable.Raw
        {
            private final Term.Raw term;

            public Raw(Term.Raw term)
            {
                this.term = term;
            }

            public Selectable prepare(TableMetadata table)
            {
                return new WithTerm(term);
            }
        }
    }

    public static class WritetimeOrTTL implements Selectable
    {
        // The order of the variants in the Kind enum matters as they are used in ser/deser
        public enum Kind
        {
            TTL("ttl", Int32Type.instance),
            WRITE_TIME("writetime", LongType.instance),
            MAX_WRITE_TIME("maxwritetime", LongType.instance); // maxwritetime is available after Cassandra 4.1 (exclusive)

            public final String name;
            public final AbstractType returnType;

            public static Kind fromOrdinal(int ordinal)
            {
                return values()[ordinal];
            }

            Kind(String name, AbstractType returnType)
            {
                this.name = name;
                this.returnType = returnType;
            }

            public boolean aggregatesMultiCell()
            {
                return this == MAX_WRITE_TIME;
            }
        }

        public final ColumnMetadata column;
        public final Selectable selectable;
        public final Kind kind;

        public WritetimeOrTTL(ColumnMetadata column, Selectable selectable, Kind kind)
        {
            this.column = column;
            this.selectable = selectable;
            this.kind = kind;
        }

        @Override
        public String toString()
        {
            return kind.name + "(" + selectable + ")";
        }

        public Selector.Factory newSelectorFactory(TableMetadata table,
                                                   AbstractType expectedType,
                                                   List defs,
                                                   VariableSpecifications boundNames)
        {
            if (column.isPrimaryKeyColumn())
                throw new InvalidRequestException(
                        String.format("Cannot use selection function %s on PRIMARY KEY part %s",
                                      kind.name,
                                      column.name));

            Selector.Factory factory = selectable.newSelectorFactory(table, expectedType, defs, boundNames);
            boolean isMultiCell = factory.getColumnSpecification(table).type.isMultiCell();

            return WritetimeOrTTLSelector.newFactory(factory, addAndGetIndex(column, defs), kind, isMultiCell);
        }

        @Override
        public AbstractType getExactTypeIfKnown(String keyspace)
        {
            AbstractType type = kind.returnType;
            return column.type.isMultiCell() && !kind.aggregatesMultiCell() ? ListType.getInstance(type, false) : type;
        }

        @Override
        public boolean selectColumns(Predicate predicate)
        {
            return selectable.selectColumns(predicate);
        }

        public static class Raw implements Selectable.Raw
        {
            private final Selectable.RawIdentifier column;
            private final Selectable.Raw selected;
            private final Kind kind;

            public Raw(Selectable.RawIdentifier column, Selectable.Raw selected, Kind kind)
            {
                this.column = column;
                this.selected = selected;
                this.kind = kind;
            }

            @Override
            public WritetimeOrTTL prepare(TableMetadata table)
            {
                return new WritetimeOrTTL((ColumnMetadata) column.prepare(table), selected.prepare(table), kind);
            }
        }
    }

    public static class WithFunction implements Selectable
    {
        public final Function function;
        public final List args;

        public WithFunction(Function function, List args)
        {
            this.function = function;
            this.args = args;
        }

        @Override
        public String toString()
        {
            return function.columnName(args.stream().map(Object::toString).collect(Collectors.toList()));
        }

        public Selector.Factory newSelectorFactory(TableMetadata table, AbstractType expectedType, List defs, VariableSpecifications boundNames)
        {
            SelectorFactories factories = SelectorFactories.createFactoriesAndCollectColumnDefinitions(args, function.argTypes(), table, defs, boundNames);
            return AbstractFunctionSelector.newFactory(function, factories);
        }

