org.apache.calcite.rex

Class RexShuttle

java.lang.Object

org.apache.calcite.rex.RexShuttle

All Implemented Interfaces:

RexVisitor<RexNode>

Direct Known Subclasses:

ProjectCorrelateTransposeRule.RexFieldAccessReplacer, ReduceDecimalsRule.DecimalShuttle, ReduceExpressionsRule.CaseShuttle, ReduceExpressionsRule.RexReplacer, RelOptUtil.InputReferencedVisitor, RelOptUtil.RexInputConverter, RelOptUtil.VariableUsedVisitor, RexPermutationShuttle, RexPermuteInputsShuttle, RexUtil.ExprSimplifier, RexUtil.FixNullabilityShuttle

public class RexShuttle
extends Object
implements RexVisitor<RexNode>

Passes over a row-expression, calling a handler method for each node, appropriate to the type of the node.

Like RexVisitor, this is an instance of the Visitor Pattern. Use RexShuttle if you would like your methods to return a value.

Constructor Summary

Constructors

Constructor and Description
RexShuttle()

Method Summary

Modifier and Type	Method and Description
<T extends RexNode> @PolyNull List<T>	apply(@PolyNull List<T> exprList) Applies this shuttle to each expression in a list and returns the resulting list.
@PolyNull RexNode	apply(@PolyNull RexNode expr) Applies this shuttle to an expression, or returns null if the expression is null.
<T extends RexNode> boolean	mutate(List<T> exprList) Applies this shuttle to each expression in a list.
protected RexNode[]	visitArray(RexNode[] exprs, boolean[] update) Visits each of an array of expressions and returns an array of the results.
RexNode	visitCall(RexCall call)
RexNode	visitCorrelVariable(RexCorrelVariable variable)
RexNode	visitDynamicParam(RexDynamicParam dynamicParam)
RexNode	visitFieldAccess(RexFieldAccess fieldAccess)
protected List<RexFieldCollation>	visitFieldCollations(List<RexFieldCollation> collations, boolean[] update) Visits each of a list of field collations and returns a list of the results.
RexNode	visitInputRef(RexInputRef inputRef)
protected List<RexNode>	visitList(List<? extends RexNode> exprs, boolean[] update) Visits each of a list of expressions and returns a list of the results.
RexNode	visitLiteral(RexLiteral literal)
RexNode	visitLocalRef(RexLocalRef localRef)
RexNode	visitOver(RexOver over)
RexNode	visitPatternFieldRef(RexPatternFieldRef fieldRef)
RexNode	visitRangeRef(RexRangeRef rangeRef)
RexNode	visitSubQuery(RexSubQuery subQuery)
RexNode	visitTableInputRef(RexTableInputRef ref)
RexWindow	visitWindow(RexWindow window)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.calcite.rex.RexVisitor

visitEach, visitList, visitList

Constructor Detail

RexShuttle

public RexShuttle()

Method Detail

visitOver

public RexNode visitOver(RexOver over)

Specified by:

visitOver in interface RexVisitor<RexNode>

visitWindow

public RexWindow visitWindow(RexWindow window)

visitSubQuery

public RexNode visitSubQuery(RexSubQuery subQuery)

Specified by:

visitSubQuery in interface RexVisitor<RexNode>

visitTableInputRef

public RexNode visitTableInputRef(RexTableInputRef ref)

Specified by:

visitTableInputRef in interface RexVisitor<RexNode>

visitPatternFieldRef

public RexNode visitPatternFieldRef(RexPatternFieldRef fieldRef)

Specified by:

visitPatternFieldRef in interface RexVisitor<RexNode>

visitCall

public RexNode visitCall(RexCall call)

Specified by:

visitCall in interface RexVisitor<RexNode>

visitArray

protected RexNode[] visitArray(RexNode[] exprs,
                               boolean[] update)

Visits each of an array of expressions and returns an array of the results.

Parameters:

exprs - Array of expressions

update - If not null, sets this to true if any of the expressions was modified

Returns:

Array of visited expressions

visitList

protected List<RexNode> visitList(List<? extends RexNode> exprs,
                                  boolean[] update)

Visits each of a list of expressions and returns a list of the results.

Parameters:

exprs - List of expressions

update - If not null, sets this to true if any of the expressions was modified

Returns:

Array of visited expressions

visitFieldCollations

protected List<RexFieldCollation> visitFieldCollations(List<RexFieldCollation> collations,
                                                       boolean[] update)

Visits each of a list of field collations and returns a list of the results.

Parameters:

collations - List of field collations

update - If not null, sets this to true if any of the expressions was modified

Returns:

Array of visited field collations

visitCorrelVariable

public RexNode visitCorrelVariable(RexCorrelVariable variable)

Specified by:

visitCorrelVariable in interface RexVisitor<RexNode>

visitFieldAccess

public RexNode visitFieldAccess(RexFieldAccess fieldAccess)

Specified by:

visitFieldAccess in interface RexVisitor<RexNode>

visitInputRef

public RexNode visitInputRef(RexInputRef inputRef)

Specified by:

visitInputRef in interface RexVisitor<RexNode>

visitLocalRef

public RexNode visitLocalRef(RexLocalRef localRef)

Specified by:

visitLocalRef in interface RexVisitor<RexNode>

visitLiteral

public RexNode visitLiteral(RexLiteral literal)

Specified by:

visitLiteral in interface RexVisitor<RexNode>

visitDynamicParam

public RexNode visitDynamicParam(RexDynamicParam dynamicParam)

Specified by:

visitDynamicParam in interface RexVisitor<RexNode>

visitRangeRef

public RexNode visitRangeRef(RexRangeRef rangeRef)

Specified by:

visitRangeRef in interface RexVisitor<RexNode>

mutate

public final <T extends RexNode> boolean mutate(List<T> exprList)

Applies this shuttle to each expression in a list.

Returns:

whether any of the expressions changed

apply

public final <T extends RexNode> @PolyNull List<T> apply(@PolyNull List<T> exprList)

Applies this shuttle to each expression in a list and returns the resulting list. Does not modify the initial list.

Returns null if and only if exprList is null.

apply

public final @PolyNull RexNode apply(@PolyNull RexNode expr)

Applies this shuttle to an expression, or returns null if the expression is null.