Package org.apache.calcite.adapter.elasticsearch

Class PredicateAnalyzer.Visitor

java.lang.Object

org.apache.calcite.rex.RexVisitorImpl<PredicateAnalyzer.Expression>

org.apache.calcite.adapter.elasticsearch.PredicateAnalyzer.Visitor

All Implemented Interfaces:

RexVisitor<PredicateAnalyzer.Expression>

Enclosing class:

PredicateAnalyzer

private static class PredicateAnalyzer.Visitor
extends RexVisitorImpl<PredicateAnalyzer.Expression>

Traverses RexNode tree and builds ES query.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	PredicateAnalyzer.Visitor.SwapResult	Holder class for a pair of expressions.

Field Summary

Fields inherited from class org.apache.calcite.rex.RexVisitorImpl

deep

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Visitor()

Method Summary

Modifier and Type	Method	Description
private PredicateAnalyzer.QueryExpression	andOr(RexCall call)
private PredicateAnalyzer.QueryExpression	binary(RexCall call)	Process a call which is a binary operation, transforming into an equivalent query expression.
private static java.lang.String	convertQueryString(java.util.List<PredicateAnalyzer.Expression> fields, PredicateAnalyzer.Expression query)
private static PredicateAnalyzer.LiteralExpression	expressAsLiteral(PredicateAnalyzer.Expression exp)	Try to convert a generic expression into a literal expression.
private static boolean	isColumn(PredicateAnalyzer.Expression exp, RexNode node, java.lang.String columnName, boolean throwException)
private PredicateAnalyzer.QueryExpression	postfix(RexCall call)
private PredicateAnalyzer.QueryExpression	prefix(RexCall call)
private boolean	supportedRexCall(RexCall call)
private static PredicateAnalyzer.Visitor.SwapResult	swap(PredicateAnalyzer.Expression left, PredicateAnalyzer.Expression right)	Swap order of operands such that the literal expression is always on the right.
private PredicateAnalyzer.CastExpression	toCastExpression(RexCall call)
private static PredicateAnalyzer.NamedFieldExpression	toNamedField(RexLiteral literal)
PredicateAnalyzer.Expression	visitCall(RexCall call)
PredicateAnalyzer.Expression	visitInputRef(RexInputRef inputRef)
PredicateAnalyzer.Expression	visitLiteral(RexLiteral literal)

Methods inherited from class org.apache.calcite.rex.RexVisitorImpl

visitArrayAnd, visitArrayOr, visitCorrelVariable, visitDynamicParam, visitFieldAccess, visitLocalRef, visitOver, visitPatternFieldRef, visitRangeRef, visitSubQuery, visitTableInputRef

Methods inherited from class java.lang.Object

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

Constructor Detail

Visitor

private Visitor()

Method Detail

visitInputRef

public PredicateAnalyzer.Expression visitInputRef(RexInputRef inputRef)

Specified by:

visitInputRef in interface RexVisitor<PredicateAnalyzer.Expression>

Overrides:

visitInputRef in class RexVisitorImpl<PredicateAnalyzer.Expression>

visitLiteral

public PredicateAnalyzer.Expression visitLiteral(RexLiteral literal)

Specified by:

visitLiteral in interface RexVisitor<PredicateAnalyzer.Expression>

Overrides:

visitLiteral in class RexVisitorImpl<PredicateAnalyzer.Expression>

supportedRexCall

private boolean supportedRexCall(RexCall call)

visitCall

public PredicateAnalyzer.Expression visitCall(RexCall call)

Specified by:

visitCall in interface RexVisitor<PredicateAnalyzer.Expression>

Overrides:

visitCall in class RexVisitorImpl<PredicateAnalyzer.Expression>

convertQueryString

private static java.lang.String convertQueryString(java.util.List<PredicateAnalyzer.Expression> fields,
                                                   PredicateAnalyzer.Expression query)

prefix

private PredicateAnalyzer.QueryExpression prefix(RexCall call)

postfix

private PredicateAnalyzer.QueryExpression postfix(RexCall call)

binary

private PredicateAnalyzer.QueryExpression binary(RexCall call)

Process a call which is a binary operation, transforming into an equivalent query expression. Note that the incoming call may be either a simple binary expression, such as foo > 5, or it may be several simple expressions connected by AND or OR operators, such as foo > 5 AND bar = 'abc' AND 'rot' < 1

Parameters:

call - existing call

Returns:

evaluated expression

andOr

private PredicateAnalyzer.QueryExpression andOr(RexCall call)

swap

private static PredicateAnalyzer.Visitor.SwapResult swap(PredicateAnalyzer.Expression left,
                                                         PredicateAnalyzer.Expression right)

Swap order of operands such that the literal expression is always on the right.

NOTE: Some combinations of operands are implicitly not supported and will cause an exception to be thrown. For example, we currently do not support comparing a literal to another literal as convention 5 = 5. Nor do we support comparing named fields to other named fields as convention $0 = $1.

Parameters:

left - left expression

right - right expression

toCastExpression

private PredicateAnalyzer.CastExpression toCastExpression(RexCall call)

toNamedField

private static PredicateAnalyzer.NamedFieldExpression toNamedField(RexLiteral literal)

expressAsLiteral

private static PredicateAnalyzer.LiteralExpression expressAsLiteral(PredicateAnalyzer.Expression exp)

Try to convert a generic expression into a literal expression.

isColumn

private static boolean isColumn(PredicateAnalyzer.Expression exp,
                                RexNode node,
                                java.lang.String columnName,
                                boolean throwException)