        @Override
        public boolean selectColumns(Predicate predicate)
        {
            return Selectable.selectColumns(args, predicate);
        }

        public AbstractType getExactTypeIfKnown(String keyspace)
        {
            return function.returnType();
        }

        public static class Raw implements Selectable.Raw
        {
            private final FunctionName functionName;
            private final List args;

            public Raw(FunctionName functionName, List args)
            {
                this.functionName = functionName;
                this.args = args;
            }

            public static Raw newCountRowsFunction()
            {
                return new Raw(AggregateFcts.countRowsFunction.name(),
                               Collections.emptyList());
            }

            public static Raw newOperation(char operator, Selectable.Raw left, Selectable.Raw right)
            {
                return new Raw(OperationFcts.getFunctionNameFromOperator(operator),
                               Arrays.asList(left, right));
            }

            public static Raw newNegation(Selectable.Raw arg)
            {
                return new Raw(FunctionName.nativeFunction(OperationFcts.NEGATION_FUNCTION_NAME),
                               Collections.singletonList(arg));
            }

            @Override
            public Selectable prepare(TableMetadata table)
            {
                List preparedArgs = new ArrayList<>(args.size());
                for (Selectable.Raw arg : args)
                    preparedArgs.add(arg.prepare(table));

                FunctionName name = functionName;
                // COUNT(x) is equivalent to COUNT(*) for any non-null term x (since count(x) don't care about its
                // argument outside of check for nullness) and for backward compatibilty we want to support COUNT(1),
                // but we actually have COUNT(x) method for every existing (simple) input types so currently COUNT(1)
                // will throw as ambiguous (since 1 works for any type). So we have to special case COUNT.
                if (functionName.equalsNativeFunction(FunctionName.nativeFunction("count"))
                        && preparedArgs.size() == 1
                        && (preparedArgs.get(0) instanceof WithTerm)
                        && (((WithTerm)preparedArgs.get(0)).rawTerm instanceof Constants.Literal))
                {
                    // Note that 'null' isn't a Constants.Literal
                    name = AggregateFcts.countRowsFunction.name();
                    preparedArgs = Collections.emptyList();
                }

                Function fun = FunctionResolver.get(table.keyspace, name, preparedArgs, table.keyspace, table.name, null);

                if (fun == null)
                    throw new InvalidRequestException(String.format("Unknown function '%s'", functionName));

                if (fun.returnType() == null)
                    throw new InvalidRequestException(String.format("Unknown function %s called in selection clause", functionName));

                return new WithFunction(fun, preparedArgs);
            }
        }
    }

    public static class WithCast implements Selectable
    {
        private final CQL3Type type;
        private final Selectable arg;

        public WithCast(Selectable arg, CQL3Type type)
        {
            this.arg = arg;
            this.type = type;
        }

        @Override
        public String toString()
        {
            return String.format("cast(%s as %s)", arg, type.toString().toLowerCase());
        }

        public Selector.Factory newSelectorFactory(TableMetadata table, AbstractType expectedType, List defs, VariableSpecifications boundNames)
        {
            List args = Collections.singletonList(arg);
            SelectorFactories factories = SelectorFactories.createFactoriesAndCollectColumnDefinitions(args, null, table, defs, boundNames);

            Selector.Factory factory = factories.get(0);

            // If the user is trying to cast a type on its own type we simply ignore it.
            if (type.getType().equals(factory.getReturnType()))
                return factory;

            FunctionName name = FunctionName.nativeFunction(CastFcts.getFunctionName(type));
            Function fun = FunctionResolver.get(table.keyspace, name, args, table.keyspace, table.name, null);

            if (fun == null)
            {
                    throw new InvalidRequestException(String.format("%s cannot be cast to %s",
                                                                    defs.get(0).name,
                                                                    type));
            }
            return AbstractFunctionSelector.newFactory(fun, factories);
        }

        public AbstractType getExactTypeIfKnown(String keyspace)
        {
            return type.getType();
        }

        @Override
        public boolean selectColumns(Predicate predicate)
        {
            return arg.selectColumns(predicate);
        }

        public static class Raw implements Selectable.Raw
        {
            private final CQL3Type type;
            private final Selectable.Raw arg;

            public Raw(Selectable.Raw arg, CQL3Type type)
            {
                this.arg = arg;
                this.type = type;
            }

            public WithCast prepare(TableMetadata table)
            {
                return new WithCast(arg.prepare(table), type);
            }
        }
    }

    /**
     * Represents the selection of the field of a UDT (eg. t.f).
     */
    public static class WithFieldSelection implements Selectable
    {
        public final Selectable selected;
        public final FieldIdentifier field;

        public WithFieldSelection(Selectable selected, FieldIdentifier field)
        {
            this.selected = selected;
            this.field = field;
        }

        @Override
        public String toString()
        {
            return String.format("%s.%s", selected, field);
        }

        public Selector.Factory newSelectorFactory(TableMetadata table, AbstractType expectedType, List defs, VariableSpecifications boundNames)
        {
            AbstractType expectedUdtType = null;

            // If the UDT is between parentheses, we know that it is not a tuple with a single element.
            if (selected instanceof BetweenParenthesesOrWithTuple)
            {
                BetweenParenthesesOrWithTuple betweenParentheses = (BetweenParenthesesOrWithTuple) selected;
                expectedUdtType = betweenParentheses.selectables.get(0).getExactTypeIfKnown(table.keyspace);
            }

            Selector.Factory factory = selected.newSelectorFactory(table, expectedUdtType, defs, boundNames);
            AbstractType type = factory.getReturnType();
            if (!type.isUDT())
            {
                throw new InvalidRequestException(
                        String.format("Invalid field selection: %s of type %s is not a user type",
                                selected,
                                type.asCQL3Type()));
            }

            UserType ut = (UserType) type;
            int fieldIndex = ut.fieldPosition(field);
            if (fieldIndex == -1)
            {
                throw new InvalidRequestException(String.format("%s of type %s has no field %s",
                        selected, type.asCQL3Type(), field));
            }

            return FieldSelector.newFactory(ut, fieldIndex, factory);
        }

        public AbstractType getExactTypeIfKnown(String keyspace)
        {
            AbstractType selectedType = selected.getExactTypeIfKnown(keyspace);
            if (selectedType == null || !(selectedType instanceof UserType))
                return null;

            UserType ut = (UserType) selectedType;
            int fieldIndex = ut.fieldPosition(field);
            if (fieldIndex == -1)
                return null;

            return ut.fieldType(fieldIndex);
        }

        @Override
        public boolean selectColumns(Predicate predicate)
        {
            return selected.selectColumns(predicate);
        }

        public static class Raw implements Selectable.Raw
        {
            private final Selectable.Raw selected;
            private final FieldIdentifier field;

            public Raw(Selectable.Raw selected, FieldIdentifier field)
            {
                this.selected = selected;
                this.field = field;
            }

            public WithFieldSelection prepare(TableMetadata table)
            {
                return new WithFieldSelection(selected.prepare(table), field);
            }
        }
    }

    /**
     * {@code Selectable} for {@code Selectable} between parentheses or tuples.
     * 

The parser cannot differentiate between a single element between parentheses or a single element tuple. * By consequence, we are forced to wait until the type is known to be able to differentiate them.

*/ public static class BetweenParenthesesOrWithTuple implements Selectable { /** * The tuple elements or the element between the parentheses */ private final List selectables; public BetweenParenthesesOrWithTuple(List selectables) { this.selectables = selectables; } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { if (selectables.size() == 1 && !receiver.type.isTuple()) return selectables.get(0).testAssignment(keyspace, receiver); return Tuples.testTupleAssignment(receiver, selectables); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { AbstractType type = getExactTypeIfKnown(cfm.keyspace); if (type == null) { type = expectedType; if (type == null) throw invalidRequest("Cannot infer type for term %s in selection clause (try using a cast to force a type)", this); } if (selectables.size() == 1 && !type.isTuple()) return newBetweenParenthesesSelectorFactory(cfm, expectedType, defs, boundNames); return newTupleSelectorFactory(cfm, (TupleType) type, defs, boundNames); } private Factory newBetweenParenthesesSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { Selectable selectable = selectables.get(0); final Factory factory = selectable.newSelectorFactory(cfm, expectedType, defs, boundNames); return new ForwardingFactory() { protected Factory delegate() { return factory; } protected String getColumnName() { return String.format("(%s)", factory.getColumnName()); } }; } private Factory newTupleSelectorFactory(TableMetadata cfm, TupleType tupleType, List defs, VariableSpecifications boundNames) { SelectorFactories factories = createFactoriesAndCollectColumnDefinitions(selectables, tupleType.allTypes(), cfm, defs, boundNames); return TupleSelector.newFactory(tupleType, factories); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { // If there is only one element we cannot know if it is an element between parentheses or a tuple // with only one element. By consequence, we need to force the user to specify the type. if (selectables.size() == 1) return null; return Tuples.getExactTupleTypeIfKnown(selectables, p -> p.getExactTypeIfKnown(keyspace)); } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { // If there is only one element we cannot know if it is an element between parentheses or a tuple // with only one element. By consequence, we need to force the user to specify the type. if (selectables.size() == 1) return null; return Tuples.getExactTupleTypeIfKnown(selectables, p -> p.getCompatibleTypeIfKnown(keyspace)); } @Override public boolean selectColumns(Predicate predicate) { return Selectable.selectColumns(selectables, predicate); } @Override public String toString() { return Tuples.tupleToString(selectables); } public static class Raw implements Selectable.Raw { private final List raws; public Raw(List raws) { this.raws = raws; } @Override public Selectable prepare(TableMetadata cfm) { return new BetweenParenthesesOrWithTuple(raws.stream().map(p -> p.prepare(cfm)).collect(Collectors.toList())); } } } /** * Selectable for literal Lists. */ public static class WithArrayLiteral implements Selectable { /** * The list elements */ protected final List selectables; public WithArrayLiteral(List selectables) { this.selectables = selectables; } private Selectable target(AbstractType target) { // when the target isn't known, fallback to list; cases like "SELECT [1, 2]" can't be known, but used to be list type! // If a vector is actually desired, then can use type cast/hints: "SELECT (vector) [k, v1]" if (target == null || target instanceof ListType) return new WithList(selectables); else if (target.isVector()) return new WithVector(selectables); throw new IllegalArgumentException("Unsupported target type: " + target.asCQL3Type()); } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { return target(receiver == null ? null : receiver.type).testAssignment(keyspace, receiver); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { return target(expectedType).newSelectorFactory(cfm, expectedType, defs, boundNames); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { // TODO try to pass in a target to this API // default to list when type is being infered return new WithList(selectables).getExactTypeIfKnown(keyspace); } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { // TODO try to pass in a target to this API // default to list when type is being infered return new WithList(selectables).getCompatibleTypeIfKnown(keyspace); } @Override public boolean selectColumns(Predicate predicate) { return Selectable.selectColumns(selectables, predicate); } @Override public String toString() { return Lists.listToString(selectables); } public int getSize() { return selectables.size(); } public static class Raw implements Selectable.Raw { private final List raws; public Raw(List raws) { this.raws = raws; } @Override public Selectable prepare(TableMetadata cfm) { return new WithArrayLiteral(raws.stream().map(p -> p.prepare(cfm)).collect(Collectors.toList())); } } } public static class WithList extends WithArrayLiteral { public WithList(List selectables) { super(selectables); } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { return Lists.testListAssignment(receiver, selectables); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { AbstractType type = getExactTypeIfKnown(cfm.keyspace); if (type == null) { type = expectedType; if (type == null) throw invalidRequest("Cannot infer type for term %s in selection clause (try using a cast to force a type)", this); } ListType listType = (ListType) type; List> expectedTypes = new ArrayList<>(selectables.size()); for (int i = 0, m = selectables.size(); i < m; i++) expectedTypes.add(listType.getElementsType()); SelectorFactories factories = createFactoriesAndCollectColumnDefinitions(selectables, expectedTypes, cfm, defs, boundNames); return ListSelector.newFactory(type, factories); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { return Lists.getExactListTypeIfKnown(selectables, p -> p.getExactTypeIfKnown(keyspace)); } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { return Lists.getPreferredCompatibleType(selectables, p -> p.getCompatibleTypeIfKnown(keyspace)); } @Override public boolean selectColumns(Predicate predicate) { return Selectable.selectColumns(selectables, predicate); } @Override public String toString() { return Lists.listToString(selectables); } } public static class WithVector extends WithArrayLiteral { public WithVector(List selectables) { super(selectables); } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { return Vectors.testVectorAssignment(receiver, selectables); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { AbstractType type = getExactTypeIfKnown(cfm.keyspace); if (type == null) { type = expectedType; if (type == null) throw invalidRequest("Cannot infer type for term %s in selection clause (try using a cast to force a type)", this); } VectorType vectorType = (VectorType) type; if (vectorType.dimension != selectables.size()) throw invalidRequest("Unable to create a vector selector of type %s from %d elements", vectorType.asCQL3Type(), selectables.size()); List> expectedTypes = new ArrayList<>(selectables.size()); for (int i = 0, m = selectables.size(); i < m; i++) expectedTypes.add(vectorType.getElementsType()); SelectorFactories factories = createFactoriesAndCollectColumnDefinitions(selectables, expectedTypes, cfm, defs, boundNames); return VectorSelector.newFactory(type, factories); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { return Vectors.getExactVectorTypeIfKnown(selectables, p -> p.getExactTypeIfKnown(keyspace)); } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { return Vectors.getPreferredCompatibleType(selectables, p -> p.getCompatibleTypeIfKnown(keyspace)); } @Override public boolean selectColumns(Predicate predicate) { return Selectable.selectColumns(selectables, predicate); } @Override public String toString() { return Lists.listToString(selectables); } } /** * Selectable for literal Sets. */ public static class WithSet implements Selectable { /** * The set elements */ private final List selectables; public WithSet(List selectables) { this.selectables = selectables; } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { return Sets.testSetAssignment(receiver, selectables); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { AbstractType type = getExactTypeIfKnown(cfm.keyspace); if (type == null) { type = expectedType; if (type == null) throw invalidRequest("Cannot infer type for term %s in selection clause (try using a cast to force a type)", this); } // The parser treats empty Maps as Sets so if the type is a MapType we know that the Map is empty if (type instanceof MapType) return MapSelector.newFactory(type, Collections.emptyList()); SetType setType = (SetType) type; if (setType.getElementsType() == DurationType.instance) throw invalidRequest("Durations are not allowed inside sets: %s", setType.asCQL3Type()); List> expectedTypes = new ArrayList<>(selectables.size()); for (int i = 0, m = selectables.size(); i < m; i++) expectedTypes.add(setType.getElementsType()); SelectorFactories factories = createFactoriesAndCollectColumnDefinitions(selectables, expectedTypes, cfm, defs, boundNames); return SetSelector.newFactory(type, factories); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { return Sets.getExactSetTypeIfKnown(selectables, p -> p.getExactTypeIfKnown(keyspace)); } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { return Sets.getPreferredCompatibleType(selectables, p -> p.getCompatibleTypeIfKnown(keyspace)); } @Override public boolean selectColumns(Predicate predicate) { return Selectable.selectColumns(selectables, predicate); } @Override public String toString() { return Sets.setToString(selectables); } public static class Raw implements Selectable.Raw { private final List raws; public Raw(List raws) { this.raws = raws; } @Override public Selectable prepare(TableMetadata cfm) { return new WithSet(raws.stream().map(p -> p.prepare(cfm)).collect(Collectors.toList())); } } } /** * {@code Selectable} for literal Maps or UDTs. *

The parser cannot differentiate between a Map or a UDT in the selection cause because a * {@code ColumnIdentifier} is equivalent to a {@code FieldIdentifier} from a syntax point of view. * By consequence, we are forced to wait until the type is known to be able to differentiate them.

*/ public static class WithMapOrUdt implements Selectable { /** * The column family metadata. We need to store them to be able to build the proper data once the type has been * identified. */ private final TableMetadata cfm; /** * The Map or UDT raw elements. */ private final List> raws; public WithMapOrUdt(TableMetadata cfm, List> raws) { this.cfm = cfm; this.raws = raws; } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { return receiver.type.isUDT() ? UserTypes.testUserTypeAssignment(receiver, getUdtFields((UserType) receiver.type)) : Maps.testMapAssignment(receiver, getMapEntries(cfm)); } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { AbstractType type = getExactTypeIfKnown(cfm.keyspace); if (type == null) { type = expectedType; if (type == null) throw invalidRequest("Cannot infer type for term %s in selection clause (try using a cast to force a type)", this); } if (type.isUDT()) return newUdtSelectorFactory(cfm, expectedType, defs, boundNames); return newMapSelectorFactory(cfm, defs, boundNames, type); } private Factory newMapSelectorFactory(TableMetadata cfm, List defs, VariableSpecifications boundNames, AbstractType type) { MapType mapType = (MapType) type; if (mapType.getKeysType() == DurationType.instance) throw invalidRequest("Durations are not allowed as map keys: %s", mapType.asCQL3Type()); return MapSelector.newFactory(type, getMapEntries(cfm).stream() .map(p -> Pair.create(p.left.newSelectorFactory(cfm, mapType.getKeysType(), defs, boundNames), p.right.newSelectorFactory(cfm, mapType.getValuesType(), defs, boundNames))) .collect(Collectors.toList())); } private Factory newUdtSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { UserType ut = (UserType) expectedType; Map factories = new LinkedHashMap<>(ut.size()); for (Pair raw : raws) { if (!(raw.left instanceof RawIdentifier)) throw invalidRequest("%s is not a valid field identifier of type %s ", raw.left, ut.getNameAsString()); FieldIdentifier fieldName = ((RawIdentifier) raw.left).toFieldIdentifier(); int fieldPosition = ut.fieldPosition(fieldName); if (fieldPosition == -1) throw invalidRequest("Unknown field '%s' in value of user defined type %s", fieldName, ut.getNameAsString()); AbstractType fieldType = ut.fieldType(fieldPosition); factories.put(fieldName, raw.right.prepare(cfm).newSelectorFactory(cfm, fieldType, defs, boundNames)); } return UserTypeSelector.newFactory(expectedType, factories); } @Override public AbstractType getExactTypeIfKnown(String keyspace) { // Let's force the user to specify the type. return null; } @Override public AbstractType getCompatibleTypeIfKnown(String keyspace) { // Let's force the user to specify the type. return null; } @Override public boolean selectColumns(Predicate predicate) { for (Pair raw : raws) { if (!(raw.left instanceof RawIdentifier) && raw.left.prepare(cfm).selectColumns(predicate)) return true; if (!raw.right.prepare(cfm).selectColumns(predicate)) return true; } return false; } @Override public String toString() { return raws.stream() .map(p -> String.format("%s: %s", p.left instanceof RawIdentifier ? p.left : p.left.prepare(cfm), p.right.prepare(cfm))) .collect(Collectors.joining(", ", "{", "}")); } private List> getMapEntries(TableMetadata cfm) { return raws.stream() .map(p -> Pair.create(p.left.prepare(cfm), p.right.prepare(cfm))) .collect(Collectors.toList()); } private Map getUdtFields(UserType ut) { Map fields = new LinkedHashMap<>(ut.size()); for (Pair raw : raws) { if (!(raw.left instanceof RawIdentifier)) throw invalidRequest("%s is not a valid field identifier of type %s ", raw.left, ut.getNameAsString()); FieldIdentifier fieldName = ((RawIdentifier) raw.left).toFieldIdentifier(); int fieldPosition = ut.fieldPosition(fieldName); if (fieldPosition == -1) throw invalidRequest("Unknown field '%s' in value of user defined type %s", fieldName, ut.getNameAsString()); fields.put(fieldName, raw.right.prepare(cfm)); } return fields; } public static class Raw implements Selectable.Raw { private final List> raws; public Raw(List> raws) { this.raws = raws; } @Override public Selectable prepare(TableMetadata cfm) { return new WithMapOrUdt(cfm, raws); } } } /** * Selectable for type hints (e.g. (int) ?). */ public static class WithTypeHint implements Selectable { /** * The name of the type as specified in the query. */ private final String typeName; /** * The type specified by the hint. */ private final AbstractType type; /** * The selectable to which the hint should be applied. */ private final Selectable selectable; public WithTypeHint(String typeName, AbstractType type, Selectable selectable) { this.typeName = typeName; this.type = type; this.selectable = selectable; } @Override public TestResult testAssignment(String keyspace, ColumnSpecification receiver) { if (receiver.type.equals(type)) return AssignmentTestable.TestResult.EXACT_MATCH; else if (receiver.type.isValueCompatibleWith(type)) return AssignmentTestable.TestResult.WEAKLY_ASSIGNABLE; else return AssignmentTestable.TestResult.NOT_ASSIGNABLE; } @Override public Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { final ColumnSpecification receiver = new ColumnSpecification(cfm.keyspace, cfm.name, new ColumnIdentifier(toString(), true), type); if (!selectable.testAssignment(cfm.keyspace, receiver).isAssignable()) throw new InvalidRequestException(String.format("Cannot assign value %s to %s of type %s", this, receiver.name, receiver.type.asCQL3Type())); final Factory factory = selectable.newSelectorFactory(cfm, type, defs, boundNames); return new ForwardingFactory() { protected Factory delegate() { return factory; } protected AbstractType getReturnType() { return type; } protected String getColumnName() { return String.format("(%s)%s", typeName, factory.getColumnName()); } }; } @Override public AbstractType getExactTypeIfKnown(String keyspace) { return type; } @Override public boolean selectColumns(Predicate predicate) { return selectable.selectColumns(predicate); } @Override public String toString() { return String.format("(%s)%s", typeName, selectable); } public static class Raw implements Selectable.Raw { private final CQL3Type.Raw typeRaw; private final Selectable.Raw raw; public Raw( CQL3Type.Raw typeRaw, Selectable.Raw raw) { this.typeRaw = typeRaw; this.raw = raw; } public Selectable prepare(TableMetadata cfm) { Selectable selectable = raw.prepare(cfm); AbstractType type = this.typeRaw.prepare(cfm.keyspace).getType(); if (type.isFreezable()) type = type.freeze(); return new WithTypeHint(typeRaw.toString(), type, selectable); } } } /** * In the selection clause, the parser cannot differentiate between Maps and UDTs as a column identifier and field * identifier have the same syntax. By consequence, we need to wait until the type is known to create the proper * Object: {@code ColumnMetadata} or {@code FieldIdentifier}. */ public static final class RawIdentifier implements Selectable.Raw { private final String text; private final boolean quoted; /** * Creates a {@code RawIdentifier} from an unquoted identifier string. */ public static RawIdentifier forUnquoted(String text) { return new RawIdentifier(text, false); } /** * Creates a {@code RawIdentifier} from a quoted identifier string. */ public static RawIdentifier forQuoted(String text) { return new RawIdentifier(text, true); } private RawIdentifier(String text, boolean quoted) { this.text = text; this.quoted = quoted; } public ColumnMetadata columnMetadata(TableMetadata cfm) { return cfm.getExistingColumn(ColumnIdentifier.getInterned(text, quoted)); } @Override public Selectable prepare(TableMetadata cfm) { return columnMetadata(cfm); } public FieldIdentifier toFieldIdentifier() { return quoted ? FieldIdentifier.forQuoted(text) : FieldIdentifier.forUnquoted(text); } @Override public String toString() { return text; } } /** * Represents the selection of an element of a collection (eg. c[x]). */ public static class WithElementSelection implements Selectable { public final Selectable selected; // Note that we can't yet prepare the Term.Raw yet as we need the ColumnSpecificiation corresponding to Selectable, which // we'll only know in newSelectorFactory due to functions (which needs the defs passed to newSelectorFactory to resolve which // function is called). Note that this doesn't really matter performance wise since the factories are still created during // preparation of the corresponding SelectStatement. public final Term.Raw element; private WithElementSelection(Selectable selected, Term.Raw element) { assert element != null; this.selected = selected; this.element = element; } @Override public String toString() { return String.format("%s[%s]", selected, element); } public Selector.Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { Selector.Factory factory = selected.newSelectorFactory(cfm, null, defs, boundNames); ColumnSpecification receiver = factory.getColumnSpecification(cfm); AbstractType type = receiver.type; if (receiver.isReversedType()) { type = ((ReversedType) type).baseType; } if (!(type instanceof CollectionType)) throw new InvalidRequestException(String.format("Invalid element selection: %s is of type %s is not a collection", selected, type.asCQL3Type())); ColumnSpecification boundSpec = specForElementOrSlice(selected, receiver, ((CollectionType) type).kind, "Element"); Term elt = element.prepare(cfm.keyspace, boundSpec); elt.collectMarkerSpecification(boundNames); return ElementsSelector.newElementFactory(toString(), factory, (CollectionType)type, elt); } public AbstractType getExactTypeIfKnown(String keyspace) { AbstractType selectedType = selected.getExactTypeIfKnown(keyspace); if (selectedType == null || !(selectedType instanceof CollectionType)) return null; return ElementsSelector.valueType((CollectionType) selectedType); } @Override public boolean selectColumns(Predicate predicate) { return selected.selectColumns(predicate); } public static class Raw implements Selectable.Raw { private final Selectable.Raw selected; private final Term.Raw element; public Raw(Selectable.Raw selected, Term.Raw element) { this.selected = selected; this.element = element; } public WithElementSelection prepare(TableMetadata cfm) { return new WithElementSelection(selected.prepare(cfm), element); } @Override public String toString() { return String.format("%s[%s]", selected, element); } } } /** * Represents the selection of a slice of a collection (eg. c[x..y]). */ public static class WithSliceSelection implements Selectable { public final Selectable selected; // Note that we can't yet prepare the Term.Raw yet as we need the ColumnSpecificiation corresponding to Selectable, which // we'll only know in newSelectorFactory due to functions (which needs the defs passed to newSelectorFactory to resolve which // function is called). Note that this doesn't really matter performance wise since the factories are still created during // preparation of the corresponding SelectStatement. // Both from and to can be null if they haven't been provided public final Term.Raw from; public final Term.Raw to; private WithSliceSelection(Selectable selected, Term.Raw from, Term.Raw to) { this.selected = selected; this.from = from; this.to = to; } @Override public String toString() { return String.format("%s[%s..%s]", selected, from == null ? "" : from, to == null ? "" : to); } public Selector.Factory newSelectorFactory(TableMetadata cfm, AbstractType expectedType, List defs, VariableSpecifications boundNames) { // Note that a slice gives you the same type as the collection you applied it to, so we can pass expectedType for selected directly Selector.Factory factory = selected.newSelectorFactory(cfm, expectedType, defs, boundNames); ColumnSpecification receiver = factory.getColumnSpecification(cfm); AbstractType type = receiver.type; if (receiver.isReversedType()) { type = ((ReversedType) type).baseType; } if (!(type instanceof CollectionType)) throw new InvalidRequestException(String.format("Invalid slice selection: %s of type %s is not a collection", selected, type.asCQL3Type())); ColumnSpecification boundSpec = specForElementOrSlice(selected, receiver, ((CollectionType) type).kind, "Slice"); // If from or to are null, this means the user didn't provide on in the syntax (we had c[x..] or c[..x]). // The equivalent of doing this when preparing values would be to use UNSET. Term f = from == null ? Constants.UNSET_VALUE : from.prepare(cfm.keyspace, boundSpec); Term t = to == null ? Constants.UNSET_VALUE : to.prepare(cfm.keyspace, boundSpec); f.collectMarkerSpecification(boundNames); t.collectMarkerSpecification(boundNames); return ElementsSelector.newSliceFactory(toString(), factory, (CollectionType)type, f, t); } public AbstractType getExactTypeIfKnown(String keyspace) { AbstractType selectedType = selected.getExactTypeIfKnown(keyspace); if (selectedType == null || !(selectedType instanceof CollectionType)) return null; return selectedType; } @Override public boolean selectColumns(Predicate predicate) { return selected.selectColumns(predicate); } public static class Raw implements Selectable.Raw { private final Selectable.Raw selected; // Both from and to can be null if they haven't been provided private final Term.Raw from; private final Term.Raw to; public Raw(Selectable.Raw selected, Term.Raw from, Term.Raw to) { this.selected = selected; this.from = from; this.to = to; } public WithSliceSelection prepare(TableMetadata cfm) { return new WithSliceSelection(selected.prepare(cfm), from, to); } @Override public String toString() { return String.format("%s[%s..%s]", selected, from == null ? "" : from, to == null ? "" : to); } } } }




